Great question. I noticed the same on my dead unit. That indeed may be why I had to readjust the 3500 supply as I recall.
On Sun, Jul 11, 2010 at 11:32 PM, J. L. Trantham <[email protected]> wrote: > Has anyone ever replaced a high voltage lead on an HP Cesium tube? > > I have a 5061A that required prolonged pumping at +6000 VDC to get the Ion > Pump current to go down enough to allow the unit to turn on the CS Oven but > then would slowly increase to the point that it would again not let the CS > Oven turn on. > > At +6000 VDC, the current would be about 1400 uA but only about 30 uA at > +4000 VDC. It got me to thinking that there was some sort of HV breakdown > going on. On inspecting the tube and HV lead more carefully, I found the > +3500 VDC lead cracked and considerable 'soot' on the silicone 'cap' on the > tube where the red HV lead entered the tube. I removed the connector, > cleaned the wire and silicone cap, separated the silicone from the lead and > slid some heat shrink tubing over the wire and into the silicone cap. I > used the heat gun to shrink it in place then placed another layer on this. > > Now, the tube seems to work OK (at least observing it for about 48 hours) > with the Ion Pump I stable at about 6 and with no increase, a distinct > change and improvement from before. > > Perhaps I should be satisfied with what I have got but I was wondering what > is under the silicone caps and how to go about removing them to replace the > +3500 VDC and -2500 VDC leads. > > Does anyone have any experience with this? > > Thanks in advance. > > Joe > > > _______________________________________________ > 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.
