[sdiy] VCO drift

[harrybissell]

LOL !!! The single schmitt trigger oscillator isn't stable for anything...

The only thing you can guarantee is that it 'will' oscillate.

I designed one in as a clock circuit... once.  Guess what happened when I
got some gates from National and some from Motorola...

then guess what happened when the next batch came in   :^P

I did make a sort of cracklebox circuit with this oscillator... no problem its
not intended to be 'in tune' or 'stable'... just noisy...

H^) harry

Ken Stone wrote:

> >How temperature sensitive are the thresholds levels in a 4069,
> >when used in oscillator designs in such as Renes CMOS VCO?
>
> I can't speak for the 4069, but the 40106 Schmitt is not temperature stable
> when running as single inverter oscillators. Stick your finger on the chip
> and hear them drift :)
>
> Ken
>
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