Magnus I am systematically checking every thing. Power is every where, get a very strong 60 MHz with the 5.3125 clearly visible on the spectrum analyzer also counted both with a counter, checked the 85 Hz modulation on the tuning diode, is a small signal but the same on my working M 100. Some is off the M 100 some off the FRS. Working on the Servo assembly. Because of dense packaging it is very difficult to find the output signal, but I am now sitting down with the ohm meter and retracing all the interconnects on the servo board. It is multi layer. Once I have the 85/170 pass I will inject a variable frequency, maybe 85 Hz is wrong. I will keep you posted. The biggest problem is the packing density, very hard to get to the pins of the IC's. Bert In a message dated 4/1/2012 6:56:55 P.M. Eastern Daylight Time, mag...@rubidium.dyndns.org writes:
Bert, On 04/01/2012 07:50 PM, ewkeh...@aol.com wrote: > In the past I have asked if some one has any info of the Efratom M3100. I > have carefully dissected the unit and checked functionality. It sweeps but > does not lock. Lamp signal is strong 60 MHz and 5.xx all work properly and > can be seen on a spectrum analyzer The problem is in the loop and there is > not enough signal into the phase detector. Trying to follow the detector > output is challenging because lack of information and packaging density. > Typical loop frequency in a M100 is 127/254 in this case I see 85/160. I would > expect in a military application they would go up not down for vibration > purposes. Tracing the circuits is also made more difficult because of the use > of mil parts and mil nomenclature. I have most cross correlated and I am > down to one PMI part 38510/11201BCA. Does any one have any info, such a > nice unit, would like to make it work. OK, does all the parts have operational power? Does the modulation work? Maybe it needs phase-trimming for best detection gain? Can you hook up a scope so you have modulation sweep on X and detector response at Y? You should be able to probe around. I had some part success with a similar rubidium, until I had reversed it to such a degree that I knew that it was a power-supply in the thick-film module that had failed. Cheers, Magnus _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.