Indeed -
What happened to WOLF (*) ?
I've just tried Googling (**) it and find practically no
hits. The data mode seems to have been used successfully in
the years around 2001 and on, for a bit, but has faded. The
URL I had for it is now gives the magic 404. Didn't the first
transatlantic contact on 137kHz use this mode?
I guess that as it used 10 baud BPSK, was considered too
complicated for the average LF Op. to generate. No one seems
to use upconversion from audio, and few seem to be able to
make simple PSK encoders. Even for EBnaut, relays are
suggested as the means to reverse the phase (yes, truely !!).
I suppose, to be fair, 10 baud unfiltered BPSK from a high
power transmitter is a bit unkind to other band users.
Andy G4JNT
(*) Weak signal Operation at LF
(**) Other search engines are available - so it has been
said.