Cannot get the 'FM_receiver' sample gnuradio code to work

Question

I am trying to get the sample code for the 'FM_receiver' sample code working with my limeSDR and it seems not to pickup anything. Here's some screenshots of my gnuradio and its output: I have it tuned to 98.5MHz which I can hear clearly with a typical FM receiver but can only hear static with this. What am I missing?

Answer 1

You may need to set the Device Name in your Audio Sink block. See https://wiki.gnuradio.org/index.php/Audio_Sink You didn't say what OS you have.

If you continue to have problems, I suggest that you work through the https://wiki.gnuradio.org/index.php/Guided_Tutorial_Hardware_Considerations

Answer 2

I observe that while the RF Frequency is set to 98.5 MHz in your LimeSuite Source block the frequency range that is detected by your FFT Sink is centered at 100.1 MHz and going from 99.1 MHz to 101.1 MHz, so we don't really know if the device is receiving any signal at 98.5 MHz. You clarified that you can clearly hear the FM station in your FM receiver. Considering that the flow diagram is set up correctly , I think that you are probably hearing the 98.5 MHz station from a digital radio receiver. That explains why you cannot hear anything with your GNU Receiver. Another way to test your design is by setting the FR Frequency parameter of the LimeSuite Source block to 100.1 MHz, where we can clearly see that you receive an FM signal.