On Thu, Jun 11, 2015 at 7:17 PM, Nick Harrison <hnick...@gmail.com> wrote:
> Hi everyone, > > I recently started playing around with gnuradio, and being the beginner > that I am, wanted to begin by listening to a close by radio station. I > basically followed the instructions on > http://www.trondeau.com/gr-tutorial/ and used the uhd_rx_cfile with the > following command: > > > *uhd_rx_cfile -a "addr=192.168.10.2" -g 0 -f 97.1M --samp-rate=500k -N > 5000000 radio_sample_97.1Mhz.32fc* > Below you can find the image of the IQ data and the PSD that I got when I > used *gr_plot_psd_c * > http://imgur.com/kFpqK25 > > But when I used the fm_demod.py to playback the captured data, it comes > out completely scrambled. Am I missing something here? > What do you mean by "scrambled"? That can mean a handful of different things in this domain. Also, you set the gain to 0; you might want to increase that, though it looks like the PSD is showing a decent amount of signal. When plotting the image the way you did, skip into the file a few thousand samples (pass -s 4000 to the gr_plot_psd_c script) to skip the start-up transients, which are obscuring the signal. You also are bringing the signal in at 500 ksps. Make sure that the script to play back the FM signal is set up for that (it should be based on that tutorial page, but you'll want to verify). Tom
_______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
