DATV Equipment Shopping List

This page describes a number of equipment lists that enable a progressive introduction to DATV without necessarily buying everything at once. The Portsdown hardware is described in more detail here: https://wiki.batc.org.uk/Portsdown_hardware .

1. Domestic Satellite Receiver. Receive only

A domestic satellite receiver (not a Sky box) may receive amateur DATV transmissions in the 23 cm band. You should check that the receiver will accept symbol rates down to 1MS, and you will need to connect a suitable preamp and aerial. Be careful as there will by 13-18V on the satellite tuner's aerial connector. Note that domestic satellite tuners cannot receive RB-TV transmissions with the lower symbol rates of 500KS, 333KS or 125KS.

2. MiniTiouner. Receive only

The MiniTiouner [[1]] is the recommended equipment to receive amateur DATV transmissions. The MiniTiouner connects to a PC, and with suitable aerials and preamps, can receive amateur DATV transmissions at symbol rates from 125KS up to 8MS on the 146, 437, 1255 and 2400 MHz bands. It is only available in partial kit form. The BATC shop https://batc.org.uk/shop/minitiouner sells the following parts:

Serit FTS4334L tuner

MiniTiouner version 2 blank PCB

FT2232H USB module

1 volt regulator

The other parts required can be obtained from RS or Farnell and are listed here [[2]].

3. Portsdown Raspberry Pi Transmit Cross-shack to MiniTiouner ONLY

A Raspberry Pi version 3 computer can be programmed to transmit RB-TV pictures across the shack to a MiniTiouner without any additional hardware. This is known as "Ugly" (or QPSKRF) mode and the spectrum is not clean enough to be amplified or transmitted from an external aerial. Note that the maximum symbol rate is 333KS so this signal cannot be decoded by a domestic satellite receiver; only a MiniTiouner is suitable. This set-up requires:

Raspberry Pi 3 Computer and power supply

SD Card (available from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-pre-programmed-sd-card/)

MiniTiouner and PC as described in 2 above

4. Portsdown Transmit Cross-shack and local to MiniTiouner or Domestic Sat RX

To transmit DATV signals that can be received on a domestic satellite receiver and are fit for external transmission, a local oscillator and filter-modulator board need to be added. The local oscillator needs to generate about -2 dBm on the desired transmission frequency (between 70 and 2410 MHz); the recommended local oscillator is a synthesizer based on the ADF4351 IC and is available from eBay. The filter-modulator can be bought ready-built from the BATC shop, or the just the PCB can be purchased and the components purchased from DigiKey for home assembly. A GPIO break-out card and header connector makes wiring up the modules a lot easier. This set-up will generate over 2 mW of DATV on the chosen frequency:

Raspberry Pi 3 Computer and power supply

SD Card (available from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-pre-programmed-sd-card/)

ADF4351 Local Oscillator (from eBay)

Filter modulator V2 ready built PCB (from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-assembled-filter-modulator-board/)

GPIO breakout board (from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-gpio-breakout-board-blank-pcb)

Header Connector (from ModMyPi: https://www.modmypi.com/raspberry-pi/gpio-and-breadboarding/40-pin-gpio-connectors/40-pin-extra-tall-header-solder-version)

Domestic Sat RX or MiniTiouner and PC as described in 1 or 2 above

5. Multiband Touchscreen-controlled Portsdown Transmitter

The complete Portsdown transmitter is designed to work on up to 4 bands and be controlled by a Waveshare 3.5 inch touchscreen. Multiband operation requires that the VCO's 3rd harmonic is filtered out on the lower bands. Also, output switching and band select switching can be provided. A Raspberry Pi Camera provides a local picture source, and a Pi Camera Extension Lead kit makes it easier to use; a USB sound dongle provides a microphone input. An EasyCap allows the use of an external composite video input source. External filters and PAs are of course required and are described elsewhere on this Wiki. Here is a complete list of the major components:

Raspberry Pi 3 Computer and power supply

SD Card (available from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-pre-programmed-sd-card/)

Waveshare 3.5 inch Model A LCD touchscreen (available from Amazon https://www.amazon.co.uk/Waveshare-Raspberry-Resistive-Interface-Rapsberry-pi/dp/B00OZLG2YS )

GPIO breakout board (PCB from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-gpio-breakout-board-blank-pcb/, components from DigiKey)

Header Connector (from ModMyPi: https://www.modmypi.com/raspberry-pi/gpio-and-breadboarding/40-pin-gpio-connectors/40-pin-extra-tall-header-solder-version)

Raspberry Pi Camera

Raspberry Pi Camera extension lead kit (avalable from Tindie: https://www.tindie.com/products/freto/pi-camera-hdmi-cable-extension/ )

USB sound dongle (available from eBay)

EasyCap composite video capture dongle (available from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-easycap-video-capture-device/)

ADF4351 Local Oscillator (from eBay)

Local oscillator filter (PCB from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-filter-modulator-board-blank-pcb-2, components from DigiKey)

Filter modulator V2 ready built PCB (from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-assembled-filter-modulator-board)

RF output switch (PCB from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-rf-output-switch-blank-pcb, components from DigiKey)

4 band decode for Transmit switching (PCB from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-4-band-decode-blank-pcb, components from DigiKey)

Optional PE43703 or PE4302 Output Attenuator (from eBay)

Domestic Sat RX or MiniTiouner and PC as described in 1 or 2 above

6. Repeater Streaming from a Portsdown

The Portsdown software is capable of providing a stand-alone unattended streamer for repeaters. Although initial configuration requires a laptop or PC, once set up no such control is required. The minimum equipment required for streaming is:

Raspberry Pi 3 Computer and power supply

SD Card (available from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-pre-programmed-sd-card)

EasyCap composite video capture dongle (available from BATC Shop https://batc.org.uk/shop/portsdown-transmitter-easycap-video-capture-device)

G8GKQ 14 August 2017