[time-nuts] HP 10811 stabilizing time

[Alberto di Bene]

On 2019-07-23 13:01, Charles Steinmetz wrote:

> The later HP5328 "oscillator helper" boards have EFC pots for fine
> tuning the timebase frequency.  This includes the US military versions
> that are so prevalent in the US.  I have schematics showing this with
> both the 10544 (support board 05328-60027) and 10811 (support board
> 05328-60038) oscillators (production shifted from the 10544 to the 10811
> during the 5328's run).

I found on the surplus market a board with a 10811-60111 OCXO. The board is marked
5328-20027. I suppose it is for the HP5328 counter.

There is a trimmer marked "Fine Adjust" and two capacitor trimmers marked C12 and C15.
I suppose the "Fine Adjust" trimmer is for the EFC, but don't quite understand what those
C12 and C12 trimmers are for...

Anybody knows ? Is there any schematics of this board lying around ?  Thanks.

73  Alberto  I2PHD