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Adjusting the Antenna Trimmer
#1

Hi All,

I'm closing in on my first success. I took a dead 42-PT94, recapped it, swapped out the resistors, fixed up some of the crumbling rubber insulated wiring, and it's playing quite well. Pretty exciting.

In aligning it, I get no reaction from the antenna trimmer. The IF's and the oscillator trimmers act just as they should, but no output variance from the antenna trimmer. What don't I understand? (I'll admit that's a whole lot at this stage of my education).

Alan
#2

Well a few things come to mind. The trimmer on the tuning cap should be set for max volume at the HIGH end of the bc band. It won't have much of an effect at the low end of the dial. Does it have the original loop ant? Any damage? Shorted turns? If not the replacement may not have the proper amount of inductance.
Terry

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry




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