Observation 7403732: NOAA 19 (33591) - weird waterfall

Regarding Observation 7403732 …-S
can someone help me with whats going on here? I’m trying to adjust gain via the satnogs since i had to repair my antenna. I use a HackRF LNA with my RTL - SDR, using USB power, and now will try the RTL LNA with bias-t power.

Regarding gain shown in satnogs-setup, what are the differences in GAIN_MODE, what are the particulars in the ‘overall’ and ‘field’ settings? If i tune the SDR’s gain using soapy and say, cubic sdr, is there a dynamic gain setting in those clients?

a frequency range that I’m not too familiar with. much easier to test against known objects.

iirc, soapy has a layer of gain control that has internal algorithms to set the sometimes many stages in a tuner/sdr. this abstraction makes it possible to specify gain in one value, this is the overall mode and is simplest to use.

If you use other drivers for the sdr, or other sdr’s that doesn’t have this abstraction, then the individual gain settings might show up. using gqrx directly on the host for example, you can (depending on installed sw) use the direct rtl=0 driver or soapy. satnogs flowgraphs is only using soapy these days, so using cubicsdr that is using soapy will make sense.

setting the gain can be followed by observations for some hours or days, adjusting up or down and doing a bunch of obs to see how it behaves, adjusting again if needed etc.

I will say thou, for a rtl-sdr with a lna at the antenna, you should probably be below 20dB. I have a complex setup with two antennas and I’m using 3.7 as gain on a r820t2. ymmv etc.

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