[time-nuts] Adjusting nominal frequency of FTS 1200-100 OCXO?

[Christopher Hoover]

I've been debugging a FTS 4050 with the 5000M module.

It looks like the problem is the FTS 1200-100 OCXO.   It seems to have aged
to the point that it is very low in frequency.   (Chuck Harris reported a
similar situation a long time ago.)

I have it out of the 5000M and determined that I need to give it +8.8V on
the control to get it within 50uHz of 5 MHz.

The power draw after a short warm up is < 2.5W (on this hot day); it looks
like the oven is behaving.

Has anyone figured out how  to adjust the nominal frequency of an FTS 1200
-100 to recover the EFC range?

Also, anyone have a schematic for any model of the FTS 1200?

Thanks,
-christopher
73 de AI6KG