Al, W6LX, just wrote a treatise on accuracy that should be read with diligence.
I
recently asked for assistance on this reflector and received it, and I realigned
the 10 mHz oscillator and the bfos. My Elmer for this work was a local Physics
professor and ham, Mike, K8LG, who has fancy signal generating and measuring
equipment for his work in the VHF and UHF area.
We measured an 80 Hz error at the 10 mHz oscillator, and I was ready to hit the
ceiling, but he immediately did the math to show how small an error that was.
We
got it to 20 Hz and then he said that going further was silly, since he could
not
even guarantee that his $600 counter was necessarily better than that without
calibrating it against his $1500 reference oscillator, which, at the moment, was
not available to us. Besides, the capacitor is so large that every bump made a
random jump of far more than 20 Hz.
Al is right on, and I will be more careful about what I say about Ten-Tec
frequency
calibration in the future. Not that we should not try to keep things right,
just
that we have to realize that these errors are to be expected over time. By the
way, I would like to add a public "thank you" to Scott at Ten-Tec and Steve,
N4LQ,
for their recommendations.
146 (3 dB over 73),
Jan
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