Edgar wrote:

> To obtain a 92 uHz bin width in Spectrum Lab the settings ...

... indicates that it takes 4.66 hours for one window.

You don't need a spectrogram, just a single 3 hour spectrum.

Both ends would need GPSDO and also PPS at the rx soundcard.
And even then we don't know if the path is stable enough and
you could still be dissapointed.

Joe wrote:

> [8]K19A 1 Second symbols 25 characters 500 watts. 2100 UTC.

That should make for a massive signal and an easy decode.
... it did:

 21:00 Eb/N0 = 11.1 dB
 21:30 Eb/N0 = 7.0 dB

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Paul Nicholson
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