I would report my experience with an EFRATOM LPRO with a similar problem, maybe this could help. The sweept frequency was always below 10 MHz, so missing the opportunity to lock. The sweept VCXO control voltage at the monitor pin was correct, but at the varactor it was too low. The problem was in a faulty (leaking) SMD ceramic capacitor on the control voltage line to the varactor. Once replaced the capacitor, the LPRO rose again. So, I would suggest you checking the voltage at the varactor. Antonio I8IOV
> I have a Temex LPFRS rubidium standard that from > all indications appears to have an internal xtal osc > that has drifted beyond what the control loop can > correct for. > > Before I take the unit apart to try and manually trim > the XO, does anyone has an internal schematic for it? > (I have the operation/user manual already.) > > Has anyone else done this type of repair on such a model? > > Thanks in advance, > -Brian, WA1ZMS/4 _______________________________________________ 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.
