GI4DPE & G0NBD first PSK and longest data qso (yet)
10/9 22:00 local
G0NBD and GI4DPE , established communication , Using a mix of modes ,
psk31, qpsk31 and pskam10. Hampered by adverse noise and deep qsb , an
exchange was achieved over a distance of some 170 miles.
Technically the experiment spanned the development of radio
communications, Finbar , achieving, the linear modulation of his
mosfet class c/d transmitter by amplitude modulation of PSK31 and
QPSK31. Modifications where needed to enable the modulator to handle
tones outside the normal speech band. To ensure minimum bandwidth a
frequency below 100 Hz was used.
On my part, linier transmission of PSKAM10 was generated by use of a
Racal MA1723 exciter audio fed to the 600 ohm line feed , final
amplification by class A solidstate drive amplifier.
A combination of 'Digipan' Psk software, unique in that it allows tone
generation to 0 Hz and Multipsk, generating pskam10. was used for the
test. Reception of the AM signal was facilitated by the selection of
the 400 Hz filter , reception of the full signal was necessary, due
to the low power contained in the sidebands
Graham .
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