Rubidium Lamp Voltage

It is the voltage of the output of the op-amp that amplifies the output of the photocell that is being measured there. Approx 5 to 12V is healthy, if 3 Volts, you need a new lamp.

good luck...

modules

anyone

output

is

Lamps are not free nor can they be installed other than in the factory.

If there is Lamp voltage and your not getting lock, there is an oscillator adjustment which you might try. Use only a non-metallic adjustment tool and try tuning the pot a quarter turn "counter Clockwise at a time. Wait a few seconds to see if you get lock. then try again. If there is no lock by the time you get to max, you can try "Clockwise" slowly, however If you reach less than two turns to the end of travel the oscillator is DEAD.

Efratom was purchased by Datum, six years later it was sold to Symetricon. They might still service it, but it is EXPENSIVE! These oscillators were about %5,000 to $7,500 in small quantities new! Test-Equity some times has some refurbished to sell.

Dan, do you agree? Carolyn gave me the instructions!

Hi,

Thanks to the both of you for that information. In fact the standard I have that contains the FRK-L is in good working order and locks fine after a few minutes even though the lamp voltage is down to 5.5. It is just that on the schematic, the EFRATOM subassembly for the RACAL-DANA 9475 is shown as a simple block and so far I haven't been able to run down a copy of the internal circuit. I have a spare surplus lamp arriving in a few days although I've had to take it on trust that it doesn't have too many hours on the clock. Unfortunately the mounting boss is slightly different to mine but I hope to release the bulb from this and get a new fitting turned-up. I am able to carry out basic confidence checks against off-air standards and, as my requirements are modest, the odd digit reduction in the 'n' of 'parts in 10^n' is not of concern. As penance for my sins in a former life, I once had charge of a calibration lab where the frequency sources were Rubidium referenced. They were dumped when the cost of new lamps or trips back to the manufacturer from the Middle-East became greater than new GPS-disciplined oscillators. Thanks - Joe

internal

than

There were no schematics released! You will be unlikely to find one. I only saw schematics because I quoted the upgrade of the FRK, but there was no contract. I had to return the one schematic I had, and Carolyn said it was an earlier version anyway. Carolyn was the one who assembled and tested the units for compliance for eleven years.