Portsdown 2020 LimeSDR USB - Revision history

G8GKQ at 20:07, 6 April 2020

2020-04-06T20:07:14Z

G8GKQ at 20:06, 6 April 2020

2020-04-06T20:06:38Z

G8GKQ at 12:04, 2 April 2020

2020-04-02T12:04:48Z

G8GKQ: /* LimeSDR USB Power Output Levels */

2020-04-02T12:03:44Z

LimeSDR USB Power Output Levels

G8GKQ: /* LimeSDR USB Power Output Levels */

2020-04-02T12:01:36Z

LimeSDR USB Power Output Levels

G8GKQ: Created page with "Portsdown 2020 Software Version 202003300 (not yet released) introduces support for the LimeSDR USB. This was previously untested and, on testing, was found to suffer from in..."

2020-04-02T11:47:29Z

Created page with "Portsdown 2020 Software Version 202003300 (not yet released) introduces support for the LimeSDR USB. This was previously untested and, on testing, was found to suffer from in..."

New page

Portsdown 2020 Software Version 202003300 (not yet released) introduces support for the LimeSDR USB. This was previously untested and, on testing, was found to suffer from incorrect antenna swicthing. This is rectified in 202003300.

===Use of the LimeSDR USB===

The LimeSDR USB is power-hungry and may not operate correctly if powered from a single USB2 port. Either use a powered USB3 hub, a Y-lead to take power from 2 USB2 ports, or use external power.

The tested model of the LimeSDR USB was hardware version 4, and used firmware version 4, protocol version 1, gateware version 2, revision 22 (as reported by the Lime FW info button on the Portsdown). Note that the Lime DVB firmware cannot be used on the LimeSDR USB. The firmware on a connected LimeSDR USB can be updated by using the "U/D LNM or Lime USB" button. This simply runs "LimeUtil --update" and loads the latest available LimeSDR firmware to a connected LimeSDR USB (or LimeNET Micro - hence LNM). This will only work correctly if a valid internet connection is available.

"Lime USB" must be selected as the Output Device.

The RF Output is from TX1 Low for frequencies below 2 GHz and TX1 High for frequencies above 2 GHz.

If fitted and connected, the fan is initially set to auto, but is set to continuous during transmissions.

There is a significant calibration spike before transmission; use the delayed PTT function on GPIO pin 40 of the Raspberry Pi to ensure that your PA does not switch on until after calibration. One of the LimeUSB FPGA GPIOs has been set to switch as a secondary source of safe PTT, but this has not been tested.

===LimeSDR USB Power Output Levels===

There is significant variation in the output power available across the frequency band. The ouput power with Lime Gain set to 88 on a 333 kS DVB-S2 H264 transmission is shown below. Output was measured from TX1 Low below 2 GHz and from TX1 High above 2 GHz.

← Older revision		Revision as of 20:07, 6 April 2020
Line 1:		Line 1:
−	Portsdown ~~2020~~ Software Version 202003301 introduces support for the LimeSDR USB. This capability was previously untested and, on testing, was found to suffer from incorrect antenna switching. This is rectified in 202003301.	+	Portsdown Buster Software Version 202003301 re-introduces support for the LimeSDR USB. This capability was previously untested and, on testing, was found to suffer from incorrect antenna switching. This is rectified in 202003301.

	===Use of the LimeSDR USB===		===Use of the LimeSDR USB===

← Older revision		Revision as of 20:06, 6 April 2020
Line 1:		Line 1:
−	Portsdown 2020 Software Version ~~202003300 (not yet released)~~ introduces support for the LimeSDR USB. This capability was previously untested and, on testing, was found to suffer from incorrect antenna switching. This is rectified in ~~202003300~~.	+	Portsdown 2020 Software Version 202003301 introduces support for the LimeSDR USB. This capability was previously untested and, on testing, was found to suffer from incorrect antenna switching. This is rectified in 202003301.

	===Use of the LimeSDR USB===		===Use of the LimeSDR USB===

← Older revision		Revision as of 12:04, 2 April 2020
Line 1:		Line 1:
−	Portsdown 2020 Software Version 202003300 (not yet released) introduces support for the LimeSDR USB. This was previously untested and, on testing, was found to suffer from incorrect antenna ~~swicthing~~. This is rectified in 202003300.	+	Portsdown 2020 Software Version 202003300 (not yet released) introduces support for the LimeSDR USB. This capability was previously untested and, on testing, was found to suffer from incorrect antenna switching. This is rectified in 202003300.

	===Use of the LimeSDR USB===		===Use of the LimeSDR USB===

@@ Line 17: / Line 17: @@
 ===LimeSDR USB Power Output Levels===
-There is significant variation in the output power available across the frequency band.  The ouput power with Lime Gain set to 88 on a 333 kS DVB-S2 H264 transmission is shown below.  Output was measured from TX1 Low below 2 GHz and from TX1 High above 2 GHz.
+There is significant variation in the output power available across the frequency band.  The ouput power (dBm) with Lime Gain set to 88 on a 333 kS DVB-S2 H264 transmission is shown below.  Output was measured from TX1 Low below 2 GHz and from TX1 High above 2 GHz.
 [[File:Power Output Plot.JPG|936px]]

← Older revision		Revision as of 12:01, 2 April 2020
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	There is significant variation in the output power available across the frequency band. The ouput power with Lime Gain set to 88 on a 333 kS DVB-S2 H264 transmission is shown below. Output was measured from TX1 Low below 2 GHz and from TX1 High above 2 GHz.		There is significant variation in the output power available across the frequency band. The ouput power with Lime Gain set to 88 on a 333 kS DVB-S2 H264 transmission is shown below. Output was measured from TX1 Low below 2 GHz and from TX1 High above 2 GHz.
		+
		+	[[File:Power Output Plot.JPG\|936px]]