https://wiki.batc.org.uk/api.php?action=feedcontributions&feedformat=atom&user=G8GKQBATC Wiki - User contributions [en-gb]2026-06-03T09:02:50ZUser contributionsMediaWiki 1.35.6https://wiki.batc.org.uk/index.php?title=SUP2400_mods&diff=12574SUP2400 mods2026-05-17T18:52:23Z<p>G8GKQ: </p>
<hr />
<div>In order to receive 437 MHz (70cms) DATV on a standard satellite STB or early MiniTiouners with Sharp or Eardtek tuners, you need to up convert the signal to L band. Current, version 2, MiniTiouners or PicoTuners using the Serit FTS-4334 (or FTS-4335) tuner cover from 144 MHz to 2450 MHz, so no up-conversion is required.<br />
<br />
For up-conversion (only required for standard Satellite STBs or very old version 1 MiniTiouners) there is a consumer device available in the USA which is used on cable networks to up convert UHF signals to L Band where they are then received on a standard satellite box. <br />
<br />
However, before use on 70cms, they either require hardware modification as described in CQ-TV 239 or the use of the Diseqc controller as described in CQ-TV 250.<br />
<br />
* [[SUP2400 DiSEqC| This page on the wiki describes the Disecq controller]]<br />
<br />
* [[:Media:Zinwell 70cms DATV up converter CQTV v2.pdf|Details of the hardware modifications are available here.]]</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=SUP2400_mods&diff=12573SUP2400 mods2026-05-17T18:51:58Z<p>G8GKQ: </p>
<hr />
<div>In order to receive 437 MHz (70cms) DATV on a standard satellite STB or early MiniTiouners with Sharp or Eardtek tuners, you need to up convert the signal to L band. Current, version 2, MiniTiouners or PicoTuners using the Serit FTS-4334 (or FTS-4335) tuner cover from 144 MHz to 2450 MHz, so no up-conversion is required.<br />
<br />
For up-conversion (only for standard Satellite STBs or very old version 1 MiniTiouners) there is a consumer device available in the USA which is used on cable networks to up convert UHF signals to L Band where they are then received on a standard satellite box. <br />
<br />
However, before use on 70cms, they either require hardware modification as described in CQ-TV 239 or the use of the Diseqc controller as described in CQ-TV 250.<br />
<br />
* [[SUP2400 DiSEqC| This page on the wiki describes the Disecq controller]]<br />
<br />
* [[:Media:Zinwell 70cms DATV up converter CQTV v2.pdf|Details of the hardware modifications are available here.]]</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12572The Muntjac SDR2026-05-14T19:52:25Z<p>G8GKQ: /* Problems */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
The flash chip has a capacity of 16M bytes, the maximum value for the RP2040 microcontroller. This gives plenty of room for software expansion and perhaps storing of transport streams to use as a beacon.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
Please put any comments, questions or problems on the BATC Muntjac forum: '''https://forum.batc.org.uk/viewforum.php?f=148'''<br />
<br />
'''The latest version of the Muntjac firmware is 1v0p. Please check your version on the Portsdown INFO screen.'''<br />
<br />
''' The ADE-30+ mixer is out of stock at DigiKey and low stock at Mouser, with lead times of August / September.'''<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br><br><br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for firmware version 1v0b. Later versions will blink 'MJ' and the last letter of the firmware version. After a few seconds for initialisation, the main LED will light steady.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square pad and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'. Adjust the frequency as required.<br />
<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
nc -kluv 9979<br />
<br />
The status is updated every second and should look something like this:<br />
<br />
======================================<br />
muntjacsdr_dvb-1v0m Portsdown driver version.<br />
muntjac4_pico-1v0p Muntjac firmware version.<br />
In: videots The driver transport stream input device.<br />
Out: /dev/ttyMJ0 The Muntjac device name.<br />
-------------------<br />
FR:2486.500 PWR:3 S:333 FEC:2/3 C:4 Main frequency and parameters.<br />
FR:780.000 PWR:26 Carrier This line appears when mixing.<br />
FT:146.500 The target frequency.<br />
-------------------------------------- <br />
Packets Frames Panic Nulls MJ Panic frames are inserted to prevent<br />
In Out Frames SR333 Errors the Muntjac from running out of data.<br />
-------------------------------------- Nulls SR333 are inserted to maintain <br />
4753 176 11 4 0 an output of 333333kS from an input of <br />
====================================== 333000.<br />
<br />
MJ0: [Muntjac4-1v0p:E46164855B404B30 (BUFFER_LOW:2046)]<br />
<br />
You may occasionally see a BUFFER_LOW message from the Muntjac. Some of the input modes <br />
are not completely constant bit rate in the short term, especially the testcard and <br />
contest numbers. A panic frame containing a few null packets is sent to the Muntjac to<br />
stop the receiver from losing lock.<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the serial number of the flash memory chip on the Muntjac. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. If you would like your calibration file added to this library, please e-mail it to G8GKQ. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected 26MHz TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Shoulders at Various Power Settings===<br />
<br />
The plots below show the effect of the power setting on the level of the shoulders at SR333. Shoulders are generally lower on 437MHz for the same power setting. <br> <br />
When using 8PSK, the requested power level is increased by 2, to maintain the same output power as for QPSK <br />
<br />
[[File:Snap80a.jpg|400px]] [[File:Snap76b.jpg|400px]]<br />
<br />
[[File:Snap75c.jpg|400px]] [[File:Snap77d.jpg|400px]]<br />
<br />
The rising levels at the edges of the plots are an artefact of the Pluto band viewer, as shown by the PWR8 plot in a 10MHz bandwidth.<br />
<br />
[[File:Snap78e.jpg|400px]]<br />
<br><br><br />
<br />
===Programming the Muntjac Microcontroller===<br />
<br />
Muntjacs are provided pre-programmed by the BATC Shop, but this is the procedure to load a firmware update if required. <br />
<br />
1. Download the latest compiled firmware in this zip file onto the PC desktop and unzip it: '''[[Media:muntjac4_pico-1v0p-uf2.zip|muntjac4_pico-1v0p-uf2.zip]]'''<br />
<br />
The unzipping program may put the wanted file '''muntjac4_pico-1v0p.uf2''' into a folder called '''muntjac4_pico-1v0p-uf2''' on the desktop.<br />
<br />
2. Hold down the BT button (the one nearer to the SMA sockets) on the Muntjac while connecting it to your PC using its USB port. <br />
<br><br />
or<br />
<br><br />
Plug the Muntjac into the PC and on the Muntjac, hold down the BT button while pressing and releasing the RS button. <br />
<br />
The main LED on the Muntjac will stay unlit when in firmware update mode.<br />
<br />
3. The Muntjac should now appear as a new drive connected to the PC. Your drive letter may be different. The drive name will be RPI-RP2 and there will be 2 files in it: INDEX.HTM and INFO_UF2.TXT<br />
<br />
[[File:Muntjac-virtual-drive2.png|800px]]<br />
<br />
Drag the '''muntjac4_pico-1v0p.uf2''' file that you unzipped in step 1 above (not the zip file itself, or the folder it was unzipped into), to the RPI-RP2 drive. The transfer should take about 5 seconds.<br />
<br />
The RPI-RP2 drive will then disappear and the Muntjac will restart itself.<br />
<br />
On the Muntjac, the main LED near the buttons will blink 'MJ' plus the last letter of the new firmware version. The LED will go out for a few seconds while the Muntjac is initialising and then light steady.<br />
<br />
The PC may bing-bong, as the Muntjac has now turned back into a COM port, but this can be ignored.<br />
<br />
4. Disconnect the Muntjac from the PC and connect it to the Portsdown. Wait until the main LED on the Muntjac is lit and steady.<br />
<br />
Make sure that "Output to" on the Portsdown main menu is set to "Muntjac". If this is the first time that this Muntjac has been connected to this Portsdown, while the Muntjac is connected to the Portsdown, change "Output to" to something other than "Muntjac" and then back to "Muntjac". The Portsdown will recognise a new Muntjac and the Portsdown will reboot itself as part of the Muntjac registration process.<br />
<br />
When the Portsdown has rebooted and the main LED on the Muntjac is lit and steady, on the Portsdown select "M2" and "Info" and the Muntjac firmware version and serial number will be displayed as shown below.<br />
<br />
[[File:Portsdown-info-screen2.png|800px]]<br />
<br><br><br />
<br />
===Alternative Method of Putting the Microcontroller into Firmware Update Mode===<br />
<br />
This may be useful if you've built the Muntjac into a box and cannot easily get to its buttons. <br />
<br />
1. Plug the Muntjac into a PC and it will appear as a COM port. Note that this may not work through a USB3 hub.<br />
<br />
2. Find the COM port number in device manager and open a serial terminal session to that COM port at 1200 baud, with a terminal program such as putty.<br />
<br />
3. The COM port will instantly disappear and the Muntjac will then appear as a USB drive.<br />
<br />
4. Proceed with step 3 in the section above.<br />
<br />
Note that this depends on the firmware already in the Muntjac being configured to do this by the SDK (software development kit). This approach would not work on a blank Raspberry Pi Pico board, which uses the same RP2040 microcontroller as the Muntjac.<br />
<br />
[[File:MJputty1.png|400px]]<br />
<br />
<br />
===Updating the Muntjac Firmware Using a Portsdown===<br />
<br />
If the Muntjac is built into a Portsdown system, it may not be possible to access its USB socket. A procedure is being developed to help with this.<br />
<br />
===Mixing Options===<br />
<br />
As both high and low band outputs may be active at the same time, this gives some options for using a mixer to transvert to other bands.<br />
<br />
The same DATV transmission can be made simultaneously on both bands (but NOT from a Portsdown menu), but either band can output a carrier instead and the third harmonic of the low band output can be used to mix the high band output to various frequencies.<br />
<br />
These notes are to guide experimentation. Some of the high band frequencies are outside the published specification of the AT86RF215 chip (2400-2483.5MHz). The output must be monitored for quality, stability and frequency accuracy. <br />
<br />
Any mixer output MUST be bandpass filtered for the required output frequency. This is particularly important for 23cm, where on 1270MHz for example, the required third harmonic of the low band carrier may be only 58MHz away from the target frequency.<br />
<br />
The low band carrier power is set at 26, which is nominally +11dBm. If a passive mixer is used, a Level7 (7dBm local oscillator) mixer is recommended. A suitable mixer is a MiniCircuits ADE-30+ (NOT the ADE-30W+, although that may be more suitable depending on your requirements). Mixers in the ADE series can look the same, but have different footprints, so do check carefully that any other mixer is compartible with the pcb. https://www.minicircuits.com/pdfs/ADE-30+.pdf<br />
<br />
The high and low band outputs are connected to the RF and LO ports of the mixer, which are specced at 200-3000MHz and the output is taken from the IF port, which is specced at 0-1000MHz. The output is likely to be in the range of the tens of microwatts. The 23cm band is outside the IF range, but still produces a usable output. <br />
<br />
The following frequency ranges are built into the Muntjac driver in the Portsdown. Putting the target frequency into Portsdown will automatically select the correct high and low band frequencies for mixing. <br />
<br />
{| class="wikitable"<br />
|+ Mixing Options<br />
|-<br />
! Target !! Low !! Harmonic !! High<br />
|-<br />
| 3400-3410 || 1010 || - || 2390-2400<br />
|-<br />
| 1300-1305 || 395 || 1185 || 2395-2400<br />
|-<br />
| 1270-1280 || 404 || 1212 || 2482-2492<br />
|-<br />
| 1244-1250 || 390 || 1170 || 2414-2420<br />
|-<br />
| 144-147 || 780 || 2340 || 2484-2487<br />
|-<br />
| 70.5-71.5 || 805 || 2415 || 2485.5-2486.5<br />
|-<br />
| 50-54 || 812 || 2436 || 2486-2490<br />
|-<br />
| 28-30 || 819 || 2457 || 2483-2485<br />
|}<br />
<br />
<br><br />
<br />
===Fitting and Connecting the Onboard Mixer===<br />
<br />
[[File:Mjmixer1a.png|400px|thumb|left]]<br />
<br />
Fit the MX101 mixer here, with its pin 1 dot marker close to the thick bar at the south-east of the pcb legend. <br />
<br />
An ADE-30+ has been used for testing. Other mixers may look the same, but may have different pinouts.<br />
<br />
The mixer inputs are connected to the high and low band outputs of the AT86RF215 by bridging the pairs of rectangular pads shown in the red circles. There is no way to disconnect the SMA outputs.<br />
<br />
The green arrow shows the C101 mixer output capacitor, which if factory fitted, will be 100pF 0603. This may be too low, depending on where you're mixing to.<br />
<br />
The blue arrow shows the round pad for the centre of an output coax lead. Use the nearby SMA ground pin for the outer.<br />
<br />
<br style="clear: both" /><br />
<br />
===Using the Third Harmonic of the Low Band for DATV on 23cm===<br />
<br />
The third harmonic of 418.333 MHz can be used to transmit on 1255 MHz. The third harmonic is about 20 dB down on the fundamental, so good filtering is required. More details will appear here.<br />
<br />
[[File:Third Harmonic.jpg|400px]]<br />
<br />
''The fundamental at 418.3 MHz on the left with the 3rd harmonic on 1255 MHz on the right''<br />
<br />
===Command Line Operation===<br />
<br />
This gives full control over frequency and power on both high and low band simultaneously and enables Portsdown band viewer to be run at the same time.<br />
<br />
Details will appear here.<br />
<br />
===Muntjac Schematic===<br />
<br />
Downloadable PDF files will be available shortly.<br />
<br />
[[File:Image 2026-04-28 12-58-03.png|1080px]]<br />
<br />
<br />
===Muntjac Input/Output Connectors===<br />
<br />
The 40 pin J101 position will enable the Muntjac to connect directly to a Raspberry Pi. This will provide power and also an SPI connection instead of USB, allowing higher data rates for future development. It is recommended that no connector is fitted here until the required orientation and gender is known.<br />
<br />
The 8 pin J3 position can be used for general I/O or to allow future developments to connect a WIZnet Ethernet module for applications that do not require a Raspberry Pi.<br />
<br />
The 12 pin J4 position is for general I/O. <br />
<br />
3.3v power is available on J3 and J4. The available current is yet to be determined, but likely to be around 100mA.<br />
<br />
All Muntjac I/O pins on J3 and J4 are connected directly to the RP2040 microcontroller, so caution should be exercised regarding static and voltage levels. 3.3v is the nominal voltage level.<br />
<br />
There are no pins on J3 or J4 that connect to J101.<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a some USB hubs. The USB3 sockets on the RPi4 are not a problem. However, it will appear as a virtual USB drive for firmware update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
===Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Repeater_Controller_configuration&diff=12570Repeater Controller configuration2026-05-11T19:24:47Z<p>G8GKQ: /* TX key and Power Saving logic - also in SSH menu (see above for description) */</p>
<hr />
<div> Back to [[Repeater Controller|repeater controller]] main page<br />
<br />
This page describes the setup of the BATC repeater controller - it should only be attempted by advanced users.<br />
<br />
'''Note not all functions listed in the config file are currently implemented.<br />
'''<br />
=SSH Menu=<br />
<br />
Some configuration and some real-time control is possible using the ssh Console Menu.<br />
<br />
To enter the repeater controller menu log in to the RPi by SSH using a program such as Putty and type menu.<br />
<br />
[[File:controller main.JPG|600px]]<br />
<br />
===Reload=== <br />
<br />
Loads the configuration changes you have made and restarts the controller<br />
<br />
===1 Behaviour===<br />
<br />
1 - Audio keepalive. Some HDMI switches permanently shut down the audio channel is no audio is present. This option puts low-level white noise on the controller audio out to prevent this from happening.<br />
<br />
2 - Transmit enable. Enables transmit key line on pin xx<br />
<br />
3 - Beacon mode. Enables the controller to just run in beacon mode and ignore all inputs.<br />
<br />
4 - Power save. Enables transmit key line to be on continuously or just when the controller sees a valid input signal or when sending an ident.<br />
<br />
5 - Operating hours. Selection of transmit key line to be active continuously or just during a timed period to save power. If timed, select the start and stop times. Note time is set using UTC time, not local time.<br />
<br />
6 - Quiet hours repeat. If Timed operation was selected in menu 5, you can set if the repeater should repeat an input signal during the quiet time.<br />
<br />
7 - Quiet hours ident. If Timed operation was selected in menu 5, you can set if the repeater should send the ident signal during the quiet time.<br />
<br />
8 - Half hour. If enabled, the transmitter will only be keyed in beacon mode during the first 30 minutes of every hour and not during the 2nd half hour to save power.<br />
<br />
9 - Quad auto enable. Enables the quad display to be automatically displayed when more than 1 selected inputs are present.<br />
<br />
10 - Enable DTMF input. Enables over air DTMF control of the repeater<br />
<br />
11 - Apply changes<br />
<br />
12 - Return to main menu<br />
<br />
===2 Callsign===<br />
<br />
Entry of the repeater callsign and QRA locator for display on generated captions.<br />
<br />
===3 Inputs===<br />
<br />
1 - 7 Input. Enables priority of each input to be set<br />
<br />
8 - Input count. Set this to the total number of inputs on the video switcher - Do NOT include the controller in this number.<br />
<br />
9 - Active Hold. Determines if a higher priority input will override the currently selected input.<br />
<br />
10 - Apply<br />
<br />
11 - Main Menu<br />
<br />
===4 Control===<br />
<br />
Enables direct selection of any input source<br />
<br />
===5 Update===<br />
Check s/w version and update if needed.<br />
<br />
===6 Settings===<br />
<br />
1 - Reset factory defaults<br />
<br />
2 - Check HDMI. Lists the HDMI settings for fault finding<br />
<br />
3 - Main menu.<br />
<br />
===7 Diagnostics===<br />
<br />
===8 Reboot===<br />
<br />
Does exactly that!<br />
<br />
=Controlling the Repeater During Testing=<br />
<br />
===Stopping the Controller===<br />
<br />
The controller can be stopped by entering<br />
stop<br />
at the command line. This tells all the repeater processes to stop and should show a "Controller Software Not Running" caption on the HDMI output.<br />
<br />
===Restarting the Controller for Testing===<br />
<br />
You can restart the controller for testing by entering<br />
rptr<br />
You will see a running commentary of what the repeater is doing in the console window. However, if you close the window, the repeater will stop. You can also stop it and get back to the command prompt by pressing ctrl-c.<br />
<br />
You can start the repeater so that it runs and keeps a log of what it is doing (even if you close the controller window) by entering this command:<br />
nohup atv-rptr/utils/run_rptr_nohup_with_log.sh &<br />
Then press ctrl-c to get back to the command prompt.<br />
<br />
If you see behaviour that you want to investigate, enter<br />
stop<br />
to force the last bit of the log to be written to the file, and then enter<br />
tail -25 log.txt<br />
to see the last 25 lines of the log.<br />
<br />
Do not run the repeater for normal use using these test modes. The log file will grow over time and eventually fill the SD Card, causing the repeater to fail.<br />
<br />
===Getting Back to Normal Use===<br />
<br />
At the end of a maintenance session, you should always reboot the repeater to check that it is working properly and put it in its normal mode. Do this by typing<br />
sudo reboot now<br />
Close the SSH window, watch the repeater output and if all is well, walk away.<br />
<br />
===Advanced Commands===<br />
<br />
If you need to edit the C code, you can recompile it and run the repeater software with the command<br />
urptr<br />
This will also show you any errors if the compilation fails.<br />
<br />
If you need to troubleshoot the output display settings, use<br />
tvservice -s<br />
<br />
=Editing the config file=<br />
<br />
The configuration file is too comprehensive for all the functions to be edited from a simple menu and more advanced customisation will require the careful editing of the text file /home/pi/atv-rptr/config/repeater_config.txt<br />
<br />
===Hand edit===<br />
You can hand-edit the configuration file with the command<br />
nano atv-rptr/config/repeater_config.txt<br />
Use the arrow keys to move about (not the mouse) and save by pressing ctrl-x, y and then enter. Discard changes by simply pressing ctrl-x and then n.<br />
<br />
If it has all gone wrong, you can start again with a factory-fresh configuration file using the command<br />
cp atv-rptr/config/repeater_config.txt atv-rptr/config/repeater_config.txt.factory<br />
Note that you will lose all of your previous edits.<br />
<br />
===FTP===<br />
<br />
Use a program such as WinSCP or Filezilla and either edit the config file in the RPi directory or copy it to a local drive, edit and then transfer it back.<br />
<br />
==Actioning the changes==<br />
<br />
After editing and saving, reload the controller by using item 1 in the SSH menu.<br />
<br />
=IR Commands=<br />
<br />
Where IR Commands are used in the config file, they are in the format<br />
=protocol:code<br />
for example:<br />
outputhdmiquadcode=nec:0x18<br />
<br />
As of software update 202503030, multiple IR commands can be sent for one function by the use of commas:<br />
outputhdmiquadcode=nec:0x18,nec0x18,nec0x18<br />
This command would send code 0x18 three times with an interval of 200ms in between. Commas are only permissible in the middle of the message, not at the start or end. No spaces allowed. Max length 63 characters.<br />
<br />
=Typical config file=<br />
<br />
The following is an example of a typical config with comments on each function - some functions are also available in the SSH menu<br />
<br />
===Introduction===<br />
Text file defining behaviour and config of the BATC HDMI Repeater Design<br />
Comments must be on their own line<br />
Read at boot time and only modified from console menu or text editor except transmitenabled which is amended by dtmfkeepertxoff or dtmfkeepertxon<br />
<br />
===Station Details - also in SSH menu===<br />
callsign=GB3HV<br />
<br />
locator=IO91LD<br />
<br />
===Video output===<br />
Used to size captions and layout display only. It does NOT set the output to hdmi720, hdmi1080, pal, ntsc <br />
vidout=hdmi1080<br />
<br />
===Ident and K CW audio output===<br />
This is used to set the output port (but not the hdmi keep-alive)<br />
hdmi, jack or usb<br />
<br />
audioout=hdmi<br />
<br />
===Low level audio - also in SSH menu===<br />
Turn on low level audio noise to keep hdmi audio active? yes/no<br />
audiokeepalive=yes<br />
<br />
audiokeepalivelevel=85<br />
<br />
===TX key and Power Saving logic - also in SSH menu (see above for description)===<br />
Enable/disable transmit ptt active? yes/no<br />
transmitenabled=yes<br />
<br />
Beacon mode only transmits carousel with ident. Set to no for rptr operation. yes/no<br />
beaconmode=no<br />
<br />
Continuous TX or power-saving. no/yes<br />
transmitwhennotinuse=yes<br />
<br />
Only transmit when input active. no/yes<br />
minimisetx=no<br />
<br />
Control mains switch for rack (and allocate GPIOs?). Note not compatible with use of input 7<br />
rackmainscontrol=yes<br />
<br />
GPIO pins for controlled rack shutdown (front panel button, shutdown signal and mains switch<br />
racksdbuttongpiopin=21<br />
racksdsignalgpiopin=24<br />
rackmainspwrgpiopin=15<br />
<br />
Turn off receiver rack and encoder to save power? Times UTC<br />
rackpowersave=yes<br />
rackpoweron1=1500<br />
rackpoweroff1=2300<br />
Set second times to be equal for one power-on period only<br />
rackpoweron2=0000<br />
rackpoweroff2=0000<br />
<br />
Continuous operation or active hours only. yes/no<br />
24houroperation=yes<br />
<br />
Power save during second half hour in active hours? Default no.<br />
Repeat and Ident are available/active during this time<br />
halfhourpowersave=no<br />
<br />
Operating times are UTC. Ignored for 24/7 operation<br />
operatingtimestart=1300<br />
<br />
operatingtimefinish=2330<br />
<br />
Quiet hours behaviour:<br />
repeatduringquiethours=no<br />
<br />
identduringquiethours=no<br />
<br />
===Transmit PTT Demand physical pin===<br />
Recommended pin 40<br />
pttgpiopin=40<br />
<br />
===Front Panel Shutdown Enabled?===<br />
Physical GPIO Pin (recommended 26)<br />
<br />
fpshutdown=no<br />
<br />
fpsdgpiopin=26<br />
<br />
===DTMF repeater control===<br />
<br />
Uses white "Portsdown/Langstone" USB dongle input<br />
<br />
These are just example commands - see [[DATV repeater DTMF commands]] for more details<br />
<br />
Control is on/off. Gain is %. Timeout is in seconds<br />
<br />
dtmfcontrol=on<br />
<br />
dtmfaudiogain=62<br />
<br />
dtmfactiontimeout=600<br />
<br />
<br />
'''All dtmf codes are of the format *xx#.''' Only xx isdefined below. Examples:<br />
<br />
dtmfreset=00<br />
<br />
To display the controller status screen - includes GPIO pin status (see below)<br />
<br />
dtmfstatusview=01<br />
<br />
Select quad view<br />
<br />
dtmfquadview=04<br />
<br />
Select input (when finished, use *00# to return to normal operation)<br />
<br />
dtmfselectinput0=10<br />
<br />
dtmfselectinput1=11<br />
<br />
dtmfselectinput2=12<br />
<br />
dtmfselectinput3=13<br />
<br />
dtmfselectinput4=14<br />
<br />
dtmfselectinput5=15<br />
<br />
dtmfselectinput6=16<br />
<br />
dtmfselectinput7=17<br />
<br />
===DTMF Keeper codes===<br />
'''In this example''' keeper codes are 5 digit and must start with 9 (*9xxxx#)<br />
<br />
Turns Tx key on / off<br />
<br />
dtmfkeepertxoff=97350<br />
<br />
dtmfkeepertxon=97351<br />
<br />
Reboot controller<br />
<br />
dtmfkeeperreboot=97359<br />
<br />
===DTMF Accessory Control examples===<br />
DTMF input can also be used to control external equipment via the GPIO pins - a maximum of 10 devices can be connected.<br />
<br />
Number of outputs<br />
<br />
dtmfoutputs=1<br />
<br />
Pin allocations<br />
<br />
dtmfgpioout1pin=8<br />
<br />
Label for status screen<br />
<br />
dtmfgpioout1label=shack_light<br />
<br />
DTMF commands to turn on and off<br />
<br />
dtmfgpioout1on=31<br />
<br />
dtmfgpioout1off=41<br />
<br />
===GPIO inputs===<br />
The controller can monitor GPIO pins and display their status on the status screen, displayed by DTMF *01# Note: Due to an error in coding, these functions are called "dtmf"gpio inputs.<br />
<br />
Number of inputs<br />
<br />
dtmfinputs=1<br />
<br />
Pin allocationa<br />
<br />
dtmfgpioin1pin=8<br />
<br />
Label for status screen<br />
dtmfgpioin1label=cabinet_door<br />
<br />
===Background image for Caption Slides===<br />
Caption cards such as "K" and input identification are built by the controller on this back ground - to change this, replace the .jpg with a different file of the same resolution<br />
<br />
backimage=/home/pi/atv-rptr/media/batc_background.jpg<br />
<br />
===Ident info===<br />
<br />
Audio is on/off, Pitch in Hz, speed in wpm, level is %<br />
<br />
identinterval=900<br />
<br />
identmediatype=jpg<br />
<br />
identmediaduration=5<br />
<br />
identmediafile=/home/pi/tmp/ident.jpg<br />
<br />
identcwaudio=on<br />
<br />
identcwspeed=15<br />
<br />
identcwpitch=800<br />
<br />
identcwlevel=50<br />
<br />
identcwfile=/home/pi/tmp/ident.wav<br />
<br />
===K information===<br />
Pitch in Hz, speed in wpm, level is %<br />
kmediatype=jpg<br />
<br />
kmediaduration=5<br />
<br />
kmediafile=/home/pi/tmp/k.jpg<br />
<br />
kcwaudio=on<br />
<br />
kcwspeed=20<br />
<br />
kcwpitch=800<br />
<br />
kcwlevel=50<br />
<br />
kcwfile=/home/pi/tmp/k.wav<br />
<br />
===Carousel information=== <br />
The carousel can have up to 99 scenes. Each scene can either be jpg, (mp4 not implemented in current release), status screen or a video source on the switcher. Jpeg images are read each time the file is displayed. For a video source, "file" is source number which can be an individual source or the multi grid, if supported by the video switch.<br />
<br />
carouselscenes=5<br />
<br />
carousel01mediatype=jpg<br />
carousel01file=/home/pi/atv-rptr/media/HVtest.jpg<br />
carousel01mediaduration=10<br />
<br />
carousel02mediatype=jpg<br />
carousel02file=/home/pi/atv-rptr/media/weather.JPG<br />
carousel02mediaduration=10<br />
<br />
carousel03mediatype=jpg<br />
carousel03file=/home/pi/atv-rptr/media/75cbw.jpg<br />
carousel03mediaduration=5<br />
<br />
carousel04mediatype=jpg<br />
carousel04file=/home/pi/custom_media/tropo.JPG<br />
carousel04mediaduration=10<br />
<br />
carousel05mediatype=source<br />
carousel05file=4<br />
carousel05mediaduration=30<br />
The example above has 4 images and one source (so 5 scenes). The 5th scene is the quad view; source 4 is set up below to show the Quad to enable its inclusion in the carousel. <br />
<br />
Note that the 4th image above is located in the /home/pi/custom_media folder. It is recommended that site-specific images are saved in that folder, which will not be over-written during software updates.<br />
<br />
===Analogue Talkback Audio on Carousel===<br />
<br />
If using an i2c analogue audio switcher, the talkback audio can be enabled during the carousel<br />
<br />
# Analogue talkback audio (144.75) can be turned on or off using the MCP23008 i2c switcher<br />
talkbackaudio=on<br />
talkbackaudioi2cbit=7<br />
<br />
If using hdmi audio, the talkback can be input on the USB mic dongle (along with the DTMF) and output on the HDMI audio during the carousel. The audio gain is set by the dtmfaudiogain parameter as they both use the same input. Facility introduced in release 202402190.<br />
<br />
# Talkback audio on DTMF input can also be output on the controller (k/cw ident) audio channel<br />
# Volume is set by dtmfaudiogain above<br />
controllertalkbackaudio=on<br />
<br />
===Input configuration===<br />
<br />
Recommended gpio pins for "input active" are 32, 35, 18, 22, 16, 19 and 21. The availableinputs number must be set to the number of possibly active (external, in addition to the controller) video sources. activeinputhold (yes/no) means that lower priority inputs do not get replaced by higher priority active inputs (except priority 1 inputs). If showquadformultipleinputs is set to yes, then the quad is sleected when 2 or more if its inputs are active.<br />
<br />
Cascaded switches refers to whether 2 4-input switches are daisy chaned t get 7 (controller plus 6 external) inputs.<br />
<br />
availableinputs=6<br />
activeinputhold=no<br />
showquadformultipleinputs=yes<br />
cascadedswitches=no<br />
<br />
===Output video switch config===<br />
<br />
The output video switch configuration is defined by this block. The switching method is defined by outputswitchcontrol=. This can be ir, gpio or html. For ir or html, the gpio outputs can also be active if showoutputongpio= is set to yes.<br />
<br />
The ir code to reset the hdmi switch (not currently used) is set in outputhdmiresetcode. The ir code to select a second (daisy-chained) hdmi switch is set in output2ndhdmicode. The ir code to select a quad view is set in outputhdmiquadcode.<br />
<br />
The outputi2caddress is the base address for an i2c video switch, and the outputi2cquadchannel is the quad select for an i2c video switch. Neither of these codes are currently implemented.<br />
<br />
outputswitchcontrol=ir<br />
showoutputongpio=yes<br />
outputhdmiresetcode=nec:0x17<br />
output2ndhdmicode=nec:0x17<br />
outputhdmiquadcode=nec:0x18<br />
outputi2caddress=3<br />
outputi2cquadchannel=9<br />
<br />
===Bitfocus Companion Server Settings===<br />
<br />
# Bitfocus Companion (html) server address & port (no trailing slash)<br />
networkctrlurl=http://192.0.1.176:8888<br />
# Other net commands have leading slash<br />
outputquadnetcommand=/press/bank/1/11<br />
<br />
===Configure input 0 - always allocated to controller===<br />
<br />
The configuration for the controller output 6 elements (currently).<br />
<br />
The input0name is the text name displayed on the Configuration screen.<br />
<br />
The IR code required to select the controller video and send it to the repeater output is stated in output0code. The format is protocol:hex code. A 2 is added to the beginning of the string if the the input is on the second, daisy-chained, hdmi switch (ie 2nec:0x17). If GPIO switching of outputs is used, the output0hdmiswitchpin indicates which pin should be used. If an i2c-controlled video switcher is used, output0i2cchannel indicates which channel should be selected to display that input. Similarly, if network commands are being used to control an ATEM switch through BitFocus companion, the tail end of the network command is defined by output0netcommand.<br />
<br />
For audio i2c switching, the correct bit is set by output0audioi2cbit.<br />
<br />
input0name=Controller<br />
output0code=nec:0x17<br />
#output0code=2nec:0x17 (daisy chain)<br />
output0hdmiswitchpin=36<br />
output0i2cchannel=1<br />
output0netcommand=/press/bank/1/8<br />
output0audioi2cbit=0<br />
<br />
===Configuration of External Inputs===<br />
<br />
The configuration for each input has 11 elements (currently).<br />
<br />
The inputxname is the text name displayed on the "announce" caption and on the Configuration screen. The priority level can be set from 1 to 9. A priority level of 9 means that the input is not displayed unless it is viewed as part of the quad or is directly selected by a DTMF command.<br />
<br />
The inputxactivegpiopin is the physical pin number that the attached receiver sets high to indicate that a signal is present. The IR code required to select the input and send it to the repeater output is stated in outputxcode. The format is protocol:hex code. A 2 is added to the beginning of the string if the the input is on the second, daisy-chained, hdmi switch (ie 2nec:0x12). If GPIO switching of outputs is used, the outputxhdmiswitchpin indicates which pin should be used. If an i2c-controlled video switcher is used, outputxi2cchannel indicates which channel should be selected to display that input. Similarly, if network commands are being used to control an ATEM switch through BitFocus companion, the tail end of the network command is defined by outputxnetcommand.<br />
<br />
For audio i2c switching, the correct bit is set by outputxaudioi2cbit.<br />
<br />
The default announce media settings work with the captions that are generated during repeater start-up. The can be cahnge for custom media if required.<br />
<br />
===Configure input 1===<br />
<br />
input1name=Stream Input<br />
input1prioritylevel=1<br />
input1activegpiopin=32<br />
output1code=nec:0x12<br />
output1hdmiswitchpin=37<br />
output1i2cchannel=2<br />
output1netcommand=/press/bank/1/1<br />
output1audioi2cbit=1<br />
input1announcemediatype=jpg<br />
input1announcemediafile=/home/pi/tmp/input1.jpg<br />
input1announcemediaduration=3<br />
<br />
===Configure input 2===<br />
<br />
input2name=QO-100 RX<br />
input2prioritylevel=2<br />
input2activegpiopin=35<br />
output2code=nec:0x59<br />
output2hdmiswitchpin=38<br />
output2i2cchannel=3<br />
output2netcommand=/press/bank/1/2<br />
output2audioi2cbit=2<br />
input2announcemediatype=jpg<br />
input2announcemediafile=/home/pi/tmp/input2.jpg<br />
input2announcemediaduration=3<br />
<br />
===Configure input 3===<br />
<br />
input3name=3.4 GHz Ryde<br />
input3prioritylevel=3<br />
input3activegpiopin=18<br />
output3code=nec:0x08<br />
output3hdmiswitchpin=33<br />
output3i2cchannel=4<br />
output3netcommand=/press/bank/1/3<br />
output3audioi2cbit=3<br />
input3announcemediatype=jpg<br />
input3announcemediafile=/home/pi/tmp/input3.jpg<br />
input3announcemediaduration=3<br />
<br />
===Configure input 4===<br />
Input 4 is set to display the quad view. This enables it to be included in the carousel (as source 4).<br />
<br />
input4name=Quad View<br />
input4prioritylevel=7<br />
input4activegpiopin=22<br />
output4code=nec:0x18<br />
#output4code=2nec:0x12 (daisy chain, not quad)<br />
output4hdmiswitchpin=31<br />
output4i2cchannel=5<br />
output4netcommand=/press/bank/1/4<br />
output4audioi2cbit=4<br />
input4announcemediatype=jpg<br />
input4announcemediafile=/home/pi/tmp/input4.jpg<br />
input4announcemediaduration=3<br />
<br />
===Configure input 5===<br />
<br />
input5name=Mast Camera<br />
input5prioritylevel=7<br />
input5activegpiopin=16<br />
output5code=2nec:0x59<br />
output5hdmiswitchpin=29<br />
output5i2cchannel=6<br />
output5netcommand=/press/bank/1/5<br />
output5audioi2cbit=5<br />
input5announcemediatype=jpg<br />
input5announcemediafile=/home/pi/tmp/input5.jpg<br />
input5announcemediaduration=10<br />
<br />
===Configure input 6===<br />
<br />
input6name=Unused 6<br />
input6prioritylevel=9<br />
input6activegpiopin=19<br />
output6code=2nec:0x08<br />
#output6code=2nec:0x08 (daisy chain)<br />
output6hdmiswitchpin=23<br />
output6i2cchannel=7<br />
output6netcommand=/press/bank/1/6<br />
output6audioi2cbit=6<br />
input6announcemediatype=jpg<br />
input6announcemediafile=/home/pi/tmp/input6.jpg<br />
input6announcemediaduration=3<br />
<br />
===Configure input 7===<br />
<br />
input7name=Unused 7<br />
input7prioritylevel=9<br />
input7activegpiopin=21<br />
output7code=2nec:0x08<br />
#output7code=2nec:0x12 (daisy chain)<br />
output7hdmiswitchpin=24<br />
output7i2cchannel=8<br />
output7netcommand=/press/bank/1/7<br />
output7audioi2cbit=7<br />
input7announcemediatype=jpg<br />
input7announcemediafile=/home/pi/tmp/input7.jpg<br />
input7announcemediaduration=3</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Repeater_Controller_configuration&diff=12569Repeater Controller configuration2026-05-11T19:24:25Z<p>G8GKQ: /* TX key and Power Saving logic - also in SSH menu (see above for description) */</p>
<hr />
<div> Back to [[Repeater Controller|repeater controller]] main page<br />
<br />
This page describes the setup of the BATC repeater controller - it should only be attempted by advanced users.<br />
<br />
'''Note not all functions listed in the config file are currently implemented.<br />
'''<br />
=SSH Menu=<br />
<br />
Some configuration and some real-time control is possible using the ssh Console Menu.<br />
<br />
To enter the repeater controller menu log in to the RPi by SSH using a program such as Putty and type menu.<br />
<br />
[[File:controller main.JPG|600px]]<br />
<br />
===Reload=== <br />
<br />
Loads the configuration changes you have made and restarts the controller<br />
<br />
===1 Behaviour===<br />
<br />
1 - Audio keepalive. Some HDMI switches permanently shut down the audio channel is no audio is present. This option puts low-level white noise on the controller audio out to prevent this from happening.<br />
<br />
2 - Transmit enable. Enables transmit key line on pin xx<br />
<br />
3 - Beacon mode. Enables the controller to just run in beacon mode and ignore all inputs.<br />
<br />
4 - Power save. Enables transmit key line to be on continuously or just when the controller sees a valid input signal or when sending an ident.<br />
<br />
5 - Operating hours. Selection of transmit key line to be active continuously or just during a timed period to save power. If timed, select the start and stop times. Note time is set using UTC time, not local time.<br />
<br />
6 - Quiet hours repeat. If Timed operation was selected in menu 5, you can set if the repeater should repeat an input signal during the quiet time.<br />
<br />
7 - Quiet hours ident. If Timed operation was selected in menu 5, you can set if the repeater should send the ident signal during the quiet time.<br />
<br />
8 - Half hour. If enabled, the transmitter will only be keyed in beacon mode during the first 30 minutes of every hour and not during the 2nd half hour to save power.<br />
<br />
9 - Quad auto enable. Enables the quad display to be automatically displayed when more than 1 selected inputs are present.<br />
<br />
10 - Enable DTMF input. Enables over air DTMF control of the repeater<br />
<br />
11 - Apply changes<br />
<br />
12 - Return to main menu<br />
<br />
===2 Callsign===<br />
<br />
Entry of the repeater callsign and QRA locator for display on generated captions.<br />
<br />
===3 Inputs===<br />
<br />
1 - 7 Input. Enables priority of each input to be set<br />
<br />
8 - Input count. Set this to the total number of inputs on the video switcher - Do NOT include the controller in this number.<br />
<br />
9 - Active Hold. Determines if a higher priority input will override the currently selected input.<br />
<br />
10 - Apply<br />
<br />
11 - Main Menu<br />
<br />
===4 Control===<br />
<br />
Enables direct selection of any input source<br />
<br />
===5 Update===<br />
Check s/w version and update if needed.<br />
<br />
===6 Settings===<br />
<br />
1 - Reset factory defaults<br />
<br />
2 - Check HDMI. Lists the HDMI settings for fault finding<br />
<br />
3 - Main menu.<br />
<br />
===7 Diagnostics===<br />
<br />
===8 Reboot===<br />
<br />
Does exactly that!<br />
<br />
=Controlling the Repeater During Testing=<br />
<br />
===Stopping the Controller===<br />
<br />
The controller can be stopped by entering<br />
stop<br />
at the command line. This tells all the repeater processes to stop and should show a "Controller Software Not Running" caption on the HDMI output.<br />
<br />
===Restarting the Controller for Testing===<br />
<br />
You can restart the controller for testing by entering<br />
rptr<br />
You will see a running commentary of what the repeater is doing in the console window. However, if you close the window, the repeater will stop. You can also stop it and get back to the command prompt by pressing ctrl-c.<br />
<br />
You can start the repeater so that it runs and keeps a log of what it is doing (even if you close the controller window) by entering this command:<br />
nohup atv-rptr/utils/run_rptr_nohup_with_log.sh &<br />
Then press ctrl-c to get back to the command prompt.<br />
<br />
If you see behaviour that you want to investigate, enter<br />
stop<br />
to force the last bit of the log to be written to the file, and then enter<br />
tail -25 log.txt<br />
to see the last 25 lines of the log.<br />
<br />
Do not run the repeater for normal use using these test modes. The log file will grow over time and eventually fill the SD Card, causing the repeater to fail.<br />
<br />
===Getting Back to Normal Use===<br />
<br />
At the end of a maintenance session, you should always reboot the repeater to check that it is working properly and put it in its normal mode. Do this by typing<br />
sudo reboot now<br />
Close the SSH window, watch the repeater output and if all is well, walk away.<br />
<br />
===Advanced Commands===<br />
<br />
If you need to edit the C code, you can recompile it and run the repeater software with the command<br />
urptr<br />
This will also show you any errors if the compilation fails.<br />
<br />
If you need to troubleshoot the output display settings, use<br />
tvservice -s<br />
<br />
=Editing the config file=<br />
<br />
The configuration file is too comprehensive for all the functions to be edited from a simple menu and more advanced customisation will require the careful editing of the text file /home/pi/atv-rptr/config/repeater_config.txt<br />
<br />
===Hand edit===<br />
You can hand-edit the configuration file with the command<br />
nano atv-rptr/config/repeater_config.txt<br />
Use the arrow keys to move about (not the mouse) and save by pressing ctrl-x, y and then enter. Discard changes by simply pressing ctrl-x and then n.<br />
<br />
If it has all gone wrong, you can start again with a factory-fresh configuration file using the command<br />
cp atv-rptr/config/repeater_config.txt atv-rptr/config/repeater_config.txt.factory<br />
Note that you will lose all of your previous edits.<br />
<br />
===FTP===<br />
<br />
Use a program such as WinSCP or Filezilla and either edit the config file in the RPi directory or copy it to a local drive, edit and then transfer it back.<br />
<br />
==Actioning the changes==<br />
<br />
After editing and saving, reload the controller by using item 1 in the SSH menu.<br />
<br />
=IR Commands=<br />
<br />
Where IR Commands are used in the config file, they are in the format<br />
=protocol:code<br />
for example:<br />
outputhdmiquadcode=nec:0x18<br />
<br />
As of software update 202503030, multiple IR commands can be sent for one function by the use of commas:<br />
outputhdmiquadcode=nec:0x18,nec0x18,nec0x18<br />
This command would send code 0x18 three times with an interval of 200ms in between. Commas are only permissible in the middle of the message, not at the start or end. No spaces allowed. Max length 63 characters.<br />
<br />
=Typical config file=<br />
<br />
The following is an example of a typical config with comments on each function - some functions are also available in the SSH menu<br />
<br />
===Introduction===<br />
Text file defining behaviour and config of the BATC HDMI Repeater Design<br />
Comments must be on their own line<br />
Read at boot time and only modified from console menu or text editor except transmitenabled which is amended by dtmfkeepertxoff or dtmfkeepertxon<br />
<br />
===Station Details - also in SSH menu===<br />
callsign=GB3HV<br />
<br />
locator=IO91LD<br />
<br />
===Video output===<br />
Used to size captions and layout display only. It does NOT set the output to hdmi720, hdmi1080, pal, ntsc <br />
vidout=hdmi1080<br />
<br />
===Ident and K CW audio output===<br />
This is used to set the output port (but not the hdmi keep-alive)<br />
hdmi, jack or usb<br />
<br />
audioout=hdmi<br />
<br />
===Low level audio - also in SSH menu===<br />
Turn on low level audio noise to keep hdmi audio active? yes/no<br />
audiokeepalive=yes<br />
<br />
audiokeepalivelevel=85<br />
<br />
===TX key and Power Saving logic - also in SSH menu (see above for description)===<br />
Enable/disable transmit ptt active? yes/no<br />
transmitenabled=yes<br />
<br />
Beacon mode only transmits carousel with ident. Set to no for rptr operation. yes/no<br />
beaconmode=no<br />
<br />
Continuous TX or power-saving. no/yes<br />
transmitwhennotinuse=yes<br />
<br />
Only transmit when input active. no/yes<br />
minimisetx=no<br />
<br />
Control mains switch for rack (and allocate GPIOs?). Not not compatible with use of input 7<br />
rackmainscontrol=yes<br />
<br />
GPIO pins for controlled rack shutdown (front panel button, shutdown signal and mains switch<br />
racksdbuttongpiopin=21<br />
racksdsignalgpiopin=24<br />
rackmainspwrgpiopin=15<br />
<br />
Turn off receiver rack and encoder to save power? Times UTC<br />
rackpowersave=yes<br />
rackpoweron1=1500<br />
rackpoweroff1=2300<br />
Set second times to be equal for one power-on period only<br />
rackpoweron2=0000<br />
rackpoweroff2=0000<br />
<br />
Continuous operation or active hours only. yes/no<br />
24houroperation=yes<br />
<br />
Power save during second half hour in active hours? Default no.<br />
Repeat and Ident are available/active during this time<br />
halfhourpowersave=no<br />
<br />
Operating times are UTC. Ignored for 24/7 operation<br />
operatingtimestart=1300<br />
<br />
operatingtimefinish=2330<br />
<br />
Quiet hours behaviour:<br />
repeatduringquiethours=no<br />
<br />
identduringquiethours=no<br />
<br />
===Transmit PTT Demand physical pin===<br />
Recommended pin 40<br />
pttgpiopin=40<br />
<br />
===Front Panel Shutdown Enabled?===<br />
Physical GPIO Pin (recommended 26)<br />
<br />
fpshutdown=no<br />
<br />
fpsdgpiopin=26<br />
<br />
===DTMF repeater control===<br />
<br />
Uses white "Portsdown/Langstone" USB dongle input<br />
<br />
These are just example commands - see [[DATV repeater DTMF commands]] for more details<br />
<br />
Control is on/off. Gain is %. Timeout is in seconds<br />
<br />
dtmfcontrol=on<br />
<br />
dtmfaudiogain=62<br />
<br />
dtmfactiontimeout=600<br />
<br />
<br />
'''All dtmf codes are of the format *xx#.''' Only xx isdefined below. Examples:<br />
<br />
dtmfreset=00<br />
<br />
To display the controller status screen - includes GPIO pin status (see below)<br />
<br />
dtmfstatusview=01<br />
<br />
Select quad view<br />
<br />
dtmfquadview=04<br />
<br />
Select input (when finished, use *00# to return to normal operation)<br />
<br />
dtmfselectinput0=10<br />
<br />
dtmfselectinput1=11<br />
<br />
dtmfselectinput2=12<br />
<br />
dtmfselectinput3=13<br />
<br />
dtmfselectinput4=14<br />
<br />
dtmfselectinput5=15<br />
<br />
dtmfselectinput6=16<br />
<br />
dtmfselectinput7=17<br />
<br />
===DTMF Keeper codes===<br />
'''In this example''' keeper codes are 5 digit and must start with 9 (*9xxxx#)<br />
<br />
Turns Tx key on / off<br />
<br />
dtmfkeepertxoff=97350<br />
<br />
dtmfkeepertxon=97351<br />
<br />
Reboot controller<br />
<br />
dtmfkeeperreboot=97359<br />
<br />
===DTMF Accessory Control examples===<br />
DTMF input can also be used to control external equipment via the GPIO pins - a maximum of 10 devices can be connected.<br />
<br />
Number of outputs<br />
<br />
dtmfoutputs=1<br />
<br />
Pin allocations<br />
<br />
dtmfgpioout1pin=8<br />
<br />
Label for status screen<br />
<br />
dtmfgpioout1label=shack_light<br />
<br />
DTMF commands to turn on and off<br />
<br />
dtmfgpioout1on=31<br />
<br />
dtmfgpioout1off=41<br />
<br />
===GPIO inputs===<br />
The controller can monitor GPIO pins and display their status on the status screen, displayed by DTMF *01# Note: Due to an error in coding, these functions are called "dtmf"gpio inputs.<br />
<br />
Number of inputs<br />
<br />
dtmfinputs=1<br />
<br />
Pin allocationa<br />
<br />
dtmfgpioin1pin=8<br />
<br />
Label for status screen<br />
dtmfgpioin1label=cabinet_door<br />
<br />
===Background image for Caption Slides===<br />
Caption cards such as "K" and input identification are built by the controller on this back ground - to change this, replace the .jpg with a different file of the same resolution<br />
<br />
backimage=/home/pi/atv-rptr/media/batc_background.jpg<br />
<br />
===Ident info===<br />
<br />
Audio is on/off, Pitch in Hz, speed in wpm, level is %<br />
<br />
identinterval=900<br />
<br />
identmediatype=jpg<br />
<br />
identmediaduration=5<br />
<br />
identmediafile=/home/pi/tmp/ident.jpg<br />
<br />
identcwaudio=on<br />
<br />
identcwspeed=15<br />
<br />
identcwpitch=800<br />
<br />
identcwlevel=50<br />
<br />
identcwfile=/home/pi/tmp/ident.wav<br />
<br />
===K information===<br />
Pitch in Hz, speed in wpm, level is %<br />
kmediatype=jpg<br />
<br />
kmediaduration=5<br />
<br />
kmediafile=/home/pi/tmp/k.jpg<br />
<br />
kcwaudio=on<br />
<br />
kcwspeed=20<br />
<br />
kcwpitch=800<br />
<br />
kcwlevel=50<br />
<br />
kcwfile=/home/pi/tmp/k.wav<br />
<br />
===Carousel information=== <br />
The carousel can have up to 99 scenes. Each scene can either be jpg, (mp4 not implemented in current release), status screen or a video source on the switcher. Jpeg images are read each time the file is displayed. For a video source, "file" is source number which can be an individual source or the multi grid, if supported by the video switch.<br />
<br />
carouselscenes=5<br />
<br />
carousel01mediatype=jpg<br />
carousel01file=/home/pi/atv-rptr/media/HVtest.jpg<br />
carousel01mediaduration=10<br />
<br />
carousel02mediatype=jpg<br />
carousel02file=/home/pi/atv-rptr/media/weather.JPG<br />
carousel02mediaduration=10<br />
<br />
carousel03mediatype=jpg<br />
carousel03file=/home/pi/atv-rptr/media/75cbw.jpg<br />
carousel03mediaduration=5<br />
<br />
carousel04mediatype=jpg<br />
carousel04file=/home/pi/custom_media/tropo.JPG<br />
carousel04mediaduration=10<br />
<br />
carousel05mediatype=source<br />
carousel05file=4<br />
carousel05mediaduration=30<br />
The example above has 4 images and one source (so 5 scenes). The 5th scene is the quad view; source 4 is set up below to show the Quad to enable its inclusion in the carousel. <br />
<br />
Note that the 4th image above is located in the /home/pi/custom_media folder. It is recommended that site-specific images are saved in that folder, which will not be over-written during software updates.<br />
<br />
===Analogue Talkback Audio on Carousel===<br />
<br />
If using an i2c analogue audio switcher, the talkback audio can be enabled during the carousel<br />
<br />
# Analogue talkback audio (144.75) can be turned on or off using the MCP23008 i2c switcher<br />
talkbackaudio=on<br />
talkbackaudioi2cbit=7<br />
<br />
If using hdmi audio, the talkback can be input on the USB mic dongle (along with the DTMF) and output on the HDMI audio during the carousel. The audio gain is set by the dtmfaudiogain parameter as they both use the same input. Facility introduced in release 202402190.<br />
<br />
# Talkback audio on DTMF input can also be output on the controller (k/cw ident) audio channel<br />
# Volume is set by dtmfaudiogain above<br />
controllertalkbackaudio=on<br />
<br />
===Input configuration===<br />
<br />
Recommended gpio pins for "input active" are 32, 35, 18, 22, 16, 19 and 21. The availableinputs number must be set to the number of possibly active (external, in addition to the controller) video sources. activeinputhold (yes/no) means that lower priority inputs do not get replaced by higher priority active inputs (except priority 1 inputs). If showquadformultipleinputs is set to yes, then the quad is sleected when 2 or more if its inputs are active.<br />
<br />
Cascaded switches refers to whether 2 4-input switches are daisy chaned t get 7 (controller plus 6 external) inputs.<br />
<br />
availableinputs=6<br />
activeinputhold=no<br />
showquadformultipleinputs=yes<br />
cascadedswitches=no<br />
<br />
===Output video switch config===<br />
<br />
The output video switch configuration is defined by this block. The switching method is defined by outputswitchcontrol=. This can be ir, gpio or html. For ir or html, the gpio outputs can also be active if showoutputongpio= is set to yes.<br />
<br />
The ir code to reset the hdmi switch (not currently used) is set in outputhdmiresetcode. The ir code to select a second (daisy-chained) hdmi switch is set in output2ndhdmicode. The ir code to select a quad view is set in outputhdmiquadcode.<br />
<br />
The outputi2caddress is the base address for an i2c video switch, and the outputi2cquadchannel is the quad select for an i2c video switch. Neither of these codes are currently implemented.<br />
<br />
outputswitchcontrol=ir<br />
showoutputongpio=yes<br />
outputhdmiresetcode=nec:0x17<br />
output2ndhdmicode=nec:0x17<br />
outputhdmiquadcode=nec:0x18<br />
outputi2caddress=3<br />
outputi2cquadchannel=9<br />
<br />
===Bitfocus Companion Server Settings===<br />
<br />
# Bitfocus Companion (html) server address & port (no trailing slash)<br />
networkctrlurl=http://192.0.1.176:8888<br />
# Other net commands have leading slash<br />
outputquadnetcommand=/press/bank/1/11<br />
<br />
===Configure input 0 - always allocated to controller===<br />
<br />
The configuration for the controller output 6 elements (currently).<br />
<br />
The input0name is the text name displayed on the Configuration screen.<br />
<br />
The IR code required to select the controller video and send it to the repeater output is stated in output0code. The format is protocol:hex code. A 2 is added to the beginning of the string if the the input is on the second, daisy-chained, hdmi switch (ie 2nec:0x17). If GPIO switching of outputs is used, the output0hdmiswitchpin indicates which pin should be used. If an i2c-controlled video switcher is used, output0i2cchannel indicates which channel should be selected to display that input. Similarly, if network commands are being used to control an ATEM switch through BitFocus companion, the tail end of the network command is defined by output0netcommand.<br />
<br />
For audio i2c switching, the correct bit is set by output0audioi2cbit.<br />
<br />
input0name=Controller<br />
output0code=nec:0x17<br />
#output0code=2nec:0x17 (daisy chain)<br />
output0hdmiswitchpin=36<br />
output0i2cchannel=1<br />
output0netcommand=/press/bank/1/8<br />
output0audioi2cbit=0<br />
<br />
===Configuration of External Inputs===<br />
<br />
The configuration for each input has 11 elements (currently).<br />
<br />
The inputxname is the text name displayed on the "announce" caption and on the Configuration screen. The priority level can be set from 1 to 9. A priority level of 9 means that the input is not displayed unless it is viewed as part of the quad or is directly selected by a DTMF command.<br />
<br />
The inputxactivegpiopin is the physical pin number that the attached receiver sets high to indicate that a signal is present. The IR code required to select the input and send it to the repeater output is stated in outputxcode. The format is protocol:hex code. A 2 is added to the beginning of the string if the the input is on the second, daisy-chained, hdmi switch (ie 2nec:0x12). If GPIO switching of outputs is used, the outputxhdmiswitchpin indicates which pin should be used. If an i2c-controlled video switcher is used, outputxi2cchannel indicates which channel should be selected to display that input. Similarly, if network commands are being used to control an ATEM switch through BitFocus companion, the tail end of the network command is defined by outputxnetcommand.<br />
<br />
For audio i2c switching, the correct bit is set by outputxaudioi2cbit.<br />
<br />
The default announce media settings work with the captions that are generated during repeater start-up. The can be cahnge for custom media if required.<br />
<br />
===Configure input 1===<br />
<br />
input1name=Stream Input<br />
input1prioritylevel=1<br />
input1activegpiopin=32<br />
output1code=nec:0x12<br />
output1hdmiswitchpin=37<br />
output1i2cchannel=2<br />
output1netcommand=/press/bank/1/1<br />
output1audioi2cbit=1<br />
input1announcemediatype=jpg<br />
input1announcemediafile=/home/pi/tmp/input1.jpg<br />
input1announcemediaduration=3<br />
<br />
===Configure input 2===<br />
<br />
input2name=QO-100 RX<br />
input2prioritylevel=2<br />
input2activegpiopin=35<br />
output2code=nec:0x59<br />
output2hdmiswitchpin=38<br />
output2i2cchannel=3<br />
output2netcommand=/press/bank/1/2<br />
output2audioi2cbit=2<br />
input2announcemediatype=jpg<br />
input2announcemediafile=/home/pi/tmp/input2.jpg<br />
input2announcemediaduration=3<br />
<br />
===Configure input 3===<br />
<br />
input3name=3.4 GHz Ryde<br />
input3prioritylevel=3<br />
input3activegpiopin=18<br />
output3code=nec:0x08<br />
output3hdmiswitchpin=33<br />
output3i2cchannel=4<br />
output3netcommand=/press/bank/1/3<br />
output3audioi2cbit=3<br />
input3announcemediatype=jpg<br />
input3announcemediafile=/home/pi/tmp/input3.jpg<br />
input3announcemediaduration=3<br />
<br />
===Configure input 4===<br />
Input 4 is set to display the quad view. This enables it to be included in the carousel (as source 4).<br />
<br />
input4name=Quad View<br />
input4prioritylevel=7<br />
input4activegpiopin=22<br />
output4code=nec:0x18<br />
#output4code=2nec:0x12 (daisy chain, not quad)<br />
output4hdmiswitchpin=31<br />
output4i2cchannel=5<br />
output4netcommand=/press/bank/1/4<br />
output4audioi2cbit=4<br />
input4announcemediatype=jpg<br />
input4announcemediafile=/home/pi/tmp/input4.jpg<br />
input4announcemediaduration=3<br />
<br />
===Configure input 5===<br />
<br />
input5name=Mast Camera<br />
input5prioritylevel=7<br />
input5activegpiopin=16<br />
output5code=2nec:0x59<br />
output5hdmiswitchpin=29<br />
output5i2cchannel=6<br />
output5netcommand=/press/bank/1/5<br />
output5audioi2cbit=5<br />
input5announcemediatype=jpg<br />
input5announcemediafile=/home/pi/tmp/input5.jpg<br />
input5announcemediaduration=10<br />
<br />
===Configure input 6===<br />
<br />
input6name=Unused 6<br />
input6prioritylevel=9<br />
input6activegpiopin=19<br />
output6code=2nec:0x08<br />
#output6code=2nec:0x08 (daisy chain)<br />
output6hdmiswitchpin=23<br />
output6i2cchannel=7<br />
output6netcommand=/press/bank/1/6<br />
output6audioi2cbit=6<br />
input6announcemediatype=jpg<br />
input6announcemediafile=/home/pi/tmp/input6.jpg<br />
input6announcemediaduration=3<br />
<br />
===Configure input 7===<br />
<br />
input7name=Unused 7<br />
input7prioritylevel=9<br />
input7activegpiopin=21<br />
output7code=2nec:0x08<br />
#output7code=2nec:0x12 (daisy chain)<br />
output7hdmiswitchpin=24<br />
output7i2cchannel=8<br />
output7netcommand=/press/bank/1/7<br />
output7audioi2cbit=7<br />
input7announcemediatype=jpg<br />
input7announcemediafile=/home/pi/tmp/input7.jpg<br />
input7announcemediaduration=3</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12473The Muntjac SDR2026-05-03T18:24:11Z<p>G8GKQ: /* Using the Third Harmonic of the Low Band for DATV on 23cm */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
Please put any comments, questions or problems on the BATC Muntjac forum: '''https://forum.batc.org.uk/viewforum.php?f=148'''<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version. After a few seconds for initialisation, the main LED will light steady.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square pad and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
nc -kluv 9979<br />
<br />
The status is updated every second and should look something like this:<br />
<br />
======================================<br />
muntjacsdr_dvb-1v0m Portsdown driver version.<br />
muntjac4_pico-1v0p Muntjac firmware version.<br />
In: videots The driver transport stream input device.<br />
Out: /dev/ttyMJ0 The Muntjac device name.<br />
-------------------<br />
FR:2486.500 PWR:3 S:333 FEC:2/3 C:4 Main frequency and parameters.<br />
FR:780.000 PWR:26 Carrier This line appears when mixing.<br />
FT:146.500 The target frequency.<br />
-------------------------------------- <br />
Packets Frames Panic Nulls MJ Panic frames are inserted to prevent<br />
In Out Frames SR333 Errors the Muntjac from running out of data.<br />
-------------------------------------- Nulls SR333 are inserted to maintain <br />
4753 176 11 4 0 an output of 333333kS from an input of <br />
====================================== 333000.<br />
<br />
MJ0: [Muntjac4-1v0p:E46164855B404B30 (BUFFER_LOW:2046)]<br />
<br />
You may occasionally see a BUFFER_LOW message from the Muntjac. Some of the input modes <br />
are not completely constant bit rate in the short term, especially the testcard and <br />
contest numbers. A panic frame containing a few null packets is sent to the Muntjac to<br />
stop the receiver from losing lock.<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. If you would like your calibration file added to this library, please e-mail it to G8GKQ. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected 26MHz TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Shoulders at Various Power Settings===<br />
<br />
The plots below show the effect of the power setting on the level of the shoulders at SR333. Shoulders are generally lower on 437MHz for the same power setting. <br />
<br />
[[File:Snap80a.jpg|400px]] [[File:Snap76b.jpg|400px]]<br />
<br />
[[File:Snap75c.jpg|400px]] [[File:Snap77d.jpg|400px]]<br />
<br />
The rising levels at the edges of the plots are an artefact of the Pluto band viewer, as shown by the PWR8 plot in a 10MHz bandwidth.<br />
<br />
[[File:Snap78e.jpg|400px]]<br />
<br />
<br />
===Programming the Microcontroller on the Muntjac===<br />
<br />
Muntjacs are provided pre-programmed by the BATC Shop, but this is the procedure to load a firmware update if required. <br />
<br />
1. Locate the latest compiled firmware file 'muntjac4_pico-1v**.uf2' which will be found here https://github.com/davecrump/portsdown4/blob/master/src/muntjac/muntjac4_pico-1v0p.uf2 and save it to your desktop. <br />
<br />
2. Hold down the BT button (the one nearest the SMA sockets) on the Muntjac while connecting it to your PC using its USB port. The Pico Muntjac appears as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The transfer should take about 5 seconds. The Muntjac will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB COM device. The main LED on the Muntjac will blink in morse as it reboots. This will be 'HI' for firmware version 1v0b and "MJ" plus the last letter of the firmware version for later versions of the firmware. The main LED will then go off for a few seconds while Muntjac is initialising and then light steady.<br />
<br />
4. Disconnect the Muntjac from the PC and connect it to the Portsdown. Make sure that the Muntjac is selected as the Output Device and then Select M2, Info. The Muntjac firmware version will be displayed along with the Muntjac Flash ID.<br />
<br />
===Alternative Method of Putting the Microcontroller into Firmware Update Mode===<br />
<br />
This may be useful if you've built the Muntjac into a box and cannot easily get to its buttons. <br />
<br />
1. Plug the Muntjac into a PC and it will appear as a COM port. Note that this may not work through a USB3 hub.<br />
<br />
2. Find the COM port number in device manager and open a serial terminal session to that COM port at 1200 baud, with a terminal program such as putty.<br />
<br />
3. The COM port will instantly disappear and the Muntjac will then appear as a USB drive.<br />
<br />
4. Proceed with step 3 in the section above.<br />
<br />
Note that this depends on the software already in the Muntjac being configured to do this. This approach would not work on a blank Raspberry Pi Pico board, which uses the same RP2040 microcontroller as the Muntjac.<br />
<br />
[[File:MJputty1.png|400px]]<br />
<br />
<br />
===Updating the Muntjac Firmware Using a Portsdown===<br />
<br />
If the Muntjac is built into a Portsdown system, it may not be possible to access its USB socket. A procedure is being developed to help with this.<br />
<br />
===Mixing Options===<br />
<br />
As both high and low band outputs may be active at the same time, this gives some options for using a mixer to transvert to other bands.<br />
<br />
The same DATV transmission can be made simultaneously on both bands (but NOT from a Portsdown menu), but either band can output a carrier instead and the third harmonic of the low band output can be used to mix the high band output to various frequencies.<br />
<br />
These notes are to guide experimentation. Some of the high band frequencies are outside the published specification of the AT86RF215 chip (2400-2483.5MHz). The output must be monitored for quality, stability and frequency accuracy. <br />
<br />
Any mixer output MUST be bandpass filtered for the required output frequency. This is particularly important for 23cm, where on 1270MHz for example, the required third harmonic of the low band carrier may be only 58MHz away from the target frequency.<br />
<br />
The low band carrier power is set at 26, which is nominally +11dBm. If a passive mixer is used, a Level7 (7dBm local oscillator) mixer is recommended. A suitable mixer is a MiniCircuits ADE-30+ (NOT the ADE-30W+, although that may be more suitable depending on your requirements). Mixers in the ADE series can look the same, but have different footprints, so do check carefully that any other mixer is compartible with the pcb. https://www.minicircuits.com/pdfs/ADE-30+.pdf<br />
<br />
The high and low band outputs are connected to the RF and LO ports of the mixer, which are specced at 200-3000MHz and the output is taken from the IF port, which is specced at 0-1000MHz. The output is likely to be in the range of the tens of microwatts. The 23cm band is outside the IF range, but still produces a usable output. <br />
<br />
The following frequency ranges are built into the Muntjac driver in the Portsdown. Putting the target frequency into Portsdown will automatically select the correct high and low band frequencies for mixing. <br />
<br />
{| class="wikitable"<br />
|+ Mixing Options<br />
|-<br />
! Output !! Low !! Harmonic !! High<br />
|-<br />
| 3400-3410 || 1010 || - || 2390-2400<br />
|-<br />
| 1300-1305 || 395 || 1185 || 2395-2400<br />
|-<br />
| 1270-1280 || 404 || 1212 || 2482-2492<br />
|-<br />
| 1244-1250 || 390 || 1170 || 2414-2420<br />
|-<br />
| 144-147 || 780 || 2340 || 2484-2487<br />
|-<br />
| 70.5-71.5 || 805 || 2415 || 2485.5-2486.5<br />
|-<br />
| 50-54 || 812 || 2436 || 2486-2490<br />
|-<br />
| 28-30 || 819 || 2457 || 2483-2485<br />
|}<br />
<br />
===Fitting and Using the Onboard Mixer===<br />
<br />
Details will appear here.<br />
<br />
===Using the Third Harmonic of the Low Band for DATV on 23cm===<br />
<br />
The third harmonic of 418.333 MHz can be used to transmit on 1255 MHz. The third harmonic is about 20 dB down on the fundamental, so good filtering is required. More details will appear here.<br />
<br />
[[File:Third Harmonic.jpg|400px]]<br />
<br />
''The fundamental at 418.3 MHz on the left with the 3rd harmonic on 1255 MHz on the right''<br />
<br />
===Command Line Operation===<br />
<br />
This gives full control over frequency and power on both high and low band simultaneously and enables Portsdown band viewer to be run at the same time.<br />
<br />
Details will appear here.<br />
<br />
===Muntjac Schematic===<br />
<br />
Downloadable PDF files will be available shortly.<br />
<br />
[[File:Image 2026-04-28 12-58-03.png|1080px]]<br />
<br />
<br />
===Muntjac Input/Output Connectors===<br />
<br />
The 40 pin J101 position will allow the Muntjac to connect directly to a Raspberry Pi. This will provide power and also an SPI link, which will allow higher data rates for future development. It is recommended that no connector is fitted here until the required orientation and gender is known.<br />
<br />
The 8 pin J3 position can be used for general I/O or to allow future developments to connect a WIZnet Ethernet module for applications that do not require a Raspberry Pi.<br />
<br />
The 12 pin J4 position is for general I/O. <br />
<br />
3.3v power is available on J3 and J4. The available current is yet to be determined.<br />
<br />
All Muntjac I/O pins on J3 and J4 are connected directly to the RP2040 microcontroller, so caution should be exercised regarding static and voltage levels. 3.3v is the nominal voltage level.<br />
<br />
There are no pins on J3 or J4 that connect to J101.<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem. However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
===Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12460The Muntjac SDR2026-04-28T13:02:07Z<p>G8GKQ: /* Using the Third Harmonic of the Low Band for DATV on 23cm */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
Please put any comments, questions or problems on the BATC Muntjac forum: '''https://forum.batc.org.uk/viewforum.php?f=148'''<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square pad and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
nc -kluv 9979<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. If you would like your calibration file added to this library, please e-mail it to G8GKQ. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected 26MHz TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Shoulders at Various Power Settings===<br />
<br />
The plots below show the effect of the power setting on the level of the shoulders at SR333. Shoulders are generally lower on 437MHz for the same power setting. <br />
<br />
[[File:Snap80a.jpg|400px]] [[File:Snap76b.jpg|400px]]<br />
<br />
[[File:Snap75c.jpg|400px]] [[File:Snap77d.jpg|400px]]<br />
<br />
The rising levels at the edges of the plots are an artefact of the Pluto band viewer, as shown by the PWR8 plot in a 10MHz bandwidth.<br />
<br />
[[File:Snap78e.jpg|400px]]<br />
<br />
<br />
===Programming the Microcontroller on the Muntjac===<br />
<br />
Muntjacs are provided pre-programmed by the BATC Shop, but this is the procedure to load a firmware update if required. <br />
<br />
1. Locate the latest compiled firmware file 'muntjac4_pico-1v**.uf2' which will be found here https://github.com/davecrump/portsdown4/blob/master/src/muntjac/muntjac4_pico-1v0p.uf2 and save it to your desktop. <br />
<br />
2. Hold down the BT button (the one nearest the SMA sockets) on the Muntjac while connecting it to your PC using its USB port. The Pico Muntjac appears as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The Muntjac will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB COM device. The main LED on the Muntjac will blink in morse as it reboots. This will be 'HI' for firmware version 1v0b and "MJ" plus the last letter of the firmware version for later versions of the firmware.<br />
<br />
4. Disconnect the Muntjac from the PC and connect it to the Portsdown. Make sure that the Muntjac is selected as the Output Device and then Select M2, Info. The Muntjac firmware version will be displayed along with the Muntjac Flash ID.<br />
<br />
===Alternative Method of Putting the Microcontroller into Firmware Update Mode===<br />
<br />
This may be useful if you've built the Muntjac into a box and cannot easily get to its buttons. <br />
<br />
1. Plug the Muntjac into a PC and it will appear as a COM port. Note that this may not work through a USB3 hub.<br />
<br />
2. Find the COM port number in device manager and open a serial terminal session to that COM port at 1200 baud, with a terminal program such as putty.<br />
<br />
3. The COM port will instantly disappear and the Muntjac will then appear as a USB drive.<br />
<br />
4. Proceed with step 3 in the section above.<br />
<br />
Note that this depends on the software already in the Muntjac being configured to do this. This approach would not work on a blank Raspberry Pi Pico board, which uses the same RP2040 microcontroller as the Muntjac.<br />
<br />
[[File:MJputty1.png|400px]]<br />
<br />
===Mixing Options===<br />
<br />
As both high and low band outputs may be active at the same time, this gives some options for using a mixer to transvert to other bands.<br />
<br />
The same DATV transmission can be made simultaneously on both bands (but NOT from a Portsdown menu), but either band can output a carrier instead and the third harmonic of the low band output can be used to mix the high band output to various frequencies.<br />
<br />
These notes are to guide experimentation. Some of the high band frequencies are outside the published specification of the AT86RF215 chip (2400-2483.5MHz). The output must be monitored for quality, stability and frequency accuracy. <br />
<br />
Any mixer output MUST be bandpass filtered for the required output frequency. This is particularly important for 23cm, where on 1270MHz for example, the required third harmonic of the low band carrier may be only 58MHz away from the target frequency.<br />
<br />
The low band carrier power is set at 26, which is nominally +11dBm. If a passive mixer is used, a Level7 (7dBm local oscillator) mixer is recommended. A suitable mixer is a MiniCircuits ADE-30+ (NOT the ADE-30W+, although that may be more suitable depending on your requirements). https://www.minicircuits.com/pdfs/ADE-30+.pdf<br />
<br />
The high and low band outputs are connected to the RF and LO ports of the mixer, which are specced at 200-3000MHz and the output is taken from the IF port, which is specced at 0-1000MHz. The output is likely to be in the range of the tens of microwatts. The 23cm band is outside the IF range, but still produces a usable output. <br />
<br />
The following frequency ranges are built into the Muntjac driver in the Portsdown. Putting the target frequency into Portsdown will automatically select the correct high and low band frequencies for mixing. <br />
<br />
{| class="wikitable"<br />
|+ Mixing Options<br />
|-<br />
! Output !! Low !! Harmonic !! High<br />
|-<br />
| 3400-3410 || 1010 || - || 2390-2400<br />
|-<br />
| 1300-1305 || 395 || 1185 || 2395-2400<br />
|-<br />
| 1270-1280 || 404 || 1212 || 2482-2492<br />
|-<br />
| 1244-1250 || 390 || 1170 || 2414-2420<br />
|-<br />
| 144-147 || 780 || 2340 || 2484-2487<br />
|-<br />
| 70.5-71.5 || 805 || 2415 || 2485.5-2486.5<br />
|-<br />
| 50-54 || 812 || 2436 || 2486-2490<br />
|-<br />
| 28-30 || 819 || 2457 || 2483-2485<br />
|}<br />
<br />
===Fitting and Using the Onboard Mixer===<br />
<br />
Details will appear here.<br />
<br />
===Using the Third Harmonic of the Low Band for DATV on 23cm===<br />
<br />
The third hamonic of 418.333 MHz can be used to transmit on 1255 MHz. The third harmonic is about 20 dB down on the fundamental, so good filtering is required. More details will appear here.<br />
<br />
[[File:Third Harmonic.jpg|400px]]<br />
<br />
''The fundamental at 418.3 MHz on the left with the 3rd harmonic on 1255 MHz on the right''<br />
<br />
===Command Line Operation===<br />
<br />
This gives full control over frequency and power on both high and low band simultaneously and enables Portsdown band viewer to be run at the same time.<br />
<br />
Details will appear here.<br />
<br />
===Muntjac Schematic===<br />
<br />
Downloadable PDF files will be available shortly.<br />
<br />
[[File:Image 2026-04-28 12-58-03.png|1080px]]<br />
<br />
<br />
===Muntjac Input/Output Connectors===<br />
<br />
The 40 pin J101 position will allow the Muntjac to connect directly to a Raspberry Pi. This will provide power and also an SPI link, which will allow higher data rates for future development. It is recommended that no connector is fitted here until the required orientation and gender is known.<br />
<br />
The 8 pin J3 position can be used for general I/O or to allow future developments to connect a WIZnet Ethernet module for applications that do not require a Raspberry Pi.<br />
<br />
The 12 pin J4 position is for general I/O. <br />
<br />
3.3v power is available on J3 and J4. The available current is yet to be determined.<br />
<br />
All Muntjac I/O pins on J3 and J4 are connected directly to the RP2040 microcontroller, so caution should be exercised regarding static and voltage levels. 3.3v is the nominal voltage level.<br />
<br />
There are no pins on J3 or J4 that connect to J101.<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem. However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
===Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12459The Muntjac SDR2026-04-28T12:53:12Z<p>G8GKQ: /* Using the Third Harmonic of the Low Band for DATV on 23cm */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
Please put any comments, questions or problems on the BATC Muntjac forum: '''https://forum.batc.org.uk/viewforum.php?f=148'''<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square pad and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
nc -kluv 9979<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. If you would like your calibration file added to this library, please e-mail it to G8GKQ. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected 26MHz TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Shoulders at Various Power Settings===<br />
<br />
The plots below show the effect of the power setting on the level of the shoulders at SR333. Shoulders are generally lower on 437MHz for the same power setting. <br />
<br />
[[File:Snap80a.jpg|400px]] [[File:Snap76b.jpg|400px]]<br />
<br />
[[File:Snap75c.jpg|400px]] [[File:Snap77d.jpg|400px]]<br />
<br />
The rising levels at the edges of the plots are an artefact of the Pluto band viewer, as shown by the PWR8 plot in a 10MHz bandwidth.<br />
<br />
[[File:Snap78e.jpg|400px]]<br />
<br />
<br />
===Programming the Microcontroller on the Muntjac===<br />
<br />
Muntjacs are provided pre-programmed by the BATC Shop, but this is the procedure to load a firmware update if required. <br />
<br />
1. Locate the latest compiled firmware file 'muntjac4_pico-1v**.uf2' which will be found here https://github.com/davecrump/portsdown4/blob/master/src/muntjac/muntjac4_pico-1v0p.uf2 and save it to your desktop. <br />
<br />
2. Hold down the BT button (the one nearest the SMA sockets) on the Muntjac while connecting it to your PC using its USB port. The Pico Muntjac appears as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The Muntjac will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB COM device. The main LED on the Muntjac will blink in morse as it reboots. This will be 'HI' for firmware version 1v0b and "MJ" plus the last letter of the firmware version for later versions of the firmware.<br />
<br />
4. Disconnect the Muntjac from the PC and connect it to the Portsdown. Make sure that the Muntjac is selected as the Output Device and then Select M2, Info. The Muntjac firmware version will be displayed along with the Muntjac Flash ID.<br />
<br />
===Alternative Method of Putting the Microcontroller into Firmware Update Mode===<br />
<br />
This may be useful if you've built the Muntjac into a box and cannot easily get to its buttons. <br />
<br />
1. Plug the Muntjac into a PC and it will appear as a COM port. Note that this may not work through a USB3 hub.<br />
<br />
2. Find the COM port number in device manager and open a serial terminal session to that COM port at 1200 baud, with a terminal program such as putty.<br />
<br />
3. The COM port will instantly disappear and the Muntjac will then appear as a USB drive.<br />
<br />
4. Proceed with step 3 in the section above.<br />
<br />
Note that this depends on the software already in the Muntjac being configured to do this. This approach would not work on a blank Raspberry Pi Pico board, which uses the same RP2040 microcontroller as the Muntjac.<br />
<br />
[[File:MJputty1.png|400px]]<br />
<br />
===Mixing Options===<br />
<br />
As both high and low band outputs may be active at the same time, this gives some options for using a mixer to transvert to other bands.<br />
<br />
The same DATV transmission can be made simultaneously on both bands (but NOT from a Portsdown menu), but either band can output a carrier instead and the third harmonic of the low band output can be used to mix the high band output to various frequencies.<br />
<br />
These notes are to guide experimentation. Some of the high band frequencies are outside the published specification of the AT86RF215 chip (2400-2483.5MHz). The output must be monitored for quality, stability and frequency accuracy. <br />
<br />
Any mixer output MUST be bandpass filtered for the required output frequency. This is particularly important for 23cm, where on 1270MHz for example, the required third harmonic of the low band carrier may be only 58MHz away from the target frequency.<br />
<br />
The low band carrier power is set at 26, which is nominally +11dBm. If a passive mixer is used, a Level7 (7dBm local oscillator) mixer is recommended. A suitable mixer is a MiniCircuits ADE-30+ (NOT the ADE-30W+, although that may be more suitable depending on your requirements). https://www.minicircuits.com/pdfs/ADE-30+.pdf<br />
<br />
The high and low band outputs are connected to the RF and LO ports of the mixer, which are specced at 200-3000MHz and the output is taken from the IF port, which is specced at 0-1000MHz. The output is likely to be in the range of the tens of microwatts. The 23cm band is outside the IF range, but still produces a usable output. <br />
<br />
The following frequency ranges are built into the Muntjac driver in the Portsdown. Putting the target frequency into Portsdown will automatically select the correct high and low band frequencies for mixing. <br />
<br />
{| class="wikitable"<br />
|+ Mixing Options<br />
|-<br />
! Output !! Low !! Harmonic !! High<br />
|-<br />
| 3400-3410 || 1010 || - || 2390-2400<br />
|-<br />
| 1300-1305 || 395 || 1185 || 2395-2400<br />
|-<br />
| 1270-1280 || 404 || 1212 || 2482-2492<br />
|-<br />
| 1244-1250 || 390 || 1170 || 2414-2420<br />
|-<br />
| 144-147 || 780 || 2340 || 2484-2487<br />
|-<br />
| 70.5-71.5 || 805 || 2415 || 2485.5-2486.5<br />
|-<br />
| 50-54 || 812 || 2436 || 2486-2490<br />
|-<br />
| 28-30 || 819 || 2457 || 2483-2485<br />
|}<br />
<br />
===Fitting and Using the Onboard Mixer===<br />
<br />
Details will appear here.<br />
<br />
===Using the Third Harmonic of the Low Band for DATV on 23cm===<br />
<br />
The third hamonic of 418.333 MHz can be used to transmit on 1255 MHz. The third harmonic is about 20 dB down on the fundamental, so good filtering is required. More details will appear here.<br />
<br />
[[File:Third Harmonic.jpg|400px]]<br />
''The fundamental at 418.3 MHz on the left with the 3rd hamonic on 1255 MHz on the right''<br />
<br />
===Command Line Operation===<br />
<br />
This gives full control over frequency and power on both high and low band simultaneously and enables Portsdown band viewer to be run at the same time.<br />
<br />
Details will appear here.<br />
<br />
===Muntjac Schematic===<br />
<br />
Downloadable PDF files will be available shortly.<br />
<br />
[[File:Image 2026-04-28 12-58-03.png|1080px]]<br />
<br />
<br />
===Muntjac Input/Output Connectors===<br />
<br />
The 40 pin J101 position will allow the Muntjac to connect directly to a Raspberry Pi. This will provide power and also an SPI link, which will allow higher data rates for future development. It is recommended that no connector is fitted here until the required orientation and gender is known.<br />
<br />
The 8 pin J3 position can be used for general I/O or to allow future developments to connect a WIZnet Ethernet module for applications that do not require a Raspberry Pi.<br />
<br />
The 12 pin J4 position is for general I/O. <br />
<br />
3.3v power is available on J3 and J4. The available current is yet to be determined.<br />
<br />
All Muntjac I/O pins on J3 and J4 are connected directly to the RP2040 microcontroller, so caution should be exercised regarding static and voltage levels. 3.3v is the nominal voltage level.<br />
<br />
There are no pins on J3 or J4 that connect to J101.<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem. However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
===Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=File:Third_Harmonic.jpg&diff=12458File:Third Harmonic.jpg2026-04-28T12:50:32Z<p>G8GKQ: File uploaded with MsUpload</p>
<hr />
<div>File uploaded with MsUpload</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12447The Muntjac SDR2026-04-28T09:09:14Z<p>G8GKQ: /* Monitoring Muntjac Driver Operation */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
Please put any comments, questions or problems on the BATC Muntjac forum: '''https://forum.batc.org.uk/viewforum.php?f=148'''<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square pad and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
nc -kluv 9979<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. If you would like your calibration file added to this library, please e-mail it to G8GKQ. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected 26MHz TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Shoulders at Various Power Settings===<br />
<br />
The plots below show the effect of the power setting on the level of the shoulders at SR333. Shoulders are generally lower on 437MHz for the same power setting. <br />
<br />
[[File:Snap80a.jpg|400px]] [[File:Snap76b.jpg|400px]]<br />
<br />
[[File:Snap75c.jpg|400px]] [[File:Snap77d.jpg|400px]]<br />
<br />
The rising levels at the edges of the plots are an artefact of the Pluto band viewer, as shown by the PWR8 plot in a 10MHz bandwidth.<br />
<br />
[[File:Snap78e.jpg|400px]]<br />
<br />
<br />
===Programming the Microcontroller on the Muntjac===<br />
<br />
Muntjacs are provided pre-programmed by the BATC Shop, but this is the procedure to load a firmware update if required. <br />
<br />
1. Locate the latest compiled firmware file 'muntjac4_pico-1v**.uf2' which will be found here https://github.com/davecrump/portsdown4/blob/master/src/muntjac/muntjac4_pico-1v0p.uf2 and save it to your desktop. <br />
<br />
2. Hold down the BT button (the one nearest the SMA sockets) on the Muntjac while connecting it to your PC using its USB port. The Pico Muntjac appears as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The Muntjac will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB COM device. The main LED on the Muntjac will blink in morse as it reboots. This will be 'HI' for firmware version 1v0b and "MJ" plus the last letter of the firmware version for later versions of the firmware.<br />
<br />
4. Disconnect the Muntjac from the PC and connect it to the Portsdown. Make sure that the Muntjac is selected as the Output Device and then Select M2, Info. The Muntjac firmware version will be displayed along with the Muntjac Flash ID.<br />
<br />
===Alternative Method of Putting the Microcontroller into Firmware Update Mode===<br />
<br />
This may be useful if you've built the Muntjac into a box and cannot easily get to its buttons. <br />
<br />
1. Plug the Muntjac into a PC and it will appear as a COM port. Note that this may not work through a USB3 hub.<br />
<br />
2. Find the COM port number in device manager and open a serial terminal session to that COM port at 1200 baud, with a terminal program such as putty.<br />
<br />
3. The COM port will instantly disappear and the Muntjac will then appear as a USB drive.<br />
<br />
4. Proceed with step 3 in the section above.<br />
<br />
Note that this depends on the software already in the Muntjac being configured to do this. This approach would not work on a blank Raspberry Pi Pico board, which uses the same RP2040 microcontroller as the Muntjac.<br />
<br />
[[File:MJputty1.png|400px]]<br />
<br />
===Mixing Options===<br />
<br />
As both high and low band outputs may be active at the same time, this gives some options for using a mixer to transvert to other bands.<br />
<br />
The same DATV transmission can be made simultaneously on both bands (but NOT from a Portsdown menu), but either band can output a carrier instead and the third harmonic of the low band output can be used to mix the high band output to various frequencies.<br />
<br />
These notes are to guide experimentation. Some of the high band frequencies are outside the published specification of the AT86RF215 chip (2400-2483.5MHz). The output must be monitored for quality, stability and frequency accuracy. <br />
<br />
Any mixer output MUST be bandpass filtered for the required output frequency. This is particularly important for 23cm, where on 1270MHz for example, the required third harmonic of the low band carrier may be only 58MHz away from the target frequency.<br />
<br />
The low band carrier power is set at 26, which is nominally +11dBm. If a passive mixer is used, a Level7 (7dBm local oscillator) mixer is recommended. A suitable mixer is a MiniCircuits ADE-30+ (NOT the ADE-30W+, although that may be more suitable depending on your requirements). https://www.minicircuits.com/pdfs/ADE-30+.pdf<br />
<br />
The high and low band outputs are connected to the RF and LO ports of the mixer, which are specced at 200-3000MHz and the output is taken from the IF port, which is specced at 0-1000MHz. The output is likely to be in the range of the tens of microwatts. The 23cm band is outside the IF range, but still produces a usable output. <br />
<br />
The following frequency ranges are built into the Muntjac driver in the Portsdown. Putting the target frequency into Portsdown will automatically select the correct high and low band frequencies for mixing. <br />
<br />
{| class="wikitable"<br />
|+ Mixing Options<br />
|-<br />
! Output !! Low !! Harmonic !! High<br />
|-<br />
| 3400-3410 || 1010 || - || 2390-2400<br />
|-<br />
| 1300-1305 || 395 || 1185 || 2395-2400<br />
|-<br />
| 1270-1280 || 404 || 1212 || 2482-2492<br />
|-<br />
| 1244-1250 || 390 || 1170 || 2414-2420<br />
|-<br />
| 144-147 || 780 || 2340 || 2484-2487<br />
|-<br />
| 70.5-71.5 || 805 || 2415 || 2485.5-2486.5<br />
|-<br />
| 50-54 || 812 || 2436 || 2486-2490<br />
|-<br />
| 28-30 || 819 || 2457 || 2483-2485<br />
|}<br />
<br />
===Fitting and Using the Onboard Mixer===<br />
<br />
Details will appear here.<br />
<br />
===Using the Third Harmonic of the Low Band for DATV on 23cm===<br />
<br />
Details will appear here.<br />
<br />
===Command Line Operation===<br />
<br />
This gives full control over frequency and power on both high and low band simultaneously and enables Portsdown band viewer to be run at the same time.<br />
<br />
Details will appear here.<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem. However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
===Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12446The Muntjac SDR2026-04-27T19:41:58Z<p>G8GKQ: /* Programming the Microcontroller on the Muntjac */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
Please put any comments, questions or problems on the BATC Muntjac forum: '''https://forum.batc.org.uk/viewforum.php?f=148'''<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square pad and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. If you would like your calibration file added to this library, please e-mail it to G8GKQ. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected 26MHz TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Shoulders at Various Power Settings===<br />
<br />
The plots below show the effect of the power setting on the level of the shoulders at SR333. Shoulders are generally lower on 437MHz for the same power setting. <br />
<br />
[[File:Snap80a.jpg|400px]] [[File:Snap76b.jpg|400px]]<br />
<br />
[[File:Snap75c.jpg|400px]] [[File:Snap77d.jpg|400px]]<br />
<br />
The rising levels at the edges of the plots are an artefact of the Pluto band viewer, as shown by the PWR8 plot in a 10MHz bandwidth.<br />
<br />
[[File:Snap78e.jpg|400px]]<br />
<br />
<br />
===Programming the Microcontroller on the Muntjac===<br />
<br />
Muntjacs are provided pre-programmed by the BATC Shop, but this is the procedure to load a firmware update if required. <br />
<br />
1. Locate the latest compiled firmware file 'muntjac4_pico-1v**.uf2' which will be found here https://github.com/davecrump/portsdown4/blob/master/src/muntjac/muntjac4_pico-1v0p.uf2 and save it to your desktop. <br />
<br />
2. Hold down the BT button (the one nearest the SMA sockets) on the Muntjac while connecting it to your PC using its USB port. The Pico Muntjac appears as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The Muntjac will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB COM device. The main LED on the Muntjac will blink in morse as it reboots. This will be 'HI' for firmware version 1v0b and "MJ" plus the last letter of the firmware version for later versions of the firmware.<br />
<br />
4. Disconnect the Muntjac from the PC and connect it to the Portsdown. Make sure that the Muntjac is selected as the Output Device and then Select M2, Info. The Muntjac firmware version will be displayed along with the Muntjac Flash ID.<br />
<br />
===Alternative Method of Putting the Microcontroller into Firmware Update Mode===<br />
<br />
This may be useful if you've built the Muntjac into a box and cannot easily get to its buttons. <br />
<br />
1. Plug the Muntjac into a PC and it will appear as a COM port. Note that this may not work through a USB3 hub.<br />
<br />
2. Find the COM port number in device manager and open a serial terminal session to that COM port at 1200 baud, with a terminal program such as putty.<br />
<br />
3. The COM port will instantly disappear and the Muntjac will then appear as a USB drive.<br />
<br />
4. Proceed with step 3 in the section above.<br />
<br />
Note that this depends on the software already in the Muntjac being configured to do this. This approach would not work on a blank Raspberry Pi Pico board, which uses the same RP2040 microcontroller as the Muntjac.<br />
<br />
[[File:MJputty1.png|400px]]<br />
<br />
===Mixing Options===<br />
<br />
As both high and low band outputs may be active at the same time, this gives some options for using a mixer to transvert to other bands.<br />
<br />
The same DATV transmission can be made simultaneously on both bands (but NOT from a Portsdown menu), but either band can output a carrier instead and the third harmonic of the low band output can be used to mix the high band output to various frequencies.<br />
<br />
These notes are to guide experimentation. Some of the high band frequencies are outside the published specification of the AT86RF215 chip (2400-2483.5MHz). The output must be monitored for quality, stability and frequency accuracy. <br />
<br />
Any mixer output MUST be bandpass filtered for the required output frequency. This is particularly important for 23cm, where on 1270MHz for example, the required third harmonic of the low band carrier may be only 58MHz away from the target frequency.<br />
<br />
The low band carrier power is set at 26, which is nominally +11dBm. If a passive mixer is used, a Level7 (7dBm local oscillator) mixer is recommended. A suitable mixer is a MiniCircuits ADE-30+ (NOT the ADE-30W+, although that may be more suitable depending on your requirements). https://www.minicircuits.com/pdfs/ADE-30+.pdf<br />
<br />
The high and low band outputs are connected to the RF and LO ports of the mixer, which are specced at 200-3000MHz and the output is taken from the IF port, which is specced at 0-1000MHz. The output is likely to be in the range of the tens of microwatts. The 23cm band is outside the IF range, but still produces a usable output. <br />
<br />
The following frequency ranges are built into the Muntjac driver in the Portsdown. Putting the target frequency into Portsdown will automatically select the correct high and low band frequencies for mixing. <br />
<br />
{| class="wikitable"<br />
|+ Mixing Options<br />
|-<br />
! Output !! Low !! Harmonic !! High<br />
|-<br />
| 3400-3410 || 1010 || - || 2390-2400<br />
|-<br />
| 1300-1305 || 395 || 1185 || 2395-2400<br />
|-<br />
| 1270-1280 || 404 || 1212 || 2482-2492<br />
|-<br />
| 1244-1250 || 390 || 1170 || 2414-2420<br />
|-<br />
| 144-147 || 780 || 2340 || 2484-2487<br />
|-<br />
| 70.5-71.5 || 805 || 2415 || 2485.5-2486.5<br />
|-<br />
| 50-54 || 812 || 2436 || 2486-2490<br />
|-<br />
| 28-30 || 819 || 2457 || 2483-2485<br />
|}<br />
<br />
===Fitting and Using the Onboard Mixer===<br />
<br />
Details will appear here.<br />
<br />
===Using the Third Harmonic of the Low Band for DATV on 23cm===<br />
<br />
Details will appear here.<br />
<br />
===Command Line Operation===<br />
<br />
This gives full control over frequency and power on both high and low band simultaneously and enables Portsdown band viewer to be run at the same time.<br />
<br />
Details will appear here.<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem. However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
===Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Repeater_Controller&diff=12386Repeater Controller2026-04-25T19:59:27Z<p>G8GKQ: /* Software update */</p>
<hr />
<div>The BATC ATV Repeater Controller uses a Raspberry Pi 4 as a fully-featured, but simple-to-implement, ATV repeater controller. Every repeater is different and the controller is designed as a core logic that can be used as the basis for an ATV repeater. The design is flexible with a large number of parameters in a text editable config file so that users can configure it to meet their own needs. <br />
<br />
The controller is intended to be used with an HDMI Video switch, but can also be used with other switchers such as an ATEM Mini or older composite video designs.<br />
<br />
<br />
The outline requirement specification is here [[:media:BATC ATV repeater controller.pdf]]<br />
<br />
<br />
[[File:HDMI repeater.jpg|650px]]<br />
<br />
==Typical operation==<br />
<br />
The BATC repeater controller controls single or multiple video switchers either by InfraRed, I2C or GPIO pins. It also generates a carousel of scenes and has an on-board DTMF decoder.<br />
<br />
===Carousel===<br />
<br />
The carousel can be configured to show up to 99 scenes. The content and duration displayed of each scene is set in the configuration file and the scene can be one of the following:<br />
<br />
* Status screen generated by the controller<br />
* jpg or png images played out by the controller<br />
* Video files (in future release).<br />
* Any input on the video switcher, so can display inputs such mast cams, weather stations or Quad video displays.<br />
<br />
<br />
The still images are read each time before display so can be regularly updated by an external source such as weather maps, propagation maps or DXspots.<br />
<br />
===Valid signal input===<br />
<br />
On receipt of a valid GPIO line signal from, for example, a Ryde receiver, the controller will, key the transmitter, play an audio beep and display an image for .5 seconds indicating which input has been activated and then switch to that input. When the receiver closes, the logic will play a "K" image and optional "K" in Morse and go back to the carousel.<br />
<br />
The receiver input switching line can be directly from a Ryde receiver or an external source such as a sync detector on an analogue source. Note do NOT exceed 3.3 volts on the GPIO input.<br />
<br />
===Ident signal===<br />
<br />
In order to comply with licensing regulations, a video and/or audio ident can be generated at an interval set in the config file.<br />
<br />
===DTMF control===<br />
<br />
An on-board DTMF decoder will allow input selection by remote control and also enable GPIO pins to be toggled to enable the control of external equipment.<br />
<br />
===Power saving===<br />
<br />
To enable power saving by turning the repeater transmitter off during quiet periods, a number of options are available such as only key the transmitter when in repeat mode, do not key the transmit during the night time and only key the transmitter to display the carousel for the first 30 minutes of every hour.<br />
<br />
Additionally, the controller can provide time-based control of the power to the receivers and encoder/exciter so that they can be shut down outside operating hours. Two operating periods can be defined in the config file, and the equipment can also be shut down and restarted using a fron-panel button. A preceding shutdown signal is provided to allow proper shutdown of the Raspberry Pis. This power control uses the same GPIO pins as Input 7, so is only compatible with the use of 6 or less repeater inputs.<br />
<br />
==Repeater system sample builds==<br />
<br />
A number of example configurations are shown on this page [[Repeater system configurations]]<br />
<br />
==Hardware control==<br />
The controller will interface to the following:<br />
<br />
* Video switches via IR transmitters - up to 2 IR transmitters can be configured separately allowing multiple video switches to be cascaded.<br />
<br />
* Video switchers via hardware lines driven from the RPi GPIO lines (note 3.3v logic output)<br />
<br />
* i2c <br />
<br />
* Network control of an ATEM Mini Pro<br />
<br />
The IR, i2c and ATEM commands for each input are set in the config file.<br />
<br />
==i2c interface==<br />
<br />
The controller will support i2c video switches and relay boards in the future. I2c Interface details are here: [[DATV Repeater i2c Interface]].<br />
<br />
===i2c audio switching===<br />
<br />
Currently, the controller only supports the i2c controlled Audio switch designed for GB3SQ. <br />
<br />
Details of the 8 channel input audio switch PCB can be found here [[DATV repeater audio switch]] and a PCB is available from the BATC shop.<br />
<br />
==Configuring IR Switching==<br />
<br />
The IR codes for the video switches used on a repeater will need to be entered in the configuration file - see [[Repeater Controller configuration]]. <br />
<br />
Full details on how to read your IR commands and then configure the system are here: [[Repeater_LIRC_Configuration|Configuring IR for HDMI Switching ]]<br />
<br />
===IR Transmitter Control Circuits===<br />
<br />
Here are example IR transmitter control circuits for the single and dual switch cases:<br />
<br />
[[File:IR Control Circuit.JPG|718px]]<br />
<br />
==Configuring ATEM Switching==<br />
<br />
The controller can switch an ATEM Mini Pro connected on the LAN. Full details here [[Configuring ATEM Control]].<br />
<br />
==Customisation and configuration==<br />
<br />
While this software is designed to work "out of the box" it will need to be configured for each individual repeater. <br />
<br />
Some configurations can be done using the SSH menu and some real-time control is possible using the ssh Console Menu.<br />
<br />
For a detailed description of the configuration details see the [[Repeater Controller configuration]] page.<br />
<br />
==DTMF control==<br />
<br />
The BATC repeater controller uses an onboard DTMF detector which detects DTMF from the mic input on a USB audio dongle (using a standard Portsdown white USB dongle).<br />
<br />
Full details of the functions that can be set by DTMF and their configuration are on this page [[DATV repeater DTMF commands]]<br />
<br />
==GPIO Connections==<br />
<br />
The repeater controller uses the RPi GPIO port for the following:<br />
<br />
*Accepts up to 8 signal detect inputs<br />
<br />
*IR / I2C drive output<br />
<br />
*GPIO outputs to control video switchers.<br />
<br />
*Auxilliary equipment status monitoring inputs<br />
<br />
*Auxilliary equipment control outputs<br />
<br />
The exact pins used for each function are set in the configuration file.<br />
<br />
The Ryde signal detect line can be connected to the input pin but '''Care MUST be taken to buffer the 3.3 volt logic levels used on the Raspberry Pi GPIO pins.'''<br />
<br />
A list of GPIO connections is here: [[Repeater GPIO Connections]].<br />
<br />
==Mains Power Control==<br />
<br />
The controller includes a number of features to reduce mains power consumption and to allow safe shutdown of Raspberry Pi based receivers and the controller itself. Full details can be found here: [[Repeater Controller Power Control]].<br />
<br />
==Composite video input==<br />
<br />
In order to enable analogue receivers and equipment, such as mast cameras, to be connected to an HDMI switcher, BATC has developed a composite to HDMI converter.<br />
<br />
Based on the Ryde software running on a Pi3 or Pi4, it uses a Fushicai EasyCap and provides a high-quality converter even with noisy FM video signals.<br />
<br />
===Software===<br />
<br />
Build an SD card with the Ryde software and after updating to release 03/03/22 select Option 8 on the Settings Menu in the SSH Console Menu. <br />
<br />
Then manually edit the file /home/pi/ryde-build/cv_config.txt where you can set audio out, 16:9/4:3 and the ident caption.<br />
<br />
After rebooting with a Fushicai EasyCap connected, the HDMI output will show the Composite video input and carry the audio from the dongle.<br />
<br />
'''Note This is not a Ryde facility, the Ryde build was just a convenient starting point for the software build.'''<br />
<br />
==Switching Logic==<br />
<br />
A detailed description of the operation of the switching logic can be found here: [[Repeater Switching Logic]].<br />
<br />
==Project status==<br />
<br />
The software was put on full release at the end of March 2022.<br />
<br />
Dec 2021 - Requirement spec agreed.<br />
<br />
Jan 22 - Alpha release for testing<br />
<br />
Feb 10th 2022 - A Beta release version of the software is available for download: https://github.com/BritishAmateurTelevisionClub/atv-rptr <br />
<br />
Note this is NOT the final release and there will be bugs! Please provide feedback on the forum.<br />
<br />
Feb 15th 2022 - Feature freeze until the first release in March<br />
<br />
Marrch 2022 -First production release<br />
<br />
February 2023 - Updated to include safe shutdown and receiver/exciter power switching.<br />
<br />
===Software download===<br />
<br />
The BATC controller is available for download at https://github.com/BritishAmateurTelevisionClub/atv-rptr<br />
<br />
Please follow the instructions carefully and note the controller runs on the Buster Lite OS and not Bullseye.<br />
<br />
Depending upon demand we may sell preprogrammed SD cards in the BATC shop.<br />
<br />
===Software update===<br />
<br />
To update the repeater software to the latest version, make sure that the controller is connected to the internet and then log in by ssh. At the ssh prompt enter:<br />
<br />
stop<br />
atv-rptr/update-rptr.sh<br />
<br />
and follow the on-screen instructions. At the end of the update, the controller will reboot and recommence normal operation.<br />
<br />
===Future requirements===<br />
<br />
The following features have been identified for inclusion in future releases:<br />
<br />
* Implement battery-backed clock (for no internet/power cuts). Will serve NTP to Rydes on same network<br />
<br />
* VLC Carousel Play of videos<br />
<br />
* Full implementation of i2c accessory switch operation (Entries exist in config file, but not yet coded)<br />
<br />
* Composite video output<br />
<br />
==Further information==<br />
<br />
See https://forum.batc.org.uk/viewtopic.php?f=82&t=7750</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Repeater_Controller&diff=12385Repeater Controller2026-04-25T19:59:06Z<p>G8GKQ: /* Software download */</p>
<hr />
<div>The BATC ATV Repeater Controller uses a Raspberry Pi 4 as a fully-featured, but simple-to-implement, ATV repeater controller. Every repeater is different and the controller is designed as a core logic that can be used as the basis for an ATV repeater. The design is flexible with a large number of parameters in a text editable config file so that users can configure it to meet their own needs. <br />
<br />
The controller is intended to be used with an HDMI Video switch, but can also be used with other switchers such as an ATEM Mini or older composite video designs.<br />
<br />
<br />
The outline requirement specification is here [[:media:BATC ATV repeater controller.pdf]]<br />
<br />
<br />
[[File:HDMI repeater.jpg|650px]]<br />
<br />
==Typical operation==<br />
<br />
The BATC repeater controller controls single or multiple video switchers either by InfraRed, I2C or GPIO pins. It also generates a carousel of scenes and has an on-board DTMF decoder.<br />
<br />
===Carousel===<br />
<br />
The carousel can be configured to show up to 99 scenes. The content and duration displayed of each scene is set in the configuration file and the scene can be one of the following:<br />
<br />
* Status screen generated by the controller<br />
* jpg or png images played out by the controller<br />
* Video files (in future release).<br />
* Any input on the video switcher, so can display inputs such mast cams, weather stations or Quad video displays.<br />
<br />
<br />
The still images are read each time before display so can be regularly updated by an external source such as weather maps, propagation maps or DXspots.<br />
<br />
===Valid signal input===<br />
<br />
On receipt of a valid GPIO line signal from, for example, a Ryde receiver, the controller will, key the transmitter, play an audio beep and display an image for .5 seconds indicating which input has been activated and then switch to that input. When the receiver closes, the logic will play a "K" image and optional "K" in Morse and go back to the carousel.<br />
<br />
The receiver input switching line can be directly from a Ryde receiver or an external source such as a sync detector on an analogue source. Note do NOT exceed 3.3 volts on the GPIO input.<br />
<br />
===Ident signal===<br />
<br />
In order to comply with licensing regulations, a video and/or audio ident can be generated at an interval set in the config file.<br />
<br />
===DTMF control===<br />
<br />
An on-board DTMF decoder will allow input selection by remote control and also enable GPIO pins to be toggled to enable the control of external equipment.<br />
<br />
===Power saving===<br />
<br />
To enable power saving by turning the repeater transmitter off during quiet periods, a number of options are available such as only key the transmitter when in repeat mode, do not key the transmit during the night time and only key the transmitter to display the carousel for the first 30 minutes of every hour.<br />
<br />
Additionally, the controller can provide time-based control of the power to the receivers and encoder/exciter so that they can be shut down outside operating hours. Two operating periods can be defined in the config file, and the equipment can also be shut down and restarted using a fron-panel button. A preceding shutdown signal is provided to allow proper shutdown of the Raspberry Pis. This power control uses the same GPIO pins as Input 7, so is only compatible with the use of 6 or less repeater inputs.<br />
<br />
==Repeater system sample builds==<br />
<br />
A number of example configurations are shown on this page [[Repeater system configurations]]<br />
<br />
==Hardware control==<br />
The controller will interface to the following:<br />
<br />
* Video switches via IR transmitters - up to 2 IR transmitters can be configured separately allowing multiple video switches to be cascaded.<br />
<br />
* Video switchers via hardware lines driven from the RPi GPIO lines (note 3.3v logic output)<br />
<br />
* i2c <br />
<br />
* Network control of an ATEM Mini Pro<br />
<br />
The IR, i2c and ATEM commands for each input are set in the config file.<br />
<br />
==i2c interface==<br />
<br />
The controller will support i2c video switches and relay boards in the future. I2c Interface details are here: [[DATV Repeater i2c Interface]].<br />
<br />
===i2c audio switching===<br />
<br />
Currently, the controller only supports the i2c controlled Audio switch designed for GB3SQ. <br />
<br />
Details of the 8 channel input audio switch PCB can be found here [[DATV repeater audio switch]] and a PCB is available from the BATC shop.<br />
<br />
==Configuring IR Switching==<br />
<br />
The IR codes for the video switches used on a repeater will need to be entered in the configuration file - see [[Repeater Controller configuration]]. <br />
<br />
Full details on how to read your IR commands and then configure the system are here: [[Repeater_LIRC_Configuration|Configuring IR for HDMI Switching ]]<br />
<br />
===IR Transmitter Control Circuits===<br />
<br />
Here are example IR transmitter control circuits for the single and dual switch cases:<br />
<br />
[[File:IR Control Circuit.JPG|718px]]<br />
<br />
==Configuring ATEM Switching==<br />
<br />
The controller can switch an ATEM Mini Pro connected on the LAN. Full details here [[Configuring ATEM Control]].<br />
<br />
==Customisation and configuration==<br />
<br />
While this software is designed to work "out of the box" it will need to be configured for each individual repeater. <br />
<br />
Some configurations can be done using the SSH menu and some real-time control is possible using the ssh Console Menu.<br />
<br />
For a detailed description of the configuration details see the [[Repeater Controller configuration]] page.<br />
<br />
==DTMF control==<br />
<br />
The BATC repeater controller uses an onboard DTMF detector which detects DTMF from the mic input on a USB audio dongle (using a standard Portsdown white USB dongle).<br />
<br />
Full details of the functions that can be set by DTMF and their configuration are on this page [[DATV repeater DTMF commands]]<br />
<br />
==GPIO Connections==<br />
<br />
The repeater controller uses the RPi GPIO port for the following:<br />
<br />
*Accepts up to 8 signal detect inputs<br />
<br />
*IR / I2C drive output<br />
<br />
*GPIO outputs to control video switchers.<br />
<br />
*Auxilliary equipment status monitoring inputs<br />
<br />
*Auxilliary equipment control outputs<br />
<br />
The exact pins used for each function are set in the configuration file.<br />
<br />
The Ryde signal detect line can be connected to the input pin but '''Care MUST be taken to buffer the 3.3 volt logic levels used on the Raspberry Pi GPIO pins.'''<br />
<br />
A list of GPIO connections is here: [[Repeater GPIO Connections]].<br />
<br />
==Mains Power Control==<br />
<br />
The controller includes a number of features to reduce mains power consumption and to allow safe shutdown of Raspberry Pi based receivers and the controller itself. Full details can be found here: [[Repeater Controller Power Control]].<br />
<br />
==Composite video input==<br />
<br />
In order to enable analogue receivers and equipment, such as mast cameras, to be connected to an HDMI switcher, BATC has developed a composite to HDMI converter.<br />
<br />
Based on the Ryde software running on a Pi3 or Pi4, it uses a Fushicai EasyCap and provides a high-quality converter even with noisy FM video signals.<br />
<br />
===Software===<br />
<br />
Build an SD card with the Ryde software and after updating to release 03/03/22 select Option 8 on the Settings Menu in the SSH Console Menu. <br />
<br />
Then manually edit the file /home/pi/ryde-build/cv_config.txt where you can set audio out, 16:9/4:3 and the ident caption.<br />
<br />
After rebooting with a Fushicai EasyCap connected, the HDMI output will show the Composite video input and carry the audio from the dongle.<br />
<br />
'''Note This is not a Ryde facility, the Ryde build was just a convenient starting point for the software build.'''<br />
<br />
==Switching Logic==<br />
<br />
A detailed description of the operation of the switching logic can be found here: [[Repeater Switching Logic]].<br />
<br />
==Project status==<br />
<br />
The software was put on full release at the end of March 2022.<br />
<br />
Dec 2021 - Requirement spec agreed.<br />
<br />
Jan 22 - Alpha release for testing<br />
<br />
Feb 10th 2022 - A Beta release version of the software is available for download: https://github.com/BritishAmateurTelevisionClub/atv-rptr <br />
<br />
Note this is NOT the final release and there will be bugs! Please provide feedback on the forum.<br />
<br />
Feb 15th 2022 - Feature freeze until the first release in March<br />
<br />
Marrch 2022 -First production release<br />
<br />
February 2023 - Updated to include safe shutdown and receiver/exciter power switching.<br />
<br />
===Software download===<br />
<br />
The BATC controller is available for download at https://github.com/BritishAmateurTelevisionClub/atv-rptr<br />
<br />
Please follow the instructions carefully and note the controller runs on the Buster Lite OS and not Bullseye.<br />
<br />
Depending upon demand we may sell preprogrammed SD cards in the BATC shop.<br />
<br />
===Software update===<br />
<br />
To update the repeater software to the latest version, make sure that the controller is connected to the internet and then log in by ssh. At the ssh prompt enter:<br />
<br />
stop<br />
atv-rptr/update-rptr.sh<br />
<br />
and follow the on-screemn instructions. At the end of the update, the controller will reboot and recommence normal operation.<br />
<br />
===Future requirements===<br />
<br />
The following features have been identified for inclusion in future releases:<br />
<br />
* Implement battery-backed clock (for no internet/power cuts). Will serve NTP to Rydes on same network<br />
<br />
* VLC Carousel Play of videos<br />
<br />
* Full implementation of i2c accessory switch operation (Entries exist in config file, but not yet coded)<br />
<br />
* Composite video output<br />
<br />
==Further information==<br />
<br />
See https://forum.batc.org.uk/viewtopic.php?f=82&t=7750</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12347Portsdown 4 ISS Tracker2026-04-24T14:24:30Z<p>G8GKQ: /* Portsdown Implementation */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
'''IMPORTANT''' The ISS tracker calculates the azimuth and elevation based on the locator that you have entered for your station in the Portsdown. Check that this is set correctly!<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* '''Flip Mode Disabled'''. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* '''Flip Mode Auto'''. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* '''Flip Mode Forced'''. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* '''Flip Mode Half-flip'''. This mode is designed to cope with overhead, or near-overhead, passes where the ISS is within the dish beamwidth at apogee. Normally, such passes would need the azimuth rotator to transit 180 degrees after the ISS passed apogee, resulting in the loss of several seconds of tracking after the apogee as the demanded elevation decreased but the rotator was transiting through South while the ISS was in the East. In this mode, the tracking is normal until the ISS reaches an elevation of 80 degrees. Then the azimuth is frozen while the elevation still tracks to apogee; at apogee, the elevation enters flip mode, meaning that it continues to track the ISS through the overhead. Once the ISS descends through 80 degrees again, the azimuth control is unfrozen, but in flip mode, allowing continued tracking to the horizon.<br />
<br />
The desired flip mode must currently be selected before the pass. It is hoped to automate this in a future update.<br />
<br />
===Offsets===<br />
<br />
The 5 offset buttons are provided to allow exact alignment of the dish on the sun before ISS tracking. To achieve this, set up a Noise Meter (such as the Portsdown Lime or Pluto Noise Meter) in place of your MiniTiouner (or SDR) in your HamTV receive set-up.<br />
<br />
* Point the dish at the sun, and then use the "Offset UP" button to move it 10 - 15 degrees higher than the sun in a piece of cold sky. Zero the reading on the Noise meter.<br />
* Then press "Cancel Offset" and you should hopefully see the noise rise on the Noise Meter as Sun Noise is received.<br />
* Apply an offset of 3 or 4 degrees in each direction in turn and observe whether there is any increase in noise with the offset (indicatiing that the dish alignment needs to be adjusted) or whether is decreases in all directions (indicating correct alignment). Note that an offset of 3 or 4 degrees will need to be applied in each case to make the dish move - many rotator controllers will not move for only 1 or 2 degrees of demanded movement.<br />
* If you need to make a physical adjustment to the dish repeat the 3 steps above to confirm alignment.<br />
<br />
Any offset is applied to ISS Moon or Sun tracking in "Flip Disabled" mode. It may be applied incorrectly in Flip modes - the maths has not been tested!<br />
<br />
Good ISS reception on a 90cm dish only needs 1 - 2 dB of sun noise.<br />
<br />
===Tracking while Receiving===<br />
<br />
The tracker is designed to keep running whilst the ISS is received on the same Portsdown. Clearly no indication of dish position is provided during receive.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha<br />
<br />
===Acknowledgements===<br />
<br />
Thanks to Paul M0EYT for the original Python tracking program.</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12346Portsdown 4 ISS Tracker2026-04-21T19:55:06Z<p>G8GKQ: /* Offsets */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* '''Flip Mode Disabled'''. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* '''Flip Mode Auto'''. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* '''Flip Mode Forced'''. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* '''Flip Mode Half-flip'''. This mode is designed to cope with overhead, or near-overhead, passes where the ISS is within the dish beamwidth at apogee. Normally, such passes would need the azimuth rotator to transit 180 degrees after the ISS passed apogee, resulting in the loss of several seconds of tracking after the apogee as the demanded elevation decreased but the rotator was transiting through South while the ISS was in the East. In this mode, the tracking is normal until the ISS reaches an elevation of 80 degrees. Then the azimuth is frozen while the elevation still tracks to apogee; at apogee, the elevation enters flip mode, meaning that it continues to track the ISS through the overhead. Once the ISS descends through 80 degrees again, the azimuth control is unfrozen, but in flip mode, allowing continued tracking to the horizon.<br />
<br />
The desired flip mode must currently be selected before the pass. It is hoped to automate this in a future update.<br />
<br />
===Offsets===<br />
<br />
The 5 offset buttons are provided to allow exact alignment of the dish on the sun before ISS tracking. To achieve this, set up a Noise Meter (such as the Portsdown Lime or Pluto Noise Meter) in place of your MiniTiouner (or SDR) in your HamTV receive set-up.<br />
<br />
* Point the dish at the sun, and then use the "Offset UP" button to move it 10 - 15 degrees higher than the sun in a piece of cold sky. Zero the reading on the Noise meter.<br />
* Then press "Cancel Offset" and you should hopefully see the noise rise on the Noise Meter as Sun Noise is received.<br />
* Apply an offset of 3 or 4 degrees in each direction in turn and observe whether there is any increase in noise with the offset (indicatiing that the dish alignment needs to be adjusted) or whether is decreases in all directions (indicating correct alignment). Note that an offset of 3 or 4 degrees will need to be applied in each case to make the dish move - many rotator controllers will not move for only 1 or 2 degrees of demanded movement.<br />
* If you need to make a physical adjustment to the dish repeat the 3 steps above to confirm alignment.<br />
<br />
Any offset is applied to ISS Moon or Sun tracking in "Flip Disabled" mode. It may be applied incorrectly in Flip modes - the maths has not been tested!<br />
<br />
Good ISS reception on a 90cm dish only needs 1 - 2 dB of sun noise.<br />
<br />
===Tracking while Receiving===<br />
<br />
The tracker is designed to keep running whilst the ISS is received on the same Portsdown. Clearly no indication of dish position is provided during receive.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha<br />
<br />
===Acknowledgements===<br />
<br />
Thanks to Paul M0EYT for the original Python tracking program.</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12345Portsdown 4 ISS Tracker2026-04-21T15:37:56Z<p>G8GKQ: /* Supported HamLib Rotator Controllers */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* '''Flip Mode Disabled'''. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* '''Flip Mode Auto'''. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* '''Flip Mode Forced'''. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* '''Flip Mode Half-flip'''. This mode is designed to cope with overhead, or near-overhead, passes where the ISS is within the dish beamwidth at apogee. Normally, such passes would need the azimuth rotator to transit 180 degrees after the ISS passed apogee, resulting in the loss of several seconds of tracking after the apogee as the demanded elevation decreased but the rotator was transiting through South while the ISS was in the East. In this mode, the tracking is normal until the ISS reaches an elevation of 80 degrees. Then the azimuth is frozen while the elevation still tracks to apogee; at apogee, the elevation enters flip mode, meaning that it continues to track the ISS through the overhead. Once the ISS descends through 80 degrees again, the azimuth control is unfrozen, but in flip mode, allowing continued tracking to the horizon.<br />
<br />
The desired flip mode must currently be selected before the pass. It is hoped to automate this in a future update.<br />
<br />
===Offsets===<br />
<br />
The 5 offset buttons are provided to allow exact alignment of the dish on the sun before ISS tracking. To achieve this, set up a Noise Meter (such as the Portsdown Lime or Pluto Noise Meter) in place of your MiniTiouner (or SDR) in your HamTV receive set-up.<br />
<br />
* Point the dish at the sun, and then use the "Offset UP" button to move it 10 - 15 degrees higher than the sun in a piece of cold sky. Zero the reading on the Noise meter.<br />
* Then press "Cancel Offset" and you should hopefully see the noise rise on the Noise Meter as Sun Noise is received.<br />
* Apply an offset of 3 or 4 degrees in each direction in turn and observe whether there is any increase in noise with the offset (indicatiing that the dish alignment needs to be adjusted) or whether is decreases in all directions (indicating correct alignment). Note that an offset of 3 or 4 degrees will need to be applied in each case to make the dish move - many rotator controllers will not move for only 1 or 2 degrees of demanded movement.<br />
* If you need to make a physical adjustment to the dish repeat 3 steps above to confirm alignment.<br />
<br />
Any offset is applied to ISS Moon or Sun tracking in "Flip Disabled" mode. It may be applied incorrectly in Flip modes - the maths has not been tested!<br />
<br />
Good ISS reception on a 90cm dish only needs 1 - 2 dB of sun noise.<br />
<br />
===Tracking while Receiving===<br />
<br />
The tracker is designed to keep running whilst the ISS is received on the same Portsdown. Clearly no indication of dish position is provided during receive.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha<br />
<br />
===Acknowledgements===<br />
<br />
Thanks to Paul M0EYT for the original Python tracking program.</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12344Portsdown 4 ISS Tracker2026-04-21T15:36:57Z<p>G8GKQ: /* Offsets */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* '''Flip Mode Disabled'''. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* '''Flip Mode Auto'''. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* '''Flip Mode Forced'''. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* '''Flip Mode Half-flip'''. This mode is designed to cope with overhead, or near-overhead, passes where the ISS is within the dish beamwidth at apogee. Normally, such passes would need the azimuth rotator to transit 180 degrees after the ISS passed apogee, resulting in the loss of several seconds of tracking after the apogee as the demanded elevation decreased but the rotator was transiting through South while the ISS was in the East. In this mode, the tracking is normal until the ISS reaches an elevation of 80 degrees. Then the azimuth is frozen while the elevation still tracks to apogee; at apogee, the elevation enters flip mode, meaning that it continues to track the ISS through the overhead. Once the ISS descends through 80 degrees again, the azimuth control is unfrozen, but in flip mode, allowing continued tracking to the horizon.<br />
<br />
The desired flip mode must currently be selected before the pass. It is hoped to automate this in a future update.<br />
<br />
===Offsets===<br />
<br />
The 5 offset buttons are provided to allow exact alignment of the dish on the sun before ISS tracking. To achieve this, set up a Noise Meter (such as the Portsdown Lime or Pluto Noise Meter) in place of your MiniTiouner (or SDR) in your HamTV receive set-up.<br />
<br />
* Point the dish at the sun, and then use the "Offset UP" button to move it 10 - 15 degrees higher than the sun in a piece of cold sky. Zero the reading on the Noise meter.<br />
* Then press "Cancel Offset" and you should hopefully see the noise rise on the Noise Meter as Sun Noise is received.<br />
* Apply an offset of 3 or 4 degrees in each direction in turn and observe whether there is any increase in noise with the offset (indicatiing that the dish alignment needs to be adjusted) or whether is decreases in all directions (indicating correct alignment). Note that an offset of 3 or 4 degrees will need to be applied in each case to make the dish move - many rotator controllers will not move for only 1 or 2 degrees of demanded movement.<br />
* If you need to make a physical adjustment to the dish repeat 3 steps above to confirm alignment.<br />
<br />
Any offset is applied to ISS Moon or Sun tracking in "Flip Disabled" mode. It may be applied incorrectly in Flip modes - the maths has not been tested!<br />
<br />
Good ISS reception on a 90cm dish only needs 1 - 2 dB of sun noise.<br />
<br />
===Tracking while Receiving===<br />
<br />
The tracker is designed to keep running whilst the ISS is received on the same Portsdown. Clearly no indication of dish position is provided during receive.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12343Portsdown 4 ISS Tracker2026-04-21T15:35:29Z<p>G8GKQ: /* Offsets */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* '''Flip Mode Disabled'''. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* '''Flip Mode Auto'''. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* '''Flip Mode Forced'''. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* '''Flip Mode Half-flip'''. This mode is designed to cope with overhead, or near-overhead, passes where the ISS is within the dish beamwidth at apogee. Normally, such passes would need the azimuth rotator to transit 180 degrees after the ISS passed apogee, resulting in the loss of several seconds of tracking after the apogee as the demanded elevation decreased but the rotator was transiting through South while the ISS was in the East. In this mode, the tracking is normal until the ISS reaches an elevation of 80 degrees. Then the azimuth is frozen while the elevation still tracks to apogee; at apogee, the elevation enters flip mode, meaning that it continues to track the ISS through the overhead. Once the ISS descends through 80 degrees again, the azimuth control is unfrozen, but in flip mode, allowing continued tracking to the horizon.<br />
<br />
The desired flip mode must currently be selected before the pass. It is hoped to automate this in a future update.<br />
<br />
===Offsets===<br />
<br />
The 5 offset buttons are provided to allow exact alignment of the dish on the sun before ISS tracking. To achieve this, set up a Noise Meter (such as the Portsdown Lime or Pluto Noise Meter) in place of your MiniTiouner (or SDR) in your HamTV receive set-up.<br />
<br />
* Point the dish at the sun, and then use the "Offset UP" button to move it 10 - 15 degrees higher than the sun in a piece of cold sky. Zero the reading on the Noise meter.<br />
* Then press "Cancel Offset" and you should hopefully see the noise rise on the Noise Meter as Sun Noise is received.<br />
* Apply an offset of 3 or 4 degrees in each direction in turn and observe whether there is any increase in noise with the offset (indicatiing that the dish alignment needs to be adjusted) or whether is decreases in all directions (indicating correct alignment). Note that an offset of 3 or 4 degrees will need to be applied in each case to make the dish move - many rotator controllers will not move for only 1 or 2 degrees of demanded movement.<br />
* If you need to make a physical adjustment to the dish repeat 3 steps above to confirm alignment.<br />
<br />
Any offset is applied to ISS Moon or Sun tracking in "Flip Disabled" mode. It may be applied incorrectly in Flip modes - the maths has not been tested!<br />
<br />
Good ISS reception on a 90cm dish only needs 1 - 2 dB of sun noise.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12342Portsdown 4 ISS Tracker2026-04-21T15:19:39Z<p>G8GKQ: /* Offsets */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* '''Flip Mode Disabled'''. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* '''Flip Mode Auto'''. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* '''Flip Mode Forced'''. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* '''Flip Mode Half-flip'''. This mode is designed to cope with overhead, or near-overhead, passes where the ISS is within the dish beamwidth at apogee. Normally, such passes would need the azimuth rotator to transit 180 degrees after the ISS passed apogee, resulting in the loss of several seconds of tracking after the apogee as the demanded elevation decreased but the rotator was transiting through South while the ISS was in the East. In this mode, the tracking is normal until the ISS reaches an elevation of 80 degrees. Then the azimuth is frozen while the elevation still tracks to apogee; at apogee, the elevation enters flip mode, meaning that it continues to track the ISS through the overhead. Once the ISS descends through 80 degrees again, the azimuth control is unfrozen, but in flip mode, allowing continued tracking to the horizon.<br />
<br />
The desired flip mode must currently be selected before the pass. It is hoped to automate this in a future update.<br />
<br />
===Offsets===<br />
<br />
The 5 offset buttons are provided to allow exact alignment of the dish on the sun before use for ISS tracking.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12341Portsdown 4 ISS Tracker2026-04-21T15:18:45Z<p>G8GKQ: /* Details */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* '''Flip Mode Disabled'''. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* '''Flip Mode Auto'''. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* '''Flip Mode Forced'''. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* '''Flip Mode Half-flip'''. This mode is designed to cope with overhead, or near-overhead, passes where the ISS is within the dish beamwidth at apogee. Normally, such passes would need the azimuth rotator to transit 180 degrees after the ISS passed apogee, resulting in the loss of several seconds of tracking after the apogee as the demanded elevation decreased but the rotator was transiting through South while the ISS was in the East. In this mode, the tracking is normal until the ISS reaches an elevation of 80 degrees. Then the azimuth is frozen while the elevation still tracks to apogee; at apogee, the elevation enters flip mode, meaning that it continues to track the ISS through the overhead. Once the ISS descends through 80 degrees again, the azimuth control is unfrozen, but in flip mode, allowing continued tracking to the horizon.<br />
<br />
The desired flip mode must currently be selected before the pass. It is hoped to automate this in a future update.<br />
<br />
===Offsets===<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12340Portsdown 4 ISS Tracker2026-04-21T15:18:37Z<p>G8GKQ: /* Flip Mode */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* '''Flip Mode Disabled'''. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* '''Flip Mode Auto'''. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* '''Flip Mode Forced'''. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* '''Flip Mode Half-flip'''. This mode is designed to cope with overhead, or near-overhead, passes where the ISS is within the dish beamwidth at apogee. Normally, such passes would need the azimuth rotator to transit 180 degrees after the ISS passed apogee, resulting in the loss of several seconds of tracking after the apogee as the demanded elevation decreased but the rotator was transiting through South while the ISS was in the East. In this mode, the tracking is normal until the ISS reaches an elevation of 80 degrees. Then the azimuth is frozen while the elevation still tracks to apogee; at apogee, the elevation enters flip mode, meaning that it continues to track the ISS through the overhead. Once the ISS descends through 80 degrees again, the azimuth control is unfrozen, but in flip mode, allowing continued tracking to the horizon.<br />
<br />
The desired flip mode must currently be selected before the pass. It is hoped to automate this in a future update.<br />
<br />
===Offsets===<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12339Portsdown 4 ISS Tracker2026-04-21T15:18:09Z<p>G8GKQ: /* Flip Mode */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* '''Flip Mode Disabled'''. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* '''Flip Mode Auto'''. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* '''Flip Mode Forced'''. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* '''Flip Mode Half-flip'''. This mode is designed to cope with overhead, or near-overhead, passes where the ISS is within the dish beamwidth at apogee. Normally, such passes would need the azimuth rotator to transit 180 degrees after the ISS passed apogee, resulting in the loss of several seconds of tracking after the apogee as the demanded elevation decreased but the rotator was transiting through South while the ISS was in the East. In this mode, the tracking is normal until the ISS reaches an elevation of 80 degrees. Then the azimuth is frozen while the elevation still tracks to apogee; at apogee, the elevation enters flip mode, meaning that it continues to track the ISS through the overhead. Once the ISS descends through 80 degrees again, the azimuth control is unfrozen, but in flip mode, allowing continued tracking to the horizon.<br />
<br />
The desired flip mode must currently be selected before the pass. It is hoped to automate this in a future update.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12338Portsdown 4 ISS Tracker2026-04-21T14:22:10Z<p>G8GKQ: /* Portsdown Implementation */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Details===<br />
<br />
Selecting "Track Moon", "Track ISS" or "Track Sun" will always display the current position of the object in the sky. When "Stop" or "Park" are selected, the display of Demanded Position may not be valid. If using the g5500pi controller, the actual position of the dish is also displayed when "Track Moon", "Track ISS" or "Track Sun" is selected. It is hoped to extend this capability to HamLib controllers in the future.<br />
<br />
<br />
===Flip Mode===<br />
<br />
The controller always assumes that the rotator has an end-stop at North. To cater for ISS passes that are North of the dish location, and to better cater for overhead passes, 4 Flip Modes are available. The Flip mode button cycles between these 4 modes:<br />
<br />
* Flip Mode Disabled. In this mode the maximum demanded rotator elevation will be 90 degrees. On ISS passes North of the dish location, some tracking time will be lost just after apogee as the rotator travels nearly 360 degrees to get to the other side of the North end-stop. Note that this mode is the only mode comaptible with rotators that cannot achieve more than 90 degrees elevation.<br />
<br />
* Flip Mode Auto. This mode is a placeholder for a future capability to enable unnattended auto-selection of Flip Modes. Currently it has the same function as "Flip Mode Forced" below.<br />
<br />
* Flip Mode Forced. In this mode, the azimuth is set to (demanded azimuth =/- 180 degrees) and the elevation is set to (180 - the demanded elevation). The effect of this is that the dish tracks the ISS "upside down" (beware waterproofing!) and the rotator end-stop is "moved" to South enabling continuous tracking of ISS passes North of the dish location.<br />
<br />
* Flip Mode Half-flip.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12337Portsdown 4 ISS Tracker2026-04-20T11:59:56Z<p>G8GKQ: /* Portsdown Implementation */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller, select "Set-up Controller" and enter the IP address and port of your controller in the format 192.168.2.140:8008. You may find it useful to allocate a fixed IP address in your network router for the controller.<br />
<br />
If using the HamLib controller, select "Set-up Controller" and enter the HamLib device address. This is typically in the format /dev/ttyUSB2. Next enter the model number (the number in the first column of the table below), and the baud rate (typically 9600).<br />
<br />
You should also enter the desired park position for your dish; the controller will move the dish to this position at the end of every pass. Select "Set Park Position" and enter the azimuth and elevation.<br />
<br />
The configuration settings are stored for future use.<br />
<br />
Now select "Track ISS". You should see the demanded position for the ISS displayed above the buttons, and the dish will move to track the position if it is more than 5 degrees above the horizon. Selecting "Track Moon", or "Track Sun" will also display the demanded position, and the dish will track if above 5 degrees.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12336Portsdown 4 ISS Tracker2026-04-20T11:49:26Z<p>G8GKQ: </p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12335Portsdown 4 ISS Tracker2026-04-20T11:48:58Z<p>G8GKQ: </p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller software (https://www.clearskyinstitute.com/ham/G5500/) connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12334Portsdown 4 ISS Tracker2026-04-20T11:48:33Z<p>G8GKQ: /* Portsdown Implementation */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller software connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
[[File:ISS Tracker.png|400px]]<br />
<br />
Before use, the Controller needs to be configured. Set either "Controller G5500pi" (the default) or "Controller HamLib".<br />
<br />
If using the G5500pi controller<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=File:ISS_Tracker.png&diff=12333File:ISS Tracker.png2026-04-20T11:45:18Z<p>G8GKQ: File uploaded with MsUpload</p>
<hr />
<div>File uploaded with MsUpload</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12332Portsdown 4 ISS Tracker2026-04-20T11:43:12Z<p>G8GKQ: </p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller software connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Portsdown Implementation===<br />
<br />
To access the rotator menu, go to M3, ISS HamTV RX Merger, ISS Tracker Set-up.<br />
<br />
<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12331Portsdown 4 ISS Tracker2026-04-20T11:40:50Z<p>G8GKQ: /* Supported HamLib Rotator Controllers */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller software connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib (rotctl(d), Hamlib 3.3) that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12329Portsdown 4 ISS Tracker2026-04-20T11:32:10Z<p>G8GKQ: /* Supported HamLib Rotator Controllers */</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller software connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib that supports the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4_ISS_Tracker&diff=12328Portsdown 4 ISS Tracker2026-04-20T11:31:56Z<p>G8GKQ: Created page with "The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500p..."</p>
<hr />
<div>The Portsdown 4 ISS Tracker is designed to control an az/el rotator to track the ISS during a HamTV transmission. Initial testing has been on a G5500 rotator using the g5500pi controller software connected to the rotator; however, other rotator controllers supported by HamLib rotctl may be compatible.<br />
<br />
===Supported HamLib Rotator Controllers===<br />
<br />
Portsdown 4 uses an early version of HamLib that suprts the following controllers:<br />
<br />
Rot # Mfg Model Version Status<br />
1 Hamlib Dummy 0.2 Beta<br />
2 Hamlib NET rotctl 0.3 Beta<br />
201 Hamlib EasycommI 0.4 Beta<br />
202 Hamlib EasycommII 0.4 Beta<br />
204 Hamlib EasycommIII 0.4 Alpha<br />
301 XQ2FOD Fodtrack 0.2 Stable<br />
401 Idiom Press Rotor-EZ 2010-02-14 Beta<br />
402 Idiom Press RotorCard 2010-02-14 Untested<br />
403 Hy-Gain DCU-1/DCU-1X 2010-08-23 Untested<br />
404 DF9GR ERC 2010-08-23b Alpha<br />
405 Green Heron RT-21 2014-09-14 Alpha<br />
501 SARtek SARtek-1 0.2 Untested<br />
601 Yaesu GS-232A 0.3 Beta<br />
602 Yaesu/Kenpro GS-232 0.1 Beta<br />
603 Yaesu GS-232B 0.2 Beta<br />
604 F1TE GS232/F1TE Tracker 0.1 Beta<br />
701 WA6UFQ PcRotor 0.1 Untested<br />
801 Heathkit HD 1780 Intellirotor 0.1 Beta<br />
901 SPID Rot2Prog 1.0 Stable<br />
902 SPID Rot1Prog 1.0 Stable<br />
903 SPID MD-01/02 (ROT2 mode) 1.0 Stable<br />
1001 M2 RC2800 0.1.1 Beta<br />
1101 EA4TX ARS RCI AZ&EL 0.1 Beta<br />
1102 EA4TX ARS RCI AZ 0.1 Beta<br />
1201 AMSAT IF-100 0.1 Untested<br />
1301 LA7LKA ts7400 0.1 Beta<br />
1401 Celestron NexStar 0.1 Untested<br />
1501 DG9OAA Ether6 (via ethernet) 0.1 Beta<br />
1601 CNCTRK CNCTRK 0.1 Untested<br />
1701 Prosistel Prosistel D 0.3 Beta<br />
1801 Meade LX200 0.1 Alpha</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=Portsdown_4&diff=12326Portsdown 42026-04-20T11:26:35Z<p>G8GKQ: /* Portsdown 4 test and alignment aids */</p>
<hr />
<div>The Portsdown 4 transceiver software has been specifically designed to be used with the Raspberry Pi 4 and the official Raspberry Pi 7 inch touchscreen. It will drive a Pluto SDR or the LimeSDR. <br />
<br />
Portsdown 4 is the simplest and easiest to construct, with a barebones system consisting of:<br />
<br />
* Raspberry Pi4 2GB model<br />
* 7" touch screen<br />
* 8, 16 or 32 GB SD card<br />
* Adalm Pluto '''or''' Lime SDRmini SDR hardware<br />
<br />
This will give you a DVB-S2 and DVB-T DATV transmit system from 30 to 3500 MHz when using a Lime SDR and 50MHz to 4100 MHz with the Pluto.<br />
<br />
With the addition of a MiniTiouner USB receiver [[https://wiki.batc.org.uk/MiniTioune]], you will have a full spec DVB-S/S2 DATV transceiver. <br />
<br />
With the addition of the [[Knucker|Knucker USB tuner]] you will also have DVB-T receive capabilities.<br />
<br />
==Building a Portsdown 4==<br />
<br />
Dave G8GKQ published this step by step guide to building a Portsdown 4 in CQ-TV 271:<br />
<br />
[[:media:Getting Started With Portsdown 4.pdf]]<br />
<br />
==Capabilities==<br />
<br />
===Portsdown 4 transmit capabilities:===<br />
* DVB-S, DVB-S2 and DVB-T (H264 only) transmissions from a Pluto SDR connected by USB. More details [[Portsdown_4_Pluto|here]].<br />
* DVB-S, DVB-S2 and DVB-T (MPEG-2 and H264) transmissions from a LimeSDR Mini or LimeSDR USB using stock LimeSDR firmware<br />
* DVB-S and DVB-S2 (MPEG-2 and H264) transmissions from a LimeSDR Mini using "LimeDVB" firmware<br />
* DVB-S (MPEG-2 and H264) transmissions from a DATV Express Board connected by USB<br />
* Supported transmit video sources include the Raspberry Pi Camera, C920 WebCam or a USB-connected EasyCap composite video capture device<br />
* Streaming to the BATC Streamer using the Raspberry Pi Camera or EasyCap composite video capture device as a source<br />
<br />
===Portsdown 4 receive capabilities:===<br />
When a [[MiniTioune|MiniTiouner USB receiver]] is connected via USB:<br />
* Reception and display of DVB-S and DVB-S2 (MPEG-2, H264 and H265) signals - see [[DVB-S/S2 Reception|https://wiki.batc.org.uk/DVB-S/S2_Reception]]<br />
<br />
When a [[Knucker|BATC Knucker USB tuner]] is connected by USB:<br />
* Reception and display of DVB-T and DVB-T2 (MPEG-2, H264 and H265) signals<br />
<br />
When the Portsdown 4 is connected to the internet:<br />
* Display of streams from the BATC Streamer<br />
<br />
Received audio can be heard through either the Raspberry Pi AV socket or a compatible USB audio dongle.<br />
<br />
===Portsdown 4 test and alignment aids===<br />
<br />
* Control of a Pluto, LimeSDR Mini, DATV Express, ADF4351, Elcom and SLO Microwave Sources using the [[Portsdown 4 Signal Generator]].<br />
<br />
* Basic spectrum display of band occupancy using the "[[Portsdown Band Viewer]]" - '''note this requires a LimeSDR Mini to be connected'''.<br />
<br />
===Portsdown 4 Utilities===<br />
<br />
* The Portsdown 4 can control an az/el rotator to track the ISS, sun or the moon. Full details here: [[Portsdown 4 ISS Tracker]]<br />
<br />
==Hardware==<br />
<br />
[[File:Portsdown 4 Block.PNG|600px]]<br />
<br />
Only the Raspberry Pi 4 and the Official 7 inch touchscreen (or the DFRobot DFR0550 5 inch touchscreen) are planned to be supported in the near future.<br />
<br />
===Portsdown 4 GPIO connections===<br />
<br />
Due to a reassignment of the GPIO pins on Raspberry Pi4, the connections are different to previous generations of Portsdown.<br />
<br />
The Portsdown 4 GPIO Connections are defined here: [[Portsdown 4 GPIO Connections]].<br />
<br />
===Powering the LimeSDR===<br />
<br />
The Raspberry Pi 4 has increased power capabilities on its USB ports, so it is recommended that you connect the LimeSDR directly to the Raspberry Pi. For some reason, the LimeSDR Mini sometimes works better when connected to the USB2 ports (the black ones, not the blue ones).<br />
<br />
===Powering the Pluto===<br />
<br />
The Raspberry Pi 4 has increased power capabilities on its USB ports, and the Pluto does not work well with USB Hubs, so it is recommended that you connect the Pluto directly to a USB3 port (the blue ones) on the Raspberry Pi 4. Do not use a USB hub or power the Pluto from its USB power port.<br />
<br />
The Pluto is more reliable and less likely to drop out if fed with about 4.9v on USB. So, set the RPi input voltage to 5.0v, or use another power source to make sure that the Pluto is not fed with over 5.0v.<br />
<br />
If powering the Pluto using the USB lead from the Pi you may have USB instability issues if the Pluto receives over 5V. As the Pi prefers voltages around 5.1-5.2V this can cause problems. One way around this is to carefully cut into the USB lead and add a Schottky diode (e.g. 1N5817) in series with the positive conductor. With a supply voltage of 5.15V to the Pi the Pluto receives 4.85V and both work correctly.<br />
<br />
===Portsdown hardware===<br />
<br />
Full details of the Portsdown hardware [[Portsdown hardware|are available here]].<br />
<br />
==Software==<br />
<br />
The Portsdown 4 software is available on a pre-programmed SD card which you can buy from the BATC shop https://batc.org.uk/shop/portsdown-transmitter-pre-programmed-sd-card/<br />
<br />
If you wish to build your own card the build is on GitHub at https://github.com/BritishAmateurTelevisionClub/portsdown4<br />
<br />
==Langstone Narrow Band Transceiver==<br />
<br />
The Portsdown 4 software build is also compatible with the Langstone Microwave transceiver software, which can be loaded from touchscreen selections (menu 2) AFTER the Portsdown software has been installed.<br />
<br />
See https://wiki.microwavers.org.uk/Langstone_Project for more details and the full spec of the Langstone.<br />
<br />
Note: the Langstone software needs a '''Pluto SDR''' to be connected by USB, and a compatible USB Audio dongle.<br />
<br />
==Pluto Capabilities==<br />
<br />
The Portsdown 4 support for the Pluto SDR is still under development and there are some limitations on functionality as described here [[Portsdown 4 Pluto]].<br />
<br />
==FAQ==<br />
<br />
* Is it possible to rotate the PiCam image in software as it is on it's side?<br />
No - you need to do the camera mounting modification which Colin G4KLB described in CQ-TV 267<br />
<br />
* Can I upgrade from Langstone or a previous version including Portsdown A27?<br />
No - you must start with a clean image on your SD card<br />
<br />
* When I try to update I get the error "Unable to contact GitHub for update, Internet connection to Google seems OK". The solution is to log in by ssh and run the following commands:<br />
<br />
cd /home/pi<br />
wget https://raw.githubusercontent.com/BritishAmateurTelevisionClub/portsdown4/master/update.sh -O /home/pi/update.sh<br />
chmod +x /home/pi/update.sh<br />
./update.sh<br />
<br />
* I have built my Portsdown 4 but the screen is upside down. How can I get it the right way up?<br />
<br />
Menu 3, System Config, Invert 7 inch<br />
<br />
==More information==<br />
<br />
For more information and to ask any questions see https://forum.batc.org.uk/viewtopic.php?f=103&t=6804</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=PicoTuner&diff=12317PicoTuner2026-04-20T10:52:44Z<p>G8GKQ: /* Programming the Pico */</p>
<hr />
<div>PicoTuner is a USB tuner PCB for DATV based around the Serit 4334 NIM using the RpiPico as the USB interface.<br />
<br />
The main reason for the development is to use the £5 Raspberry Pi Pico in place of the £32 FTDI USB interface on the MiniTiouner PCB. Using the Pico interface also enables 2 channels to be decoded and displayed at the same time.<br />
<br />
The PicoTuner replaces the MiniTiouner Mk2 PCB for all new builds, however limited stock of the MiniTiouner PCB and FTDI module will be held in the BATC shop for those who wish to continue to use the MiniTiouner software which is NOT compatible with PicoTuner.<br />
<br />
=Receivers compatible with PicoTuner=<br />
<br />
==OpenTuner==<br />
<br />
Version V0.9 onwards of OpenTuner by Tom ZR6TG is compatible with PicoTuner and can display 2 channels simultaneously.<br />
<br />
You will need to install the usb drivers to be able to use it with OpenTuner. Details can be found here https://www.zr6tg.co.za/2024/02/11/picotuner-an-experimental-dual-ts-alternative/<br />
<br />
Alternatively, ZR6TG has developed a simple test app that will install the windows drivers for PicoTuner. It is at beta version but available from here: https://www.dropbox.com/scl/fi/3ziiiq71hretd2yzaou8f/picotuner_driver_test_app.zip?rlkey=gl4xsxddxprxfvjjydebvez5y&dl=0<br />
<br />
- You can detect and check the drivers<br />
- Install the drivers (required admin privs - right click and run as administrator)<br />
- Check PicoTuner Version<br />
- Check github for latest version (just a check and copies directly link to uf2 in clipboard<br />
- Force Bootsel<br />
<br />
[[File:picotuner_driverinstall.png|400px]]<br />
<br />
Once PicoTuner drivers are properly installed on Windows 10, they show up in Device Manager as shown below:<br />
<br />
[[File:PicoTuner in Device Manager.JPG|200px]]<br />
<br />
==Portsdown==<br />
<br />
Version 202403110 onwards of the Portsdown 4 receiver is compatible with PicoTuner but can only display one channel.<br />
<br />
See the following pages on using the Portsdown receiver.<br />
<br />
[[Portsdown_4#Portsdown_4_receive_capabilities:|https://wiki.batc.org.uk/Portsdown_4#Portsdown_4_receive_capabilities:]] <br />
<br />
[[DVB-S/S2 Reception|https://wiki.batc.org.uk/DVB-S/S2_Reception]]<br />
<br />
==Ryde==<br />
<br />
Version 202403220 onwards of the Ryde Receiver is compatible with PicoTuner but can only display one channel.<br />
<br />
==Minitiouner software - NOT compatible==<br />
<br />
Current versions of the MiniTiouner PC software '''WILL NOT''' work with PicoTuner. As F6DZP is no longer updating Minitioune it will probably never be compatible.<br />
<br />
=PicoTuner hardware=<br />
<br />
Mike G0MJW has designed a PCB which will host the Serit NIM and Pico board. The Pico can either be a standard board or the WIZnet W5100S-EVB-Pico or W5500-EVB-Pico, which are basically a Pico with an integrated Ethernet interface.<br />
<br />
[[File:Picotuner Mk1.png|400px]]<br />
<br />
Full details are available here [[PicoTuner Hardware]]<br />
<br />
=Surface mount PicoTuner adaptor for the MiniTiouner V2 PCB=<br />
<br />
Whilst the PicoTuner was designed for use in a new tuner design it can also be retrofitted to the BATC V2 Minitiouner and similar designs providing their FTDI modules are fitted in sockets. <br />
<br />
Full details are available here: [[Surface mount PicoTuner adaptor for the MiniTiouner V2 PCB]]<br />
<br />
= Programming the Pico =<br />
<br />
The Pico can be progranmmed either before or after it is connected to the PicoTuner PCB.<br />
<br />
1. Locate the latest compiled firmware file 'PicoTuner_vxxx.uf2' which will be found here https://github.com/g4eml/PicoTuner/releases and save it to your desktop. <br />
<br />
2. Hold down the BOOTSEL button on the Pico while connecting it to your PC using its micro USB port. The Pico should appear as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The Pico will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB device.<br />
<br />
= Ethernet Interface for PicoTuner =<br />
<br />
It is possible to fit the PicoTuner with a wired Ethernet interface. This integrates an Ethernet chip with a Pico processor chip. It enables the PicoTuner to be used as a 2 receiver WinterHill, or it can be used with OpenTuner software, version 0.B or later. <br />
<br />
Status information is available over the USB serial port, but command input and transport stream output is possible only over the Ethernet connection.<br />
<br />
Full details can be found here [[PicoTuner Ethernet Interface]].<br />
<br />
= Fault-finding =<br />
<br />
When used with the Portsdown, if the message "Resetting USB Bus" appears, it generally means that power has not been applied to the Tuner. To recover from this situation, '''you MUST disconnect the USB connection, pause 5 seconds, reconnect the USB connection and then apply power''' to the tuner. Simply applying power does not solve the problem.<br />
<br />
Subsequent "Waiting for Tuner to Respond" messages can normally be cured by disconnecting the USB connection and reconnecting after 5 seconds.<br />
<br />
You can check if the USB connection is working by going to Menu 2, File Menu, List USB Devices. The BATC PicoTuner should appear in the list.</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12316The Muntjac SDR2026-04-20T10:52:02Z<p>G8GKQ: /* Programming the Microcontroller on the Muntjac */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. If you would like your calibration file added to this library, please e-mail it to G8GKQ. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Shoulders at Various Power Settings===<br />
<br />
The plots below show the effect of the power setting on the level of the shoulders at SR333. Shoulders are generally lower on 437MHz for the same power setting. <br />
<br />
[[File:Snap80a.jpg|400px]] [[File:Snap76b.jpg|400px]]<br />
<br />
[[File:Snap75c.jpg|400px]] [[File:Snap77d.jpg|400px]]<br />
<br />
The rising levels at the edges of the plots are an artefact of the Pluto band viewer, as shown by the PWR8 plot in a 10MHz bandwidth.<br />
<br />
[[File:Snap78e.jpg|400px]]<br />
<br />
===Programming the Microcontroller on the Muntjac===<br />
<br />
Muntjacs are provided pre-programmed by the BATC Shop, but this is the procedure to load a firmware update if required. <br />
<br />
1. Locate the latest compiled firmware file 'muntjac4_pico-1v**.uf2' which will be found here https://github.com/davecrump/portsdown4/blob/master/src/muntjac/muntjac4_pico-1v0b.uf2 and save it to your desktop. <br />
<br />
2. Hold down the BT button (the one nearest the output sockets) on the Muntjac while connecting it to your PC using its USB port. The Pico Muntjac appear as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The Muntjac will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB device.<br />
<br />
4. Disconnect the Muntjac from the PC and connect it to the Portsdown. Make sure that the Muntjac is selected as the Output Device and then Select M2, Info. The Muntjac firmware version will be displayed along with the Muntjac Flash ID.<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem. However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=PicoTuner&diff=12315PicoTuner2026-04-20T10:50:09Z<p>G8GKQ: /* Programming the Pico */</p>
<hr />
<div>PicoTuner is a USB tuner PCB for DATV based around the Serit 4334 NIM using the RpiPico as the USB interface.<br />
<br />
The main reason for the development is to use the £5 Raspberry Pi Pico in place of the £32 FTDI USB interface on the MiniTiouner PCB. Using the Pico interface also enables 2 channels to be decoded and displayed at the same time.<br />
<br />
The PicoTuner replaces the MiniTiouner Mk2 PCB for all new builds, however limited stock of the MiniTiouner PCB and FTDI module will be held in the BATC shop for those who wish to continue to use the MiniTiouner software which is NOT compatible with PicoTuner.<br />
<br />
=Receivers compatible with PicoTuner=<br />
<br />
==OpenTuner==<br />
<br />
Version V0.9 onwards of OpenTuner by Tom ZR6TG is compatible with PicoTuner and can display 2 channels simultaneously.<br />
<br />
You will need to install the usb drivers to be able to use it with OpenTuner. Details can be found here https://www.zr6tg.co.za/2024/02/11/picotuner-an-experimental-dual-ts-alternative/<br />
<br />
Alternatively, ZR6TG has developed a simple test app that will install the windows drivers for PicoTuner. It is at beta version but available from here: https://www.dropbox.com/scl/fi/3ziiiq71hretd2yzaou8f/picotuner_driver_test_app.zip?rlkey=gl4xsxddxprxfvjjydebvez5y&dl=0<br />
<br />
- You can detect and check the drivers<br />
- Install the drivers (required admin privs - right click and run as administrator)<br />
- Check PicoTuner Version<br />
- Check github for latest version (just a check and copies directly link to uf2 in clipboard<br />
- Force Bootsel<br />
<br />
[[File:picotuner_driverinstall.png|400px]]<br />
<br />
Once PicoTuner drivers are properly installed on Windows 10, they show up in Device Manager as shown below:<br />
<br />
[[File:PicoTuner in Device Manager.JPG|200px]]<br />
<br />
==Portsdown==<br />
<br />
Version 202403110 onwards of the Portsdown 4 receiver is compatible with PicoTuner but can only display one channel.<br />
<br />
See the following pages on using the Portsdown receiver.<br />
<br />
[[Portsdown_4#Portsdown_4_receive_capabilities:|https://wiki.batc.org.uk/Portsdown_4#Portsdown_4_receive_capabilities:]] <br />
<br />
[[DVB-S/S2 Reception|https://wiki.batc.org.uk/DVB-S/S2_Reception]]<br />
<br />
==Ryde==<br />
<br />
Version 202403220 onwards of the Ryde Receiver is compatible with PicoTuner but can only display one channel.<br />
<br />
==Minitiouner software - NOT compatible==<br />
<br />
Current versions of the MiniTiouner PC software '''WILL NOT''' work with PicoTuner. As F6DZP is no longer updating Minitioune it will probably never be compatible.<br />
<br />
=PicoTuner hardware=<br />
<br />
Mike G0MJW has designed a PCB which will host the Serit NIM and Pico board. The Pico can either be a standard board or the WIZnet W5100S-EVB-Pico or W5500-EVB-Pico, which are basically a Pico with an integrated Ethernet interface.<br />
<br />
[[File:Picotuner Mk1.png|400px]]<br />
<br />
Full details are available here [[PicoTuner Hardware]]<br />
<br />
=Surface mount PicoTuner adaptor for the MiniTiouner V2 PCB=<br />
<br />
Whilst the PicoTuner was designed for use in a new tuner design it can also be retrofitted to the BATC V2 Minitiouner and similar designs providing their FTDI modules are fitted in sockets. <br />
<br />
Full details are available here: [[Surface mount PicoTuner adaptor for the MiniTiouner V2 PCB]]<br />
<br />
= Programming the Pico =<br />
<br />
T. <br />
<br />
1. Locate the latest compiled firmware file 'muntjac4_pico-1v**.uf2' which will be found here https://github.com/davecrump/portsdown4/blob/master/src/muntjac/muntjac4_pico-1v0b.uf2 and save it to your desktop. <br />
<br />
2. Hold down the BT button (the one nearest the output sockets) on the Muntjac while connecting it to your PC using its USB port. The Pico Muntjac appear as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The Muntjac will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB device.<br />
<br />
4. Disconnect the Muntjac from the PC and connect it to the Portsdown. Make sure that the Muntjac is selected as the Output Device and then Select M2, Info. The Muntjac firmware version will be displayed along with the Muntjac Flash ID.<br />
<br />
= Ethernet Interface for PicoTuner =<br />
<br />
It is possible to fit the PicoTuner with a wired Ethernet interface. This integrates an Ethernet chip with a Pico processor chip. It enables the PicoTuner to be used as a 2 receiver WinterHill, or it can be used with OpenTuner software, version 0.B or later. <br />
<br />
Status information is available over the USB serial port, but command input and transport stream output is possible only over the Ethernet connection.<br />
<br />
Full details can be found here [[PicoTuner Ethernet Interface]].<br />
<br />
= Fault-finding =<br />
<br />
When used with the Portsdown, if the message "Resetting USB Bus" appears, it generally means that power has not been applied to the Tuner. To recover from this situation, '''you MUST disconnect the USB connection, pause 5 seconds, reconnect the USB connection and then apply power''' to the tuner. Simply applying power does not solve the problem.<br />
<br />
Subsequent "Waiting for Tuner to Respond" messages can normally be cured by disconnecting the USB connection and reconnecting after 5 seconds.<br />
<br />
You can check if the USB connection is working by going to Menu 2, File Menu, List USB Devices. The BATC PicoTuner should appear in the list.</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=PicoTuner&diff=12314PicoTuner2026-04-20T10:49:39Z<p>G8GKQ: /* Programming the Pico */</p>
<hr />
<div>PicoTuner is a USB tuner PCB for DATV based around the Serit 4334 NIM using the RpiPico as the USB interface.<br />
<br />
The main reason for the development is to use the £5 Raspberry Pi Pico in place of the £32 FTDI USB interface on the MiniTiouner PCB. Using the Pico interface also enables 2 channels to be decoded and displayed at the same time.<br />
<br />
The PicoTuner replaces the MiniTiouner Mk2 PCB for all new builds, however limited stock of the MiniTiouner PCB and FTDI module will be held in the BATC shop for those who wish to continue to use the MiniTiouner software which is NOT compatible with PicoTuner.<br />
<br />
=Receivers compatible with PicoTuner=<br />
<br />
==OpenTuner==<br />
<br />
Version V0.9 onwards of OpenTuner by Tom ZR6TG is compatible with PicoTuner and can display 2 channels simultaneously.<br />
<br />
You will need to install the usb drivers to be able to use it with OpenTuner. Details can be found here https://www.zr6tg.co.za/2024/02/11/picotuner-an-experimental-dual-ts-alternative/<br />
<br />
Alternatively, ZR6TG has developed a simple test app that will install the windows drivers for PicoTuner. It is at beta version but available from here: https://www.dropbox.com/scl/fi/3ziiiq71hretd2yzaou8f/picotuner_driver_test_app.zip?rlkey=gl4xsxddxprxfvjjydebvez5y&dl=0<br />
<br />
- You can detect and check the drivers<br />
- Install the drivers (required admin privs - right click and run as administrator)<br />
- Check PicoTuner Version<br />
- Check github for latest version (just a check and copies directly link to uf2 in clipboard<br />
- Force Bootsel<br />
<br />
[[File:picotuner_driverinstall.png|400px]]<br />
<br />
Once PicoTuner drivers are properly installed on Windows 10, they show up in Device Manager as shown below:<br />
<br />
[[File:PicoTuner in Device Manager.JPG|200px]]<br />
<br />
==Portsdown==<br />
<br />
Version 202403110 onwards of the Portsdown 4 receiver is compatible with PicoTuner but can only display one channel.<br />
<br />
See the following pages on using the Portsdown receiver.<br />
<br />
[[Portsdown_4#Portsdown_4_receive_capabilities:|https://wiki.batc.org.uk/Portsdown_4#Portsdown_4_receive_capabilities:]] <br />
<br />
[[DVB-S/S2 Reception|https://wiki.batc.org.uk/DVB-S/S2_Reception]]<br />
<br />
==Ryde==<br />
<br />
Version 202403220 onwards of the Ryde Receiver is compatible with PicoTuner but can only display one channel.<br />
<br />
==Minitiouner software - NOT compatible==<br />
<br />
Current versions of the MiniTiouner PC software '''WILL NOT''' work with PicoTuner. As F6DZP is no longer updating Minitioune it will probably never be compatible.<br />
<br />
=PicoTuner hardware=<br />
<br />
Mike G0MJW has designed a PCB which will host the Serit NIM and Pico board. The Pico can either be a standard board or the WIZnet W5100S-EVB-Pico or W5500-EVB-Pico, which are basically a Pico with an integrated Ethernet interface.<br />
<br />
[[File:Picotuner Mk1.png|400px]]<br />
<br />
Full details are available here [[PicoTuner Hardware]]<br />
<br />
=Surface mount PicoTuner adaptor for the MiniTiouner V2 PCB=<br />
<br />
Whilst the PicoTuner was designed for use in a new tuner design it can also be retrofitted to the BATC V2 Minitiouner and similar designs providing their FTDI modules are fitted in sockets. <br />
<br />
Full details are available here: [[Surface mount PicoTuner adaptor for the MiniTiouner V2 PCB]]<br />
<br />
= Programming the Pico =<br />
<br />
This can be done either before or after the Pico has been fitted to the PCB, it makes no difference. Updating to a new firmware version is done the same way. <br />
<br />
1. Locate the latest compiled firmware file 'muntjac4_pico-1v**.uf2' which will be found here https://github.com/davecrump/portsdown4/blob/master/src/muntjac/muntjac4_pico-1v0b.uf2 and save it to your desktop. <br />
<br />
2. Hold down the BT button (the one nearest the output sockets) on the Muntjac while connecting it to your PC using its USB port. The Pico Muntjac appear as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The Muntjac will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB device.<br />
<br />
4. Disconnect the Muntjac from the PC and connect it to the Portsdown. Make sure that the Muntjac is selected as the Output Device and then Select M2, Info. The Muntjac firmware version will be displayed along with the Muntjac Flash ID.<br />
<br />
= Ethernet Interface for PicoTuner =<br />
<br />
It is possible to fit the PicoTuner with a wired Ethernet interface. This integrates an Ethernet chip with a Pico processor chip. It enables the PicoTuner to be used as a 2 receiver WinterHill, or it can be used with OpenTuner software, version 0.B or later. <br />
<br />
Status information is available over the USB serial port, but command input and transport stream output is possible only over the Ethernet connection.<br />
<br />
Full details can be found here [[PicoTuner Ethernet Interface]].<br />
<br />
= Fault-finding =<br />
<br />
When used with the Portsdown, if the message "Resetting USB Bus" appears, it generally means that power has not been applied to the Tuner. To recover from this situation, '''you MUST disconnect the USB connection, pause 5 seconds, reconnect the USB connection and then apply power''' to the tuner. Simply applying power does not solve the problem.<br />
<br />
Subsequent "Waiting for Tuner to Respond" messages can normally be cured by disconnecting the USB connection and reconnecting after 5 seconds.<br />
<br />
You can check if the USB connection is working by going to Menu 2, File Menu, List USB Devices. The BATC PicoTuner should appear in the list.</div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12313The Muntjac SDR2026-04-20T10:44:48Z<p>G8GKQ: /* Shoulders at Various Power Settings */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. If you would like your calibration file added to this library, please e-mail it to G8GKQ. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Shoulders at Various Power Settings===<br />
<br />
The plots below show the effect of the power setting on the level of the shoulders at SR333. Shoulders are generally lower on 437MHz for the same power setting. <br />
<br />
[[File:Snap80a.jpg|400px]] [[File:Snap76b.jpg|400px]]<br />
<br />
[[File:Snap75c.jpg|400px]] [[File:Snap77d.jpg|400px]]<br />
<br />
The rising levels at the edges of the plots are an artefact of the Pluto band viewer, as shown by the PWR8 plot in a 10MHz bandwidth.<br />
<br />
[[File:Snap78e.jpg|400px]]<br />
<br />
===Programming the Microcontroller on the Muntjac===<br />
<br />
Muntjacs are provided pre-programmed by the BATC Shop, but this is the procedure to load a firmware update if required. <br />
<br />
1. Locate the latest compiled firmware file 'PicoTuner_vxxx.uf2' which will be found here https://github.com/g4eml/PicoTuner/releases and save it to your desktop. <br />
<br />
2. Hold down the BOOTSEL button on the Pico while connecting it to your PC using its micro USB port. The Pico should appear as a USB disk drive on your PC.<br />
<br />
3. Copy the .uf2 file onto the USB drive. The Pico will recognise the file and immediately update its firmware, reboot and the PC should recognise a new USB device.<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem. However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12276The Muntjac SDR2026-04-16T13:57:15Z<p>G8GKQ: /* IQ Calibration */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. If you would like your calibration file added to this library, please e-mail it to G8GKQ. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12275The Muntjac SDR2026-04-16T13:56:26Z<p>G8GKQ: /* IQ Calibration */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may have been calibrated before sale. The calibration files for these are included in the latest Portsdown software, and the correct file is loaded when the Muntjac is registered using the procedure above. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. The library of files is in the folder /home/pi/rpidatv/src/muntjac. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo. If you would like your calibration file added to this library, please e-mail it to G8GKQ.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12274The Muntjac SDR2026-04-16T13:52:55Z<p>G8GKQ: /* Using Muntjac with the Portsdown 4 */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", select "Output to" and then "Muntjac" again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. This procedure also copies any published calibration file (see below) to the correct folder for use <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may be sold with a calibration file, which will be available for download and incorporation into the Portsdown software. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12273The Muntjac SDR2026-04-16T13:32:12Z<p>G8GKQ: /* Using Muntjac with the Portsdown 4 */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required. The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", simply press the "Muntjac" button again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may be sold with a calibration file, which will be available for download and incorporation into the Portsdown software. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12272The Muntjac SDR2026-04-16T13:30:14Z<p>G8GKQ: /* Preparing for Use */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D <br />
<br />
[[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required.<br />
<br />
The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", simply press the "Muntjac" button again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may be sold with a calibration file, which will be available for download and incorporation into the Portsdown software. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12271The Muntjac SDR2026-04-16T13:29:43Z<p>G8GKQ: /* Preparing for Use */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D [[File:SMA Connector.png|200px]]<br />
<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required.<br />
<br />
The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", simply press the "Muntjac" button again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may be sold with a calibration file, which will be available for download and incorporation into the Portsdown software. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12270The Muntjac SDR2026-04-16T13:25:48Z<p>G8GKQ: /* IQ Calibration */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D [[File:SMA Connector.png|200px]]<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required.<br />
<br />
The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", simply press the "Muntjac" button again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may be sold with a calibration file, which will be available for download and incorporation into the Portsdown software. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
The Muntjac calibration file has a file name of the format E46214B063533828.mjo where the E number is the flash ID of the RP2040 chip. A file of the correct format with the correct name in the /home/pi/rpidatv/bin/ folder is automatically read by the Muntjac driver and the settings applied. An example file can be found at https://github.com/davecrump/portsdown4/blob/master/src/muntjac/E46214B063533828.mjo<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12269The Muntjac SDR2026-04-16T13:20:44Z<p>G8GKQ: /* IQ Calibration */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D [[File:SMA Connector.png|200px]]<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required.<br />
<br />
The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", simply press the "Muntjac" button again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. This causes a reduction in received MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
Some Muntjacs may be sold with a calibration file, which will be available for download and incorporation into the Portsdown software. However, some may not have been factory calibrated (although they will have been tested). They will function perfectly well for DATV without this file. A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12268The Muntjac SDR2026-04-16T13:17:53Z<p>G8GKQ: /* Using Muntjac with the Portsdown 4 */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this:<br />
<br />
https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D [[File:SMA Connector.png|200px]]<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required.<br />
<br />
The Muntjac drivers are included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot. After connecting a "new" Muntjac to your Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", simply press the "Muntjac" button again. A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above. Then connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900 MHz) and the high band output is used for 2400 MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. <br />
<br />
This causes a reduction in MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. <br />
<br />
It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression. <br />
<br />
The required register values vary with the power setting, although not very much within each group of four power settings, so calibration values are only required for power settings 0, 4, 8, 12, 16, 20, 24, 28. <br />
<br />
The plan is to generate a calibration file at the factory for each Muntjac, which will be available for download and incorporation into the Portsdown software.<br />
<br />
A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12263The Muntjac SDR2026-04-14T18:39:39Z<p>G8GKQ: /* Preparing for Use */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this: https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D [[File:SMA Connector.png|200px]]<br />
Cheaper suitable connectors are available on eBay.<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required.<br />
<br />
The Muntjac is included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot.<br />
<br />
After connecting the Muntjac to the Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", change it to something else and then back to "Muntjac".<br />
<br />
A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above.<br />
<br />
Connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900MHz) and the high band output is used for 2400MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. <br />
<br />
This causes a reduction in MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. <br />
<br />
It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression.<br />
<br />
The plan is to generate a calibration file at the factory for each Muntjac, which will be available for download and incorporation into the Portsdown software.<br />
<br />
A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=The_Muntjac_SDR&diff=12262The Muntjac SDR2026-04-14T18:38:48Z<p>G8GKQ: /* Preparing for Use */</p>
<hr />
<div>The Muntjac SDR was designed by Brian G4EWJ based on the same dual-band AT86RF215 RF chip as the commercially available CaribouLite SDR. <br />
<br />
It is a transmit-only SDR for DVB-S2 DATV on 13cm (QO-100) and 70cm, which uses an RP2040 micro-controller, as used on the Raspberry Pi Pico, to provide a USB interface to the Portsdown 4.<br />
<br />
When operating from the command line, the same transmission may be made on both bands simultaneously. <br />
<br />
The 75 x 30mm board comes without SMA connectors, so that it can optionally be wired into a system, for maximum flexibility. Long thread SMA types are recommended. <br />
<br />
The optional user-fitted ADE-30+ mixer is shown, which can be used for experiments on other bands. DATV is generated on the high band and mixed with the harmonic of a carrier on the low band. In theory, output on all bands from 1.8MHz to 3.4GHz is possible, but this is subject to further investigation.<br />
<br />
Muntjac-4 was meant to be intermediate development version, but it is working well enough to make it available as part of an extended beta trial. Some configuration in Linux may be necessary, so if you don't consider yourself to be an 'early-adopter' it may be worth waiting until it has matured.<br />
<br />
<br />
[[File:cqtvmj25-1a.jpg|400px]] [[File:cqtvmj25-2a.jpg|400px]]<br />
<br />
&nbsp;<br />
&nbsp;<br />
<br />
===Specifications===<br />
<br />
The Muntjac SDR only operates with output frequencies in the following ranges: 390 - 510 MHz, 779- 1020 MHz and 2400 - 2483 MHz. Individual examples may operate slightly outside these frequency ranges, but not significantly. For our use, this means that the Muntjac can only be used directly on 70 cm and the QO-100 uplink. Clearly, with external transverters it could be used on any band.<br />
<br />
When used with the Portsdown 4, the Muntjac will transmit DVB-S2 QPSK with symbol rates of 125, 250, 333.333, 500 and 1000 kS. It will also transmit DVB-S2 8PSK with symbol rates of 125, 250, 333.333 and 500 kS. DVB-S is not supported.<br />
<br />
Transmit data is sent to the AT chip at 128M bits/s on an LVDS bus. This is 4M x 13bit IQ samples/s, with 4 times oversampling, which limits the symbol rate to 1000k symbols/s.<br />
<br />
The output power setting parameter (gain) range of the AT86RF215 is 0-31, with each step being nominally 1dB and power zero being -15dBm. <br />
<br />
When selecting power on the Portsdown screen, this parameter is restricted to a maximum of 20, as the shoulders on the output increase rapidly above this.<br />
<br />
At power setting 20, shoulders on the output are at least 30dB down and are further down at lower output powers. Approximate output power is shown in the table below.<br />
<br />
{| class="wikitable"<br />
|+ Muntjac Performance<br />
|-<br />
! Gain Setting !! 437 MHz O/P !! 437 MHz Shoulders !! 2409 MHz O/P !! 2409 MHz Shoulders<br />
|-<br />
| 20 || +5.6 dBm || -34 dB || +4.1 dBm || -30 dB<br />
|-<br />
| 19 || +4.8 dBm || || +3.7 dBm || <br />
|-<br />
| 18 || +4.0 dBm || || +2.8 dBm || <br />
|-<br />
| 17 || +3.0 dBm || || +2.1 dBm || <br />
|-<br />
| 16 || +2.1 dBm || || +1.2 dBm || <br />
|-<br />
| 15 || +0.8 dBm || -40 dB || +0.5 dBm || -40 dB<br />
|-<br />
| 14 || +0.1 dBm || || -0.5 dBm || <br />
|-<br />
| 13 || -0.9 dBm || || -1.4 dBm || <br />
|-<br />
| 12 || -1.9 dBm || || -2.5 dBm || <br />
|-<br />
| 11 || -2.6 dBm || || -3.3 dBm || <br />
|-<br />
| 10 || -3.6 dBm || -50 dB || -4.4 dBm || -43 dB<br />
|-<br />
| 9 || -4.7 dBm || || -5.3 dBm || <br />
|-<br />
| 8 || -5.7 dBm || || -6.3 dBm || <br />
|-<br />
| 7 || -6.4 dBm || || -7.3 dBm || <br />
|-<br />
| 6 || -7.4 dBm || || -8.3 dBm || <br />
|-<br />
| 5 || -8.4 dBm || < -50 dB || -9.3 dBm || < -45 dB<br />
|-<br />
| 4 || -9.4 dBm || || -10.3 dBm || <br />
|-<br />
| 3 || -10.2 dBm || || -11.1 dBm || <br />
|-<br />
| 2 || -11.2 dBm || || -12.1 dBm || <br />
|-<br />
| 1 || -12.2 dBm || || -13.1 dBm || <br />
|-<br />
| 0 || -13.2 dBm || < -50 dB || -14.1 dBm || < -45 dB<br />
|}<br />
<br />
The output power at 900 MHz is typically 3 dB less than that at 437 MHz.<br />
<br />
===Preparing for Use===<br />
<br />
The Muntjac is supplied as a kit with the final assembly step of soldering the output connectors to the PCB required for completion. The SMA connectors are not supplied. If the SDR is to be mounted in a box (it does fit a small die-cast box) right-angle SMAs with long shafts should be used to allow sufficient clearance between the SMA plug and the box. An suitable example connector is this: https://www.mouser.co.uk/ProductDetail/TE-Connectivity-Linx-Technologies/CONSMA002-L-G?qs=vLWxofP3U2xfxfFnu8BdmA%3D%3D [[File:SMA Connector.png|200px]]<br />
<br />
An example of the Muntjac mounted in a box (with short SMA Conectors) is shown here.<br />
<br />
[[File:Muntjac boxed.jpg|400px]]<br />
<br />
===Another Boxing Idea===<br />
<br />
As Muntjac-4 was meant to be an intermediate development version, not much thought was given to fitting it into a box. <br />
<br />
The Hammond 1550P can be used by cutting slots into the top edges of the box and dropping in the Muntjac-4 board vertically. <br />
<br />
The 1550P is about £6 in bare metal and about double that as the 1550PBK with a black finish.<br />
<br />
[[File:Mj1550p.png|400px]]<br />
<br />
===Using Muntjac with the Portsdown 4===<br />
<br />
The Muntjac connects to the Portsdown by USB. No other power supply is required.<br />
<br />
The Muntjac is included in the latest Portsdown 4 software, so make sure that your Portsdown is up to date using Menu 3 and 'Check for Update'. If the Muntjac is connected to the Portsdown, disconnect it before updating.<br />
<br />
The first time you use each Muntjac device, it needs to be registered so that the Raspberry Pi recognises it at the next reboot.<br />
<br />
After connecting the Muntjac to the Portsdown 4, select "Output to" and then "Muntjac". If "Output to" is already set to "Muntjac", change it to something else and then back to "Muntjac".<br />
<br />
A message will pop up saying "System will reboot now to register new Muntjac. Touch screen to continue". Touch the screen, and after the reboot, your Muntjac is ready for use. <br />
<br />
You will not need to repeat this process unless you connect a different Muntjac, or you use a different Portsdown.<br />
<br />
Next, set the Muntjac gain with reference to the table above.<br />
<br />
Connect the correct output to your transmit amplifier; the low band output is used for 437 MHz (and 900MHz) and the high band output is used for 2400MHz. The high band output is to the north of the "Muntjac-4" legend.<br />
<br />
Within the limitations above, the Muntjac behaves similarly to a LimeSDR Mini.<br />
<br />
===LEDs===<br />
<br />
There is a main LED near the buttons and an LED near each SMA socket.<br />
<br />
The main LED blinks 'HI' in morse (.... ..) at power up. This is for software version 1v0b. Later versions will blink 'MJ' and the last letter of the software version.<br />
<br />
The LED near each SMA socket is normally off and lights when that band (low or high) is in use.<br />
<br />
The main LED is normally on and blinks off 1 / 2 / 3 times depending on whether low / high / both bands are active.<br />
<br />
If the main LED blinks quickly and continuously, this indicates a Muntjac error and it is waiting for the USB data feed from the Portsdown to be stopped.<br />
<br />
The main LED output is also available on the 12 pin J4 socket position, for mounting on a box. Pin 11 is ground and pin 12 is for the +ve end of an LED, through a suitable resistor.<br />
<br />
Pin 1 of J4 is the square one and odd numbered pins are along the edge of the board.<br />
<br />
===First Transmission===<br />
<br />
If you're not familiar with the Portsdown, set the lines starting 'Modulation', 'Freq' and 'EasyCap' as shown and enter your callsign via 'Menu 3' and 'Set Call, Loc & PIDs'.<br />
<br />
[[File:Pdmainscreen1.png|400px]]<br />
<br />
Press 'TX' and after a second or two, the Muntjac main LED near the buttons will start double blinking off and the LED near the high band SMA will light steady.<br />
<br />
===Monitoring Muntjac Driver Operation===<br />
<br />
The Muntjac driver (muntjacsdr_dvb) on the Portsdown outputs a log to a UDP network port. To see this, log into the Portsdown with ssh and type:<br />
<br />
'''nc -kluv 9979'''<br />
<br />
===Lack of Calibration Spikes===<br />
<br />
The AT86RF215 chip does a self calibration before transmitting, but it does this with its final amplifier turned off, so it is not necessary to isolate the output for a number of seconds as with the Pluto and Lime. This is the observation so far, but it's early days for the project, so verify this for yourself.<br />
<br />
===IQ Calibration===<br />
<br />
Poor IQ balance in an SDR can cause a carrier (the local oscillator) to be transmitted at the centre frequency of a DATV transmission. <br />
<br />
This causes a reduction in MER. The reduction is most noticeable at high MER, but it will not affect reception, because the MER is already high. <br />
<br />
It seems to have less effect when the MER is comparatively low, as on QO-100. It just looks wrong to see a spike in the middle of your signal.<br />
<br />
The AT86RF215 chip does an IQ balance as part of its self calibration before transmitting, but it doesn't always do the best job. Fortunately there are registers in the chip which can be adjusted to improve the local oscillator suppression.<br />
<br />
The plan is to generate a calibration file at the factory for each Muntjac, which will be available for download and incorporation into the Portsdown software.<br />
<br />
A tool is under development to enable the Muntjac calibration file to be generated by the user.<br />
<br />
===Output Filtering===<br />
<br />
The low band output must be bandpass filtered.<br />
<br />
The high band output uses a combined bandpass and notch filter balun, specially designed for the AT86RF215, so additional filtering should not be necessary. <br />
<br />
If the low band output is also active, additional filtering on the high band output may be required, to address any feedthrough from the low band output and its harmonics.<br />
<br />
https://www.johansontechnology.com/docs/796/2450FB15A050_VdAqien.pdf<br />
<br />
===Frequency Accuracy===<br />
<br />
The AT86RF215 uses an externally connected TXCO on the pcb, with a temperature stability of 0.5ppm and initial accuracy of +/- 2ppm. The 2.4GHz output should be within a few kHz of nominal.<br />
<br />
https://aker-usa.com/spec/TX21.pdf<br />
<br />
===Problems===<br />
<br />
The Muntjac may not be seen as a USB COM port when connected to a USB3 hub. The USB3 sockets on the RPi4 are not a problem.<br />
<br />
However, it will appear as a virtual USB drive for software update when connected to a USB3 hub, which is odd. <br />
<br />
<!--<br />
<br />
=== Programming the Muntjac===<br />
<br />
Muntjac SDRs are supplied with the correct program loaded in the RP2040. Should this need to be re-written, download this Zip file on a Windows PC and unzip it to get a .uf2 file [[:File:muntjac4-0v1c.zip]].<br />
<br />
The current development release of Portsdown 4 (202601020) requires a later version of the RP2040 program: [[:File:muntjac4_pico-1v0b.zip]]. <br />
<br />
Press the BT (boot) button on the Muntjac whilst connecting it to the Windows PC by USB. A new disk drive labelled RPI-RP2 should appear on the PC; you can then release the button. Copy the .uf2 file into the RPI-RP2 drive. Once the file has copied, the disk drive will unmount. Disconnect the Muntjac from the Windows PC; it is ready for use with the Portsdown.<br />
<br />
--></div>G8GKQhttps://wiki.batc.org.uk/index.php?title=File:SMA_Connector.png&diff=12261File:SMA Connector.png2026-04-14T18:38:37Z<p>G8GKQ: File uploaded with MsUpload</p>
<hr />
<div>File uploaded with MsUpload</div>G8GKQ