Brian, Do you have a GPSDO? If so, with the Loop Open, you can adjust the OCXO to exactly 5 MHz and watch that it is stable. Once done, then select Oper and wait until Beam I and 2nd Harmonic come up. Then hit the Reset Button and watch what happens to the 5 MHz, compared to your GPSDO. If it slews off frequency, then it shows a signal is getting to the OCXO and, likely, A9 is OK. If it stays put, A9 could be a problem. If the 2nd Harmonic falls when you turn off MOD, then A7 is likely OK and the problem is more likely in A8.
Also, when you unplug J1 from A7, Beam I and 2nd Harmonic should fall. If so, A7, again, is likely OK. I have also had failures in A14. Make sure the bulb is not burned out. Do you have a manual? Good luck. Joe -----Original Message----- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Brian, WA1ZMS Sent: Tuesday, September 11, 2012 4:50 PM To: Time-Nuts Subject: [time-nuts] HP OCXO in 5016A..... Does anyone has any info on the HP-00105-6013 Series 1248 OCXO that is/was used in the HP-5061A? I have a newly acquired 5061A that has "issues". It has an FTS tube in it, and while there is beam current and plenty of 2nd Harmonic, the alarm light does goes out, but this unit is not yet a member of the "Green Light Club" in that the continuous operation light fails to light. The control loop appears to try and slew the OCXO way off frequency. My best guess is a defective A7 AC amp module. Time to trouble shoot! :- ) Comments welcome. -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. _______________________________________________ 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.
