Regarding Observation 5047933 …
The ground station picked something up around 3:47, but I can’t tell what it was. Is this interference, a signal from the satellite, or something else?
This is also a terrestrial/noise, I guess.
By checking M6P’s positive observations, this seems to be a valid observation: Observation #4210091, for example. It has definitely 2 FSK signals, close to the center frequency, and the decoded data also seems to be valid
Or this is another good example, with 4 decoded, real packets: Observation #4053070.
Unfortunately, there are thousands of bad vetting in the database, for many of the satellites.
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@notcaptpicard one way to tell if it is a signal from the satellite is to look at the bandwidth. The satellite is supposedly transmitting 9600bps so we would expect it to have a signal that is up to twice as wide, or about 18-20kHz. The examples that @bcsak sent show very short packets that extend to nearly ± 10kHz in the waterfall, so they look convincing. They are the thin white lines and not the traces that move frequency. They stay in the center of the waterfall plot, which means the signal is from an object that is travelling at the right velocity to give the predicted doppler shift. So we can be fairly confident it comes from something in the right orbit.
Good luck,
Chris
G0KLA
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