After reviewing my measurements, I see that they might not provide sufficient proof to support my conclusions.
The main deficiency is the noise floor of the measurement system; it isn't low enough. I need to find a way to reduce it, perhaps with a preamp for the meter that has a lower NF.
The C/N ratio of the signal at the antenna terminals is not enough to be greater than the difference between the input of the tuner of -85 dBm and the thermal noise floor at -106 dBm, when a preamp isn't being used.
106 - 85 = 21
This makes it unclear if it is possible to receive and decode a signal with a NM below -15 dB.
I'm looking for an equipment setup that can prove it either way, but I haven't found it yet. Maybe I need to include a preamp for the tuner also.
Last edited by rabbit73; 19-Nov-2017 at 3:32 PM.
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