[Milsurplus] [Boatanchors] Mica compression trimmers?

[Robert Downs]

BTW, it also occurred to me tonight that the term "mica compression trimmer"
is actually misleading as the compression of the mica dielectric doesn't
have anything to do with how the things work.  A more correct but definitely
less convenient to write name for the things might be "mica and air
dielectric variable spacing trimmer capacitor". 

Also, I didn't realize until a few years ago that the mica trimmers also
came in a "butterfly" version and that many of us have at least one radio
that uses one.  The radio being a BC-611-A...E.

Robert Downs

-----Original Message-----
From: boatanchors-bounces at mailman.qth.net
[mailto:boatanchors-bounces at mailman.qth.net] On Behalf Of McDonald, J
Douglas
Sent: Monday, October 26, 2020 14:36
To: boatanchors; boatanchors at theporch.com; Milsurplus
Subject: Re: [Boatanchors] Mica compression trimmers?

Its all a matter of degree.

I've seen such things with two adjustments: one for capacity,
one for temperature coefficient, which goes through zero. That was done with
a bimetal strip.

Doug McDonald