There are a couple of 20 uF axial tantalum electrolytics across the B-C junctions of the pass transistors for both the lamp and cell heaters. They were open in my 5065A when I got it, and there was some overheating damage on the lamp driver PCB. Correlation != causation, but since I'm not sure what those capacitors were actually supposed to do in the first place, I think they're worth checking.
-- john, KE5FX > -----Original Message----- > From: [email protected] [mailto:[email protected]]on > Behalf Of paul swed > Sent: Friday, October 29, 2010 6:02 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] HP5065A Rubidium 2nd Harmonic Readings > > > John, > Interested. How might you connect the oven controller to what he > is seeing? > Bad caps causing it to oscillate, 60 hz modulation, ...... > I have a 5065 so am always interested in tid bits that I read. > Thanks > > On Fri, Oct 29, 2010 at 12:34 AM, John Miles <[email protected]> wrote: > > > How's the photo current? Does it vary as well? If not, I > don't think I'd > > be too worried about the physics package. > > > > I would, however, check the electrolytics on the oven controller board. > > You > > don't want an oven controller failure. > > > > -- john, KE5FX > > > > > -----Original Message----- > > > From: [email protected] [mailto:[email protected]]on > > > Behalf Of Brian Kirby > > > Sent: Thursday, October 28, 2010 9:15 PM > > > To: precise time > > > Subject: [time-nuts] HP5065A Rubidium 2nd Harmonic Readings > > > > > > > > > I recently had a long term power failure and ran out of UPS time. The > > > power was out over a day and when I returned home, it had > been restored. > > > > > > The rubidium recovered, I hit the logic reset button and start and got > > > the green light. > > > > > > I made some meter readings, and noticed something I have not seen > > > before. The 2nd Harmonic reading is showing 30 and its bouncing up to > > > 31 about every 2 to 3 seconds. > > > > > > Otherwise, the unit seems to be performing nominal. > > > > > > Anybody ever seen this ? Hope its not trying to tell me > failure of the > > > cell is on the way... > > > > > > > > > Brian - KD4FM > > > > > > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
