Graham,
According to the 'printed word' the PSKAM10 mode is supposed to be
quite robust ..
The printed word is correct, at least to a point. PSKAM10 (only
available in F6CTE's MultiPSK program)is definitely more robust than
straight PSK31. This comes less from the lower data rate than the
transmission of each character twice. It takes up less BW than straight
PSK31.
Its biggest shortcoming appears to be in establishing initial decoder
sync. Sometimes, during a fade, the decoder will go "on walkabout," and
not re-sync for some time. That can be a bit annoying. Patrick suggests
that his PSKFEC31 offers better decoder sync behavior.
I have run PSKAM10 on 137 kHz a number of times, both at full power and
in low power tests over a 200 km path. Jay and I have had several QSO's
in this mode, and it has been well behaved. The mode's noise behavior is
much better than straight PSK31.
Interesting alternatives would be the PSK08 mode in Spectrum Lab, and
JASON Fast. I'm looking forward to seeing how some of these things work
with the more rapid fading at 500 kHz.
Hopefully, someone will give your PSKAM10 beacon a try, and report the
results. The MultiPSK program may be downloaded at
http://f6cte.free.fr/index_anglais.htm .
John Andrews, W1TAG
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