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Old May 20th 07, 03:47 PM posted to rec.radio.amateur.homebrew
Uncle Peter Uncle Peter is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 189
Default VFO.... Zero TC caps


"Jack Schmidling" wrote in message
...
I am in need of zero tc caps for my VFO project but can't seem to find any
info on them. Who makes them? What are they called?

Digikey has some with tc's of 200 ppm but that aint zero.

The also have some that are 0 +/- 500 ppm and that makes no sense.

I need two at 1000 pf.

Thanks,

js


Don't forget, a lot of the drift is caused by the inductor in the resonant
circuit, and it will have a positive coefficient. Most VFOs have some
compensation using a cap with a negative temp coefficient to compensate.

Pete