I have a model 234 Speech Processor in use with my OMNI-D. The processor
seems to work fine (increases average power on the wattmeter) however while
listening to the OMNI-D/Processor combination in a second receiver, I
realized that the Passband control has no effect on the audio
characteristics. Microphone is non-amplified D-104.
According to the 234 manual, the Passband control sets bias to a varactor
diode which acts to shift the BFO frequency slightly. I checked this bias
voltage and it ranges from approx. 0.2 - 7.5v over the full excursion of the
Passband control, so now I suspect the Varactor diode itself. Should I be
looking elsewhere? Any special tests required to confirm a varactor diode
is behaving correctly?
Many thanks,
Barrett Thompson / KE4R
Fayetteville, GA
KE4R@arrl.net
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