[time-nuts] Z3801 saga

[Magnus Danielson]

Fellow timenuts,

The automation fell in my lap today. The Allan deviation plot show clear
evidence of CW modulation (traditional ripple). Turing over to frequency view
there it is. Actually, it has both varying amplitude and frequency. As
frequency lowers, so does the amplitude in frequency deviation. When it hits
around 450 mHz on the 10 MHz, the Z3801A goes into holdover.

Now, it seems that there is some source of pumping up and down. I am suspecting
something like the oven control pumping. The longer time it spends the longer
the temperature goes up and down and thus modulate the frequency more and more.

Somebody sitting there with the outer and inner oven control schematics. I've
only seen parts of the inner one.

Does this ring a bell somewhere?

I'm off for a eh... escapade... so I may check email tomorrow morning, but then
I'm out in the woods listening to strange music, drinks, friends... ya now!

Cheers,
Magnus