[MRCA] Trimmer Capacitors

[D. Platt]

Folks,

As I mentioned in an earlier article in /Electric Radio/, the ceramic 
trimmer capacitors used in the four "modules" in the BC-348( ) receivers 
are further showing failures.  Note that this does not include the J, N, 
and Q models as they have an entirely different variety of trimmer.  I 
have just completed going over three more BC-348 receivers, one Q model, 
and two R models.  Both R models had capacitor issues with a total of 
four failed capacitors.  In each case, the capacitor was without the 
retaining collar thus allowing the spider to spring back, effectively 
shorting out the capacitor.  Fortunately, I had a few spares was was 
able to simply (sic) remove and replace each defective component.  At 
this point, though, I'd to again admonish all to inspect their affected 
BC-348 receivers.

As a preventative, one might consider spraying some DeOxit on the front 
of the capacitor, prior to adjustment.  This may relive any corrosion 
between the hex collar and the fixed collar, below.  If one always 
adjusts the capacitor via the screwdriver slot, and not the hex head*, 
there's not much else to do to avoid a failure.

Regards   Jeep - K3HVG

* In most cases, the hex head is recessed and can't be used, anyway.
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