[time-nuts] Datum PRS-50 monitoring software

[va2hdd at ebox.net]

Hello to all members.

I recently purchased a Datum PRS-50 that looks like a spare unit, almost 
mint. When I connect it to a lab PS set to 48 volts the current 
stabilise at around 0,5 Amp, the LED's light up according to the 
sequence described in the manual and the unit eventually goes into 
cesium lock with a very nice 5.000000046 MHz output.
The cesium lock LED stays on for a while, then the unit goes in alarm, 
then back to cesium lock, then alarm ...  I suspect that the ion pump 
need to improve the vacuum in the CS tube.  I tried to use the "monitor 
3" Windows software to watch ion pump current but I was never able to 
get it communicating both with front or rear connector, I installed the 
software on a Windows 10 PC and used a USB to RS-232 dongle.  I tried 
three different chipset USB-232 adapters with the same result.  My unit 
does not have the "TL1" option, and on page 2.2 of the manual in table 
2.3-1 it is mentioned that without the TL1 interface I should be using 
the DOS version (Monitor.EXE).  I tried to find it but had no luck.

Best regards,

Claude VA2 HDD