On Tue, 22 Jul 2003 17:03:57 UTC, Pat Richardson
wrote:
B+ is within spec - there was a short from the original construction
placing the wrong bias on the frequency shift connection (bet someone
found this thing REAL frustrating to tune on LSB!) - that was fixed
earlier in the restoration, though, and is not related to this
problem.
I'm guessing that you're close to getting it going.
Thanks - it's a fun unit to use (and would likely have been the one I
would have had if I hadn't been lazy and got my ham kicense back when
I first wanted to, in 1966....) - would be more fun if the dial
matched the actual frequency, though!
de ah6gi/4
Thanks, Pat
Then I'm guessing that there is *one* bad cap or bad solder joint in
the LMO. I don't think that adjusting the trimmer is a good idea.
I'd especially avoid even thinking about touching the plates on the
tuning capacitor.
If you can get a schematic for LMO, you might be able to "calculate"
the cap that would shift the freq by that amount.
When I had the cold solder joint on the temp compensating cap, the
symptom was that the LMO freq would jump about 20 kHz during
operation.
I found it by listening to the XTAL calibrator on the receiver and
pushing on the caps with a diddle stick. One cap made the freq jump
and jump back.
As I said, I think you are close to finding the problem.
--
de ah6gi/4
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