[time-nuts] Good clean-up oscillators

[Attila Kinali]

On Wed, 23 Jan 2019 17:31:04 -0500
Bob kb8tq <kb8tq at n1k.org> wrote:

> If you take a look at typical TCXO’s and XO’s in a real world environment, 
> their noise is higher than a similar 
> OCXO even at 100 Hz. If you are cleaning up something like a Rb, your loop 
> may well be below 1Hz. 

I always assumed, this is because they use cheaper resonators, with 
lower Q for the XO and TCXO than for the OCXO. E.g. most HC-49 case
AT-cut crystals are in an (inert) gas at approximately 1bar pressure.
My guess would be, if the same crystals would be used, the phase noise
levels should be comparable down to 100Hz at least, maybe even 10Hz.

If my guess is wrong, what would be the reason?

			Attila Kinali

-- 
It is upon moral qualities that a society is ultimately founded. All 
the prosperity and technological sophistication in the world is of no 
use without that foundation.
                 -- Miss Matheson, The Diamond Age, Neal Stephenson