Tom Thats exactly what I did in building a new oven controller. Figured I would bake some leftover Cs grease off the bottom of the oven. Like you say nothing to loose. I took quite a bit of time in figuring out the levels and it took maybe 60 days. I will guess I am 10 C hotter. At the time I was far more accurate and would need to pull out notes to look at the set temp.... But in magnifying the current meter I could see peaks and dips. Literally through a very sensitive meter with a magnifying glass. Like Pete I run it 3-4 times a year and am amazed when the 2nd harmonic shows up and control takes over etc. I have tinkered with the c field. Maybe I need to get more aggressive.
Regards Paul WB8TSL On Sat, Dec 6, 2014 at 8:49 PM, Tom Van Baak (lab) <t...@leapsecond.com> wrote: > Pete, Paul, > > You can always try increasing the Cs oven temperature. I'm told +10 C will > double the beam current -- and half the life. But my my, hey hey sometimes > it's better to burn out than fade away. > > /tvb (i5s) > > > On Dec 6, 2014, at 5:25 PM, Pete Lancashire <p...@petelancashire.com> > wrote: > > > > Paul and I have tubes that most would consider dead. Mine is not far > > behind. I fire it up about 3 to 4 times a year if anything to keep it > > pumped down. I can still get the correct peak with the internal meter but > > it is getting harder each time. > >> On Dec 6, 2014 11:16 AM, "paul swed" <paulsw...@gmail.com> wrote: > >> > >> All good answers with a good tube and enough current to read on the > meter. > >> But I am working at the very limit of the Cs fumes. There is current, > about > >> .5 to 1 tick mark on the meter of a 5061 using a 5060 tube. > >> Thats the challenge on a very eol tube. > >> Regards > >> Paul. > >> > >> On Sat, Dec 6, 2014 at 1:56 PM, Magnus Danielson < > >> mag...@rubidium.dyndns.org > >>> wrote: > >> > >>> Tom, > >>> > >>>> On 12/06/2014 06:04 PM, Tom Van Baak wrote: > >>>> > >>>> Paul, > >>>> > >>>> There are 7 peaks total, about 40 kHz apart (on my 5061A). If you're > >>>> talking about just the central peak, there are two smaller peaks on > >> either > >>>> side, about 1 kHz apart. The exact value depends on internal magnetic > >>>> field, which is specific to each beam tube design. > >>>> > >>>> For some measurements of all the peaks, have a look at: > >>>> http://leapsecond.com/pages/cspeak/ > >>> > >>> These are the 7 Zeeman pedestals, and on top of them you have the > Ramsay > >>> fringes. You can indeed lock onto the wrong Ramsey-fringe, but they too > >>> have amplitude differences. For a normal tube, they are quite > >> significant, > >>> but if you look at the Ramsay fringes on the NIST-F1, they are much > >> denser > >>> and looses amplitude much slower, so you need to pay more details of > >> which > >>> fringe you use. The density of the Ramsay fringes is due to the > >> observation > >>> time, which has been one of the driving forces to develop hydrogen > masers > >>> and cesium fountains, but for a simple cesium tube, it's a few dm of > >>> distance and the average speed of the cesium steam. > >>> > >>> You can play with the C-field in addition to playing with peaks: > >>>> http://leapsecond.com/images/cfield.gif (578 x 4610 pixels) > >>> > >>> Which is a good illustration. It would be good. > >>> > >>> For more details search the archives for the word Zeeman. For example: > >>>> https://www.febo.com/pipermail/time-nuts/2005-April/018171.html > >>>> > >>>> A nice description from hp how a cesium beam standard works: > >>>> http://leapsecond.com/museum/hp5062c/theory.htm > >>> > >>> Do check the FTS-4065C manual as I just uploaded. Good complementary > >>> information. > >>> > >>> 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. > > _______________________________________________ > > 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. > _______________________________________________ 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.