GNU Radio support status

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airprakken
Posts: 1
Joined: Mon Apr 18, 2016 8:44 pm

GNU Radio support status

Post by airprakken » Fri Apr 29, 2016 10:40 pm

Frustrated here. I am working in Python on Linux with SDRplay and GNU Radio. I have tried the direct osmo support interface and found problems which appeared to still require the patches discussed elsewhere. I saw the recommendations to use SoapySDR instead and installed that and removed the direct osmo support. I also saw that Soapy people recommended going through the new osmosdr.source() support and am using that.

So, I believe I am doing this: Python -> osmosdr.source() -> SoapySDR -> SDRPlay binary library

Issue: I have some pretty cool stuff running (i.e. no configuration issues) but the low signal level performance is MUCH worse than SDR Console listening to the same signals on the same SDRplay and the same antenna antenna. I have tried many times to understand exactly how the RF (and other) gain is set through this interface but I have never found definitive documentation. I am reasonably certain that this is the source of my poor low signal performance and have tried for many hours to find solutions and real documentation. Pretty soon I either need to solve these gain setting issues or move on to a different device.

Q1: Does this interface I am using support all SDRplay gain controls as discussed in places like this: http://sdrplay.com/docs/SDRplay_AGC_technote_r2p0.pdf
or not?

Q2: If so, what are the calls to make ?

Q3: If not, when will that support be coming? Ever ?

A few notes. I can provide more:

If I use just set_gain() the STDOUT messages seem to show that some level below me is playing with several different gain levels:
mir_sdr_SetGr: GR->32[8,24,0,0] gRset->0x208 DCCALmode=1 DCCALspd=1 GrToggle->1

If I attempt to also use set_if_gain() I get initial results different at initialization but as soon as I call set_gain() again it all appears to drop the if setting.

Config:
i7-5820K DDR4 based system (X99)
Linux CentOS 7 fully updated.
Python 2.7.5
GNU Radio 3.7.9.1 compiled from source
SoapySDR compiled from source: #define SOAPY_SDR_ABI_VERSION "0.5-1"
SoapySDRPlay
SDRplay_RSP_MiricsAPI-1.9.4.run
Last edited by airprakken on Thu Jan 01, 1970 12:00 am, edited 0 times in total.
Reason: No reason

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