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From: Phil Allison on 17 Feb 2010 23:03

"Tim Wescott"

> How much frequency modulated?
>
> If you want something you can hear on a broadcast FM receiver -- you
> can't get there from here, at least not with a crystal oscillator.

** Nonsense.

A suitable varactor diode circuit will pull a 10.7 MHz ( fundamental)
crystal by about 5 kHz.

Sees pages 3 to 5 of this link for typical pulling curves:

http://www.raltron.com/cust/tools/appnotes/Crystal%20Mini%20Primer%20-%20Part%201.pdf

Then one multiplies the frequency up to the FM broadcast band using two
stages of tripling or 9 times.

THEN the frequency shift is also 9 times greater.

Be VERY audible on any FM receiver.




..... Phil





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