Create SOP for setting SDR receiver gain #22
Description
Any SDR receiver gain needs to be set properly to work with the LNA connected to it's frontend. The gain setting needs to be increased just to the point where received signal increases, but just before the noise level increases. This results in the best SNR performance.
This is done by looking at the SDR receiver using a SA (Frequency Sink) while receiving something like a CW signal on the design frequency over the air. Then the SDR's receiver gain is increased, watching the design signal increase, and then stopping the adjustment just as the noise floor starts to increase. Maybe then back off a hair? Once achieved, the gain level needs to be recorded for future flowgraph use.
The SOP needs to specify the procedure and tools needed to do this. There may also need to be details of how to do it in the peesence of high terrestrial noise. This was done several times by Theo and Glenn (ebv1 and kj7su stations), but needs to be written for everyone to do.