[time-nuts] Lucent GPS "RFTGm-II-Rb"

[Charles S. Osborne]

Wonder if anyone on the list has information about a Lucent Rubidium locked
to GPS unit I have? Its relatively new, maybe five years old. Purportedly to
be from a failed cell site venture that caused the unit to be sold surplus
having never been installed. The nomenclature on it is:

Lucent: KS-24019 L109  which I assume may be an in house part number or
contract number.  The model number is:  RFTGm-II-Rb .

I've posted some pictures at:
http://campus.pari.edu/gps-freq/Lucent560F.JPG
http://campus.pari.edu/gps-freq/Lucent561F.JPG
http://campus.pari.edu/gps-freq/Lucent562F.JPG

The unit comes up and locks an OCXO to GPS. Then after some more warm up
time it switches over to the locked Rubidium side and the OCXO switches to
become the standby.

My problem with it is that when I come back the next day the Rb side has
faulted out and pushed the system back onto the OCXO as the main online 10
MHz source. Its unlikely the Rubidium lamp is old enough to be a problem, or
that the initial frequency adjustment has drifted out of range.. though I
suppose its remotely possible.

Have been running the unit on 24vdc but would try more if I thought the
normal -48 ~ 56vdc telco battery strings were used with this. It gets warm
enough on 24vdc that I didn't want to chance it until I asked. I know if its
a switcher that it might actually run cooler on higher voltage due to a
proportionate drop in current. Just haven't had a chance to reverse engineer
it all.

I see RS422 labeling on some  of the ports. But without more info I'm
proceeding with caution and somewhat at a standstill as to what's going on.
Anyone have any experience with these units?

Thanks,

Charles S. Osborne, K4CSO
Technical Director

Pisgah Astronomical Research Institute
1 PARI Drive, HC 73, Box 638
Rosman, NC 28772-9614
http://www.pari.edu
828-862-5813 direct
828-862-5554 main
828-862-5877 FAX
cosborne at pari.edu