[R-390] Looking for a 5-25 pF Trimmer

[Bob Camp]

Hi

Ceramic trimmers “freeze up” in a whole lot of older gear. The problem is in
no way unique to these radios. Any time you see one that is “many decades”
old, be careful with it !!!!

The “if I just apply more force it will turn” approach is generally NOT a good
idea with these beasts. 

Bob

> On Sep 20, 2024, at 3:34 PM, Jacques Fortin <jacques.f at videotron.ca> wrote:
> 
> Hi Barry,
> 
> "Frozen" Erie trimmers are a common problem in Collins radios (S-line and
> etc.).
> Glen Zook wrote a procedure to "repair" those.
> But it does not always work.
> When you got a frozen trimmer into the R-390A crystal deck, you have to
> rebuilt the unit entirely (guess how I know).
> 
> About yours now: how much do you need ?
> BTW, remove the rubber insulator: it is only there to prevent the rotation
> of the thin ceramic disk, but what happen most of the time is that the small
> disk "adheres" to the top portion and rotate with...
> I will send you all the replacement parts if you still need those.
> 
> 73, Jacques, VE2JFE in Montreal
> <Ceramic_Trimmer_Repair.pdf>______________________________________________________________
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