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.
Next, I go to the part where you determine the BFO range. After hitting
Band+, I get a reading of 4917.54 kHz. The manual says you need >= 4916.3,
and it's usually between 4916--4917. Maybe a tad high, but looks good to
me. After hitting Band-, I get a reading of 2456.11 kHz. The manual says
it must be <= 4912.7 (which it most certainly is) but it is usually about
4909--4912 (which is isn't, by a long shot). This results in a range of
2461.43. The manual says it must be >= 3.6 (which it is, by a lot), but
it's typically 4--6 kHz.
It looks like I'm meeting the letter of the law based on the >= and <=
requirements, but I'm nowhere near the typical ranges on the BFO low freq.
and range.
Following this test in the manual is some info on what to do if the
frequencies are too high or too low:
First off, I did not use a frequency counter to adjust C22 on the control
board, I used a separate receiver and hooked up a wire from its antenna
jack to the 4 MHz crystal, as described in the manual. This resulted in me
turning C22 less than 30 degrees counter clock wise (anti clock wise). This
seems reasonable to me, so I don't think C22 is off by very much. However,
I think I might want to try using a frequency counter, to get a little more
accuracy in calibration. Could anybody recommend an affordable frequency
counter? I've never shopped around for them, so I have no clue as to the
price, etc.
The third point mentions I might have shorted out part of L33. Looking
under a loupe, I did not see any evidence of a short, and in fact, I can
slide L33 underneath R116, it doesn't appear that heating R116 affected L33.
The fourth point mentions L33 could be broken. I put my DMM on the tiny
leads attached to R116 and got 1.7 Ohms. Does this sound reasonable?
The final point says to check the capacitors and diodes in the BFO circuit.
After another quick look, this appears to be OK to my eyes.
Any help would be appreciated!
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