[time-nuts] Datum FTS-4040A Cesium standard

S. Nestra pe1rks at xs4all.nl
Thu Aug 14 18:24:55 EDT 2008


Hi,

I have a problem with a FTS-4040A standard, the LED major fault stays on forever.
When I use the monitor program from Symmetricom I see that my OCXO stays 
cold and I have no Cesium oven voltage. The OCXO does feel warm so this 
one is warming up, I don't know if the cesium oven is warming up since I 
can't feel any heat from the CBT.
I also don't see any current from the ION pump.
After opening the unit I found a burnt resistor R1 on one board, I don't 
know what it's function is but I would like to know the value of this 
resistor so I can replace it.
So here is my question: does anybody have any technical documentation 
for this unit and is it possible for someone to lookup this resistor in 
his standard so I know the value( pictures included for position).
I think I have a power supply problem.
I welcome all suggestions.

Greets,

Stijn Nestra

Link for the pictures and the list of 
faults: http://82.95.123.226/fts4040a/




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