[time-nuts] Optimal oscillator topology for diffrent frequency range
Richard (Rick) Karlquist
richard at karlquist.com
Mon Feb 6 08:08:36 EST 2017
Agreed, for low phase noise FLOOR, it is imperative to
take the signal out through the crystal. However, for
close in noise (say ADEV at t=1), the Driscoll has
worked well for me. I have been able to reach ADEV
= 10^-11 at 100 MHz at using suitable resonators.
On 2/6/2017 4:35 AM, KA2WEU at aol.com wrote:
> Not quiet, using the crystal also as filter gives much better numbers ,,,,,
> 73 de Ulrich N1UL
> In a message dated 2/6/2017 7:30:33 A.M. Eastern Standard Time,
> richard at karlquist.com writes:
> I would say the 2 stage "Driscoll" oscillator is the
> way to go. I have had good luck with it up to 100 MHz.
> The first stage has the crystal in series with the
> emitter, but is otherwise a grounded emitter stage.
> The second stage is in cascode as a grounded base.
> The important operating condition is that only
> the second stage limits. First publications on
> it were in the early 1970's (search Michael Driscoll).
> Rick Karlquist N6RK
> On 2/6/2017 1:06 AM, Yeti Yetos wrote:
> > Good morning,
> > What's the optimal oscillator topology for low phase noise (low
> > noise and phase noise floor) for 25Mhz/50Mhz/100Mhz frequency
> > Best regards, Rafal
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