Interesting Took the oscillator board apart last night and found C11 has a cold solder joint. Its the variable cap that tunes the heater. Have not re-soldered it yet as I am having trouble getting enough heat in the area even with a soldering gun to tack the cap back on to the housing. Fortunately I have an even larger gun I will try today. This would indeed explain whi I had variable startups I hope. Especially when tuning the cap. For anyone of interest its 2-20pf johannson type. The manual says 1.5-15. Close enough. Will update later on if I solve the oscillator problem.
On Sat, Jan 22, 2011 at 6:35 AM, Magnus Danielson < mag...@rubidium.dyndns.org> wrote: > On 01/22/2011 04:19 AM, paul swed wrote: > >> Actually there is a paper by Arthur Molenkamp (Spelling wrong) thats quite >> detailed and he seems to have done the same thing I am. You do not need >> the >> heater to start the RB lamp. >> I have found 2 things this evening on the FRS-c. >> >> The oscillator is intermittent and I might guess its the variable tuning >> cap. Boy is that going to be a pain to pull. But bias voltages and xsistor >> behavior look good. >> >> Other item >> Indeed there is a silver dot about 1-2mm in the Rb lamp capsule. I might >> guess this is Magnus's RB that he reheated. I need to peel the glass/mica >> cover off and believe the ampule is released from its holder by breaking >> the >> epoxy that holds it. Really dislike that idea. >> >> Magnus might the mica cover be removed and the capsule heated in place? >> The >> surrounding area seems to be teflon. >> > > Mine was sitting in a metal holder with some white soft material in between > that I didn't identify. Since it needs to handle the temperature of 108 > degrees over long time I figured that it would survive my operation so I > never bothered to pull the glass ampoule out of that grip since it was not > coming loose easily. I haven't been inside a FRS-C so I don't know it looks. > Recall that it is not very high temperatures which is needed. > > Cheers, > Magnus > > > _______________________________________________ > 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.