Frightening the yaks, Dale Parfitt just had to say:

re uneven plates: The linearity will suffer but unless you're
calibrating it to something (tuning dial, antenna load) that
shouldn't matter.

I don't see anything linear in F vs C for a resonant circuit. In fact, in
order to make it anywhere close to linear, one has to go to extremes with
the shape of the plates.

My bad. Not linear in the sense of d-pF/d-theta = K. But more
the idea of no sharp changes for slight adjustment of the rotors.
Continuously differentiable, I should have said.

But if a linear variable cap *was* desired, the plates shouldn't
be all that hard to fabricate.



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This calls for a careful blend of
clever psychology and extreme violence.
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