Hi Marcus, Two good things about the SDRplay, now that the gnuradio interface seems to be working, are:
1) Very high gain. I need about 30 dB of IF attenuation to get the levels right. 2) Very good data transfer rates. Right now I appear to be getting 100% of the 7 MHz samples delivered to a raspberry Pi 4 and/or Odroid n2. I’ve not yet fully checked the SDRPlay for short term transients. Note that the Pluto SDR has no (or at least few) short term transients in the RF. I did find the AIRSPY did have some transients that seem to be due to the device. These occur a few thousand times a day, but for shorter than 100 micro seconds. Total time on is less than a second a day. I’ll try to do another calibration test. My initial test seemed to show significant gain changes across the 7MHz band, as if I have the wrong filter selected. At one end the Tsys was too low and at the other end the Tsys was too high, with a reasonable value of about 100 K in the middle of the 1420 MHz band. Still trying to figure this out. Best regards Glen > On Nov 15, 2019, at 11:56 AM, Marcus D. Leech <patchvonbr...@gmail.com> wrote: > > On 11/15/2019 09:17 AM, Glen I Langston wrote: >> Thank for your help Chris, >> >> I have now gotten the SDRPlay connected to my telescope >> and the results are looking reasonable. >> >> My initial problems were with the sense of the gain values, which >> are actually attenuation values for the SDRPlay. >> >> It seems like the defaults are reasonable, and that probably >> the correct band pass filter is being chosen for the >> observing frequency of 1420.4 MHz. >> >> I still do not fully know what the LNA slider value does. >> >> FYI the initial interfering lines seem to have gone away after >> I got sufficiently strong signals into the SDRPlay. >> >> Best regards >> >> Glen > Glen: > > I'm keen to learn of your progress on this. I bought a couple of the > much-cheaper "clones", and I have them working, but haven't tried any > astronomy with them yet. > > Cheers > Marcus > >>> On Nov 14, 2019, at 2:57 PM, Chris Vine <vine35792...@gmail.com> wrote: >>> >>> On Thu, 14 Nov 2019 19:35:13 +0000 >>> Chris Vine <vine35792...@gmail.com> wrote: >>>> The original poster can get some information from installing soapy and >>>> doing 'SoapySDRUtil --probe'. >>> I should probably have appended what the probe tells me about my RSP1A, >>> which may or may not apply to his: >>> >>> ---------------------------------------------------- >>> -- Device identification >>> ---------------------------------------------------- >>> driver=SDRplay >>> hardware=RSP1A >>> mir_sdr_api_version=2.130000 >>> mir_sdr_hw_version=255 >>> serial=xxxxxxxxxxx >>> >>> ---------------------------------------------------- >>> -- Peripheral summary >>> ---------------------------------------------------- >>> Channels: 1 Rx, 0 Tx >>> Timestamps: NO >>> Other Settings: >>> * RF Gain Select - RF Gain Select >>> [key=rfgain_sel, default=4, type=string, options=(0, 1, 2, 3, 4, 5, >>> 6, 7, 8, 9)] >>> * IF Mode - IF frequency in kHz >>> [key=if_mode, default=Zero-IF, type=string, options=(Zero-IF, 450kHz, >>> 1620kHz, 2048kHz)] >>> * IQ Correction - IQ Correction Control >>> [key=iqcorr_ctrl, default=true, type=bool] >>> * AGC Setpoint - AGC Setpoint (dBfs) >>> [key=agc_setpoint, default=-30, type=int, range=[-60, 0]] >>> * BiasT Enable - BiasT Control >>> [key=biasT_ctrl, default=true, type=bool] >>> * RfNotch Enable - RF Notch Filter Control >>> [key=rfnotch_ctrl, default=true, type=bool] >>> * DabNotch Enable - DAB Notch Filter Control >>> [key=dabnotch_ctrl, default=true, type=bool] >>> >>> ---------------------------------------------------- >>> -- RX Channel 0 >>> ---------------------------------------------------- >>> Full-duplex: NO >>> Supports AGC: YES >>> Stream formats: CS16, CF32 >>> Native format: CS16 [full-scale=32767] >>> Antennas: RX >>> Corrections: DC removal >>> Full gain range: [0, 48] dB >>> IFGR gain range: [20, 59] dB >>> RFGR gain range: [0, 9] dB >>> Full freq range: [0.01, 2000] MHz >>> RF freq range: [0.01, 2000] MHz >>> CORR freq range: MHz >>> Sample rates: 0.25, 0.5, 1, 2, 2.048, 6, 7, 8, 9, 10 MSps >>> Filter bandwidths: 0.2, 0.3, 0.6, 1.536, 5, 6, 7, 8 MHz >>> >> > >