> If I can get that down to under 20ppm (say 1s/day or better) at
> an average ambient (in this country probably 15C-20C) that would
> make me happy.

You could use in parallel with your trimmer (and/or regular cap) a NTC
(negative temperature coefficient) capacitor..  Would help with swings
in temp, but don't know offhand how to calculate what value you would
need or whatnot.

my $.002
--
andrew

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