Ggrx software record and mode

Hello,

My name is Pablo, we had worked on various issues thanks to the satnogs network. We can decode and process data (using direwolf and our backend), we even publish a general purpose GS (https://ugs.unlam.edu.ar/#/browse/mine/demodash). Now we are going to work in our ground station and that is not my strong point. As far as I concerned, just for testing, I should record the audio from the pass (I have no problem with gpredict and SDR) and then decode with direwolf, just like the audio from satnogs. My question is, how should I record the audio in gqrx?
Should I use FM mode to demodulate? What mode should I use if my satellite transmits FSK? I can not find documentation about it and I am not sure if it is necessary to work with gnu radio

Thanks in advance…

Most likely ‘Narrow FM’ mode to record.

Which satellite?

1 Like

Thanks satcolintel5,

Yes, I suspected it but I didn’t sure.
I started with UHF satellites, because I have a yagi anntena designed for those satellites.
SPOOQY-1, ELFIN-A, ELFIN-B, TIGRISAT, BUGSAT-1
Now I have a record from Lume-1 and sound good, I can heard the beacon each 20 seconds. Also a I found this source of information:


I will continue recording using Narrow FM and I will try to decode.

Thanks again.

1 Like

Ok, the problem is solved. I 'm going to write the steps, they can help some newbie in RF like me. I used an almost salf-made yagi antenna. I recorded the wav audio using FM as demodulator mode in GPRX software. Then I use GNU Radio and the bugsat1 decode, I’m not sure if the decode is by default in GNU Radio or is created by Daniel Estevez. (https://github.com/daniestevez/gr-satellites). I will copy the GNU Radio chain image soon. Then I press play in GNU Radio y decode data is available. Now It’s time to automate the process…a new satnogs ground station is comming :slight_smile:

Thanks for your help.
Pablo

1 Like