NCS wrote:

> What's the best way to use a trimmer capacitor
> to adjust the frequency of a 8mhz crystal?
>
> I used a 5-50pf trimmer and a 27pf capacitor for c1 and c2,
> but results not so good.  It oscillates, but can't really tune it.
>
> Is there a better way to do it?  Trimmer in series with crystal?
> Add a "Rs"?

Perhaps your expectations are too high.
Most crystals may be "tuned" om;y a few hundred Hertz.

>
>
> - Dom
>
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  |  __O    Thomas C. Sefranek   tcs@cmcorp.com
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