Excellent catch by both you and Jim, K4ZM, who replied off line. A flaky
input stage to the counter certainly would fit the symptoms.
Please, never be shy about speaking up on the reflector! That's what makes
this forum so valuable.
It's been nearly four years since I built old number 1289 and
I've come to the Alignment and Test, Part II. I think I'm having a problem
under the BFO test.
Following the instructions, I switch to 40m, hook up the frequency counter
to TP2, and get a reading of 4913.52. The manual says I should get
something between 4908 and 4918. So far, so good.
Jason,
Yes, 2456 kHz IS way too low - in fact it is quite out-of -bounds - and is
close to only half the frequency that it should be.
First thing to check is soldering, then re-check the soldering, and when you
are finished, check soldering again. Use the schematic to identify those
It looks like the counter is only registering half the frequency and it's
really at 4912 kHz.
I don't think it's physically possible for the BFO to oscillate down there.
Certainly not under crystal control. C22 won't vary your counter time base
enough to cause anything like that sort of error.
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