A great result there Domenico.  It is nice to see such
a decode where the signal is invisible, the constellation
is just a central blob and there's no significant squared
carrier on the spectrum.   But there was enough squared
carrier S/N that a phase search wasn't necessary.

Yes a new LF distance record, in fact an absolute distance
record for EbNaut, beating the previous W4DEX/DL0A0 record
achieved at VLF on 5th Jan.

It seems that coherent signaling[*] can be used quite well at
LF, even up to one hour duration.  Perhaps longer?

[*] specifically, where the signal is too weak to extract a
running reference phase, thus relying on stable propagation
phase for the duration of the message.

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Paul Nicholson
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