Hello Alan and all other LF-friends,
On Sunday an unusual noise aleted me to a PSK31 signal on 137.6, I swapped
programs to see Geri just finish working DL7YA on X-mode, and then
continue
with Wolf DF0WD also cross-mode.
Thank you for your report on my PSK31 signal and the log you send me. It
shows, that also PSK31 is good for long-distance QSOs close to the noise.
The QSO with Wolf, DF0WD, by the way, was a full PSK31/PSK31 QSO. Wolf was
only running lower power than usual, bus he is one of my nearest neighbors
(about 110 km away), so I copied his signal 599. The QSO with DL7YA was
PSK31/CW, quite an unusual combination, but we had a lot of fun ...
I managed to get my new Hagenuk EX-1001 QRV on 136 in SSB, producing about
1 or 2 Watts from an AD2030 (tnx Rich, OM2TW for the schematics, it woks
great, no problem!). To avoid multiples of my audio signal appearing within
the band, I uses 135.500 kHz upper sideband and fed a 2000 Hz PSK31 signal
into it, ending with a more-or-less clean 137.500 kHz signal. As soon as my
PA is back on the air again, I will continue to test various computer
generated modes that require SSB.
Another thought: we in Germany are allowed to use any mode with a maximum
bandwidth of 800Hz. I know that normal 2.1 kHz wide SSB signals havne been
transmitted in the early days of LF in the UK. Has anyone ever thought of
"Slow-Audio" instead of Slow-CW? My idea is to use an audio editing program
such as Cool Edit (available as shareware) and reduce the running speed, so
that a normal sharply filtered (the filter is a build-in feature of Cool
Edit) 2.4 kHz audio signal is compressed into 800 Hz or an even smaller
bandwidth. The same software could then be used to expand the signal again
and make it audible. I plan to do some local testing (and yes: I will run
those on reduced power using time slots when normally there is no traffic,
I do not want to block the entire band with such a funny signal ...) to see
what can be achieved ...
Best 73
Geri, DK8KW (W1KW)
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