Thread: Self-heating of crystal in inverter oscillator
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Old July 3rd 06, 06:02 AM posted to rec.radio.amateur.homebrew
Ben Jackson Ben Jackson is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 34
Default Self-heating of crystal in inverter oscillator
On 2006-07-01, wrote:
On Sat, 01 Jul 2006 02:23:19 -0500, Ben Jackson wrote:

I suggest a discrete Bipolar or FET where you can control the
operating point of the device better.

If I can't tame this VCXO I will try that. This must be how Manhattan
prototyping branches off into "Ugly"...

Well, this might be the best advice I ever got from Usenet. I fought
every parameter in the 'HC86 inverter oscillator and lost. The fact
that it works great at 14.85MHz and the elegance of using up the extra
gates lured me in. The whole thing is very voltage sensitive (around
1Hz/mV at the output of the gate, making it very sensitive to Rs as
well). This might be due to the propagation parameters of the gate
varying substantially with temperature and voltage.

I built a Colpitts oscillator with a plain old 2N3904 and it hasn't
moved by more than a few Hz in the hour it's been on.

Thanks!

--
Ben Jackson

http://www.ben.com/
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