[time-nuts] How can one measure ADEV of a good oscillator?

[Richard (Rick) Karlquist]

On 12/1/2014 4:08 PM, Bob Camp wrote:

>
> Others did a similar thing by simply taking production OCXO’s to the limit of their EFC range. That let you do a coarse sort to find some number of “likely” units. Next step was to pop  a few of them open and short this or that out to get a reasonable beat note. Numbers in the 10 to 20 Hz range were pretty common. After that a single mixer setup followed by a simple limiter got things good enough to screen the production lots.
>
> Bob
>

I am fairly sure they would have done that if it was workable,
to avoid special crystals.  One rather huge problem with a
10 Hz beat note is that you are never going to measure ADEV
at short (<1 second) sample times that way.

Rick N6RK