Datasheet/pinout for AT&T RFG-RB Rubidium reference

[nexus]

Hi All,

I was fortunate enough to receive an RFG-RB from a friend. If there is any documentation regarding this frequency reference, specifically with respect to pinouts on the front panel and electrical specifications, I would greatly appreciate it! There doesn't seem to me much technical info out there on the web with regard to this particular box.

Thanks,
Kevin

[ZigmundRat]

P1 - the male DB9 on the left, power connection should be pin 1 +24V, pin 2 GND. It will need about 1.5A to start up and maybe .5A once warmed up.  That warmup should be maybe 5 minutes before it locks, but it might take longer.  AFAIK these were free running and used the paired OCXO unit as a cleanup oscillator. It was only the later models that were GPS disciplined. Hopefully that helps.

[nexus]

I see; thanks for that info! I've heard that the reference outputs are quite ugly in terms of both phase noise and THD. I probably would want to pair it with a VCOCXO as a cleanup oscillator like you mentioned. Would be a good learning and design challenge for a newbie like myself to learn about PLLs and other clock management building blocks.

I wonder if the RFG-RB box is capable of being fed a discipline signal. The DB9 marked "interface" might be some kind of digital bus that also provides trimming capabilities. I just wish I could find some literature on this thing... it has to be out there!