It looks like Roger has found a design problem that could affect other
converters. I have asked that he post any response from David Tong.
I think the solution may be to reduce the crystal excitation, so the loop
gain in the oscillator becomes degenerative at the fundamental frequency. As
a quick check I find that the 3rd overtone is usually about 30 to 40 kHz
lower than 3 times the fundamental. If a fundamental oscillator is running
'cleanly' you should not be able to hear anything on a receiver tuned to the
fundamental and coupled loosly to the oscillator.
I wonder it this will remove all those signals we just cant quite hear, but
I always think and sending CQ at 25wpm!! Strange I can never quite copy a
callsign.
Cheers de Alan G3NYK
[email protected]
|
