[time-nuts] Oscilloquartz OSA 5515

[Magnus Danielson]

Fellow time-nuts,

Do any of you by any chance happen to have any documentation or possibly 
even the schematic on the OSA 5515?

I have one, at it fails to lock up. The 8655S OCXO heats up nicely from 
5,000166 MHz, with a bit of an undershot and stabilizes at about 
4,999999140 MHz. That for sure looks like the tell-tale of SC-cut 
crystal in that oven. I've been able to persuade it up to 4,999999225 Hz 
as closest using the oscillator trimmer, but that's it.

It would be very practical to get it to lock and behave itself, as I get 
plenty of 5 MHz and 10 MHz outputs, that suffice to use for a varity of 
instruments.

I took the oscillator module out, and was able to trace out input 
transformers, power-splitter, mixer and a line of analog which is the 
amplification and main loop. Then it has a digital integrator for the 
long-term memory it seems. For it's time it seems well built. I could 
probably reverse-engineer it fully, but for the moment I would like to 
focus on other things. I am happy I discovered in my basic test that it 
did not lock up fully to the 5 MHz given.

So, anyway, if someone happen to have the manual & schematic for this 
module, it would be greatly appreciated.

I have emptied and cut one (too big) rack and thrown it away. Time to 
rebuild the lab and make more of it useful. That's when you find bits 
and pieces that may be useful and try to make them all fit into the 
remaining rack. Lots of fun. One thing I need to fix is that 5 MHz to 10 
MHz conversion, and this box already does that. I used to not be able to 
have use for it since I started out with a bunch of 10 MHz GPSDOs, but 
as life goes, 5 MHz devices become more and more frequent.

Cheers,
Magnus