> For those of you who have never seen a skimmer operating, it
> does NOT give an absolute signal strength, it give an SNR value.
To translate SNR into absolute signal level it would be relatively
straightforward and inexpensive to inject a signal into the receiver's front
end from a calibrated signal source - say, -20 dBm - at or just outside a
band edge. The signal would not be radiated and so not subject to any rules
pertaining to transmitted signals. A crystal oscillator and an attenuator
would suffice. If the signal source was keyed to be recognized by the
Skimmer ("CQ CQ CQ de CAL CAL CAL") it would become part of the spot
database without any post-processing being required. There are other
receiver linearity issues to deal with but this would be an easy first step
that would enable widespread post-processing and open up the discussion.
73, Ward N0AX
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