search

argilo / gr-dsdcc

GNU Radio block for DSDcc
7 stars 0 forks source link

No sound when running gr-dsdcc #3

Closed iman432 closed 6 months ago

iman432 commented 6 months ago

Hi,

I complied and installed gr-dsdcc(also DSDcc and mbelib ) and example grc is loaded successfully. i just changed RTL to USRP for working with my SDR,but when running example grc there is no any sound but radio signals are receiving based on graph.its worth to say with another grc can get analog radios and sound is normal. i also attach my grc, its appreciated to share your opinion if something is wrong. USRP dsdcc.zip

argilo commented 6 months ago

The flow graph works for me. The only error I noticed is that the USRP source's frequency should be set to freq - offset rather than freq, to compensate for the 100 kHz offset applied in the Frequency Xlating FIR Filter block.

iman432 commented 6 months ago

Thanks for your response. I also changed freq - offset but still no sound in output.

argilo commented 6 months ago

Frequency error can be a problem. Make sure the demodulated FM signal is centered at 0 Hz hen receiving a signal. You may need to adjust your receive frequency by a few hundred Hz.

Also, dsdcc is not perfect and can't demodulate all digital signals. It worked for a nearby DMR signal when I last tested it.