Changed Sample Rate of IQ Recordings

After investigating an issue with the decoder on my stations after a SatNOGS upgrade around June I finally figured out that the sample rate of IQ recordings changed from 48 kHz to 50 kHz. Is this an intended change?

Also I could not find any documentation of the configuration so far. As a suggestion: maybe this is something we should include on https://wiki.satnogs.org/SatNOGS_Client_Setup

Regards from Munich,
Martin

To my knowledge, the sample rate of the recordings will vary depending on the value for the satellite’s transmitter(s) in the satnogs db.

The sample rate will be higher for a transmitter that uses larger bandwidth.

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Oh, interesting, that would be a smart feature. Do you remember where to find the documentation or the implementation of it?

In my case the transceiver did not change, it was the same 12.5 kHz BPSK signal of MOVE-II. Maybe the dynamic setting you mentioned assumes an oversampling factor of 4 but did round to 12 kHz before the update? Would explain the difference…

Source code for the scripts is located at https://gitlab.com/librespacefoundation/satnogs/satnogs-flowgraphs

I am not sure if it helps, but https://wiki.satnogs.org/Understanding_satnogs-flowgraphs seems to have a pretty good description of how the flowgraphs work.

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Thanks, that helped a lot. And just in case someone else has the same issue with IQ bandwidth: it seemed there was in fact a small commit changing the the calculation.

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