Scripting - agree on that 
Can be wise to keep an option of crossband full duplex,
not just TX/RX in semiduplex. After all Lime is capable for full duplex…
73
Djani
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@F4EXB – Hi Edouard,
In the weekend I have installed the Windows Version of SDRAngel 3.7.3 and tested it with LimeSDR and Adalm Pluto. I like your sampling devices window. First it gives a small shock that there is so much info in a small window, but then it is very nice to have all sampling rates and the LImeSDR frequencies with and without NCO available at a glance.
LImeSDR RX and TX and Adalm Pluto RX seems to work OK for me. For the Adalm Pluto TX I have the impression that there is no sideband rejection. Both sidebands are transmitted even if only one is intended. I noticed that in the LImeSDR sampling device windows the values for the LP filter cut-off frequency are really two times the LP cut-off frequency. This also explains that, as noticed by @brendanthebig and @martywittrock, values of 60 MHz work better than 30 MHz.
The Tone modulation in the SSB modulator is also a nice feature for quick testing. Especially the possibility to switch between single and dual tone by toggling between SSB and DSB. However the dual tones caused clipping in both LimeSDR and Adalm Pluto . Could you reduce the level of the dual tones by 6 dB instead of 3 dB? (PEP of dual tone increases by 6 dB)
I think it is really nice to have the possibility to compare the performance of LimeSDR and Adalm Pluto in 1 SDR program and am looking forward for further developments.
Best Regards, Cornie
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@F4EXB - Edouard,
Actually, if this could be made as a separate window much like the sampling window, etc. to contain the bandswitching, PTT opition (giving a nod to @9a4db suggestion to leave it as full duplex), and have 2 IOs to control of the PA (inline/offline, and antenna switch) that would be ideal. It would also be ideal that if there’s a change made to select a band (160m, 80/75m, 60m, 40m, 30m, 20m, 17m, 15m, 12m, 10m, 6m, 2m, 70cm) that it would also configure the frequency selection to that band - that’s not a hard requirement so much as it’s a ‘nice to have’. You’ll have to work with @andrewback to obtain the GPIO board for the LimeSDR, but I can assure you that if this board was added to SDRAngel’s capabilities many Hams would spring for that GPIO board because it solves A LOT of band switching and antenna switching issues. Putting it on a seperate menu also eliminates the need for it to be mixed into already existent windows.
@andrewback: Appears Edouard is interested in this GPIO board for SDRAngel. Can you work with him to get him a GPIO board for his LimeSDR? Thanks in advance for working that…! 
73 de Marty, KN0CK
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Hello Cornie,
I did not notice the clipping youŕe talking about at least on the Pluto. On the Pluto however both sidebands are transmitted in SSB mode and that does not occur with the HackRF so this is not due to the generated baseband signal. I have yet to try with the Lime. Perhaps the Pluto does not work in SSB around the zero frequency I ahve to try shifting the center frequency in baseband as well.
Edit: it seems I/Q balance on Pluto Tx is really bad. Shifting a single carrier with an AM modulator in baseband results in an image carrier of equal amplitude around the center frequency. Maybe there is a calibration needed at some point but the documentation is so poor that I don’t know how to code this.
Edit2: eventually I could run into clipping in DSB as well which appears in baseband so this one is on software side.
Edit3: Lime works fine
Best regards, Edouard.
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I’m thinking the 8 IO’s on the GPIO board may not be enough if we want to do band filter switching. Might need to use a 4 to 16 decoder on 4 of the IO pins so as to be able to select 1 of up to 16 filters. That should leave enough pins for PTT and RF relay / PA / PRE-AMP control…Looking forward to see how this all goes.
Regards,
Brendan,
VK3WWB.
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There are chips like these:
http://www.newark.com/search?st=74HC595
Which you can even address, to greatly expand the IO.
I was thinking of a 74HC154. 4 bits in to get 1 of 16 outputs…
Hallo Eduard,
The fact that the image has equal amplitude makes me think that it’s not a calibration problem. Most I/Q demodulator provide a reduced but still existing image rejection also without calibration
As far as I know simple errors like I or Q not written, I or Q =0, I=Q could cause equal amplitudes.
I totally agree with your point about bad documentation. Still waiting with many others for some proper documentation about LimeSDR calibration strategy.
With edit3 do you mean you have seen no clipping on the LimeSDR? As far as I remember I saw some clipping. I can make some screenshots if you want.
Best regards, Cornie
Hello,
the I/Q problem is with the Pluto only and bad documentation was referencing the libiio / PlutoSDR combination. LimeSDR documentation can be improved as well in particular on calibration procedure but it is not as bad as Pluto’s. There even the example code is wrong. I agree that there must be a more severe error than just calibration to explain the equal images around zero IF. It probably has something to do with the way the I/Q data is sent to Pluto because the baseband spectrum which is monitored in the spectrum window is correct. Again with the way this is documented you can only make guesses on how the data format should be plus the way the data is sent or received is very different from other SDR platforms and quite weird actually.
For the DSB question there is probably an issue as well and I stil have to make up a scenario that exhibits the problem systematically.
Best regards, Edouard.
I’ve been playing with the latest sdrangel on both ubuntu and win7 x64. The BFM decoder has a problem in that it won’t shift the frequency. Has anybody else had this problem ?
I have also noticed that changing the RF and AF bandwidths in the BFM decoder is not working.
I have tried to upload a screenshot but am not having any luck…Any chance someone can enlighten me on the procedure to add images to my replies ???
Regards,
Brendan,
VK3WWB
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After further testing, it seems that the RF bandwidth is working but not the AF bandwidth. I will investigate further and report back soon.
@F4EXB, FYI I have updated the FW/GW on my LimeSDR so I am not sure if the problems I am having are due to the update or sdrangel itself. I will try to downgrade the FW/GW and see how it goes. I’ll post my results soon.
@andrewback, is it possible to downgrade the firmware/gateware. If so, can you direct me to where I can download older versions please.
Regards,
Brendan,
VK3WWB.
Hello Brendan,
I have changed the way the GUI and the core demodulator communicate so there may well be a problem. I will check myself.
Best regards, Edouard.
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Thanks for the prompt reply Edouard.
The sound quality of the BFM decoder is quite poor for me at the moment. I suspect this is due to DC offset.
The good thing with the Lime is that you can use the NCO to shift away the DC.
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I’ll give that a try and get back to you in a couple of minutes with my results.
I had the problem that if I set the bandwidth over 20MS/s the frequency scale increased but the actual bandwidth and the data rate remains the same (20MS/S and 60MB/s). In an older version I was able to get at least 30MS/s ruining quite fine.