[time-nuts] uC ADC resolution (was: Poor man's oven)

[Richard (Rick) Karlquist]

On 6/11/2017 6:09 AM, Magnus Danielson wrote:
> Hi,
> 
> What papers would you recommend reading?
> 
> One of the things that we experimented on and improved was the passive 
> wall to prohibit quick cooling of oven. A puff of air or the forced 
> convection (fans) needed for other electronics would tie the metal 
> shield very well to surrounding environment. Using a simple plastic 
> wall/box as a windshield has a quite drastic effect at the rate of 
> change in temperature, and allowed the oven to react better to it.
> It has proven a very good strategy to reduce the systematic effect that 
> eats up stability. As systematic effect, it should not be part of ADEV, 
> but if you ADEV it is there loud and clear.
> 
> Cheers,
> Magnus
> 

On the E1938A, we tried externally cooling it by spraying it with
canned "freeze mist" and there was no observable fluctuation in
crystal temperature using the crystal in B mode (20 ppm/degree C).

Rick N6RK