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rxseger / rx_tools

rx_fm, rx_power, and rx_sdr tools for receiving data from SDRs, based on rtl_fm, rtl_power, and rtl_sdr from librtlsdr, but using the SoapySDR vendor-neutral SDR support library instead, intended to support a wider range of devices than RTL-SDR
GNU General Public License v2.0
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No sound in output #63

Open rrobinett opened 5 years ago

rrobinett commented 5 years ago

I am trying to replace rtl-fm with rx_fm on a Raspberry Pi 3B in order to benefit from improved tuning frequency accuracy and access to all Soapy-supported devices.

Running 'rtl_fm -M wbfm -f 88.5M | sox -r 32k -t raw -e s -b 16 -c 1 - -d' I can clearly hear my FM station.

However, running 'rx_fm -M wbfm -f 88.5M | sox -r 32k -t raw -e s -b 16 -c 1 - -d' I hear dead silence. There are no errors reported and there is clearly an rx_fm output bitstream, so I seem to have misconfigured rx_fm.:

pi@PiB83:/tmp/wspr-captures/AI6VN_VHF_0/1 $ rx_fm -M wbfm -f 88.5M | sox -r 32k -t raw -e s -b 16 -c 1 - -d

-: (raw)

Encoding: Signed PCM Channels: 1 @ 16-bit Samplerate: 32000Hz Replaygain: off Duration: unknown

In:0.00% 00:00:00.00 [00:00:00.00] Out:0 [ | ] Clip:0 Found Rafael Micro R820T tuner Found Rafael Micro R820T tuner Using device R820T: origin=https://github.com/pothosware/SoapyRTLSDR rtl=0 Found 1 antenna(s): RX Found 1 gain(s): TUNER Found 2 frequencies: RF CORR Found 10 sample rates: 250000 1024000 1536000 1792000 1920000 2048000 2160000 2560000 2880000 3200000 Found 0 bandwidths: [INFO] Using format CS16. Tuner gain semi-automatically set to 40 dB Bandwidth set to automatic resulted in 0 Hz. Tuned to 88771000 Hz. Oversampling input by: 6x. Oversampling output by: 1x. Buffer size: 8.03ms Exact sample rate is: 1020000.026345 Hz Sampling at 1020000 S/s. Output at 170000 Hz. In:0.00% 00:00:00.51 [00:00:00.00] Out:8.19k [ | ] Clip:0 sox WARN alsa: under-run In:0.00% 00:00:00.77 [00:00:00.00] Out:16.4k [ | ] Clip:0 sox WARN alsa: under-run In:0.00% 00:00:13.57 [00:00:00.00] Out:426k [ | ] Clip:0 sox WARN alsa: under-run In:0.00% 00:00:23.81 [00:00:00.00] Out:754k [ | ] Clip:0 ^CSignal caught, exiting!

User cancel, exiting... readStream read failed: -1 dongle_thread_fn terminated In:0.00% 00:00:24.03 [00:00:00.00] Out:762k [ | ] Clip:0 Aborted. pi@PiB83:/tmp/wspr-captures/AI6VN_VHF_0/1 $

rrobinett commented 5 years ago

I continue to have this problem

vdleun commented 5 years ago

I had the same problem with my sdrplay rsp1a. I solved it by including the tuner bandwidth (-w 200k) and sdr sample rate (-s 500k).

rx_fm -M nfm -f 144.800M -d driver=sdrplay -w 200k -s 500k -r 32k -g 50 | direwolf -c sdr-1200bps.conf -r 32000 -D 1 -B 1200 -

By firing up rx_fm this way, I now have audio and am piping it into direwolf to decode APRS packets. I checked the audio by running the samen rx_fm command and piping it into sox. Before -w and -s it was dead silence. The values of -w and -s parameters are taken from the output of rx_fm.

Found 1 antenna(s): RX Found 2 gain(s): IFGR RFGR Found 2 frequencies: RF CORR Found 13 sample rates: 250000 500000 1000000 2000000 2048000 3000000 4000000 5000000 6000000 7000000 8000000 9000000 10000000 Found 8 bandwidths: 200000 300000 600000 1536000 5000000 6000000 7000000 8000000