Claude, The main loop of a Rubidium oscillator is composed from a Lamp and a light sensor . The sensor detect the light level and the relative voltage is present on the external connector of the Rubidium (see the manual of yours). During the life of the Rubidium, some lamp particles obscure the internal side of the lamp glass. Consequently decreases the light intensity . Monitoring the voltage of the sensor you can understand the state of life of the lamp. You can see in the Rubidium Manual the voltage range for the correct working conditions. Other measurement can detect the end of life before the the unlock of the Rubidium is to measure the phase noise of the 10 MHz output signal. This Noise will increase with the end of the life of the Lamp. Th do this measurement sophisticate intruments are needed. I suggest to monitor the voltage as previously described.
Hope to contribute to help you, Luciano www.timeok.it On Sun, Apr 21, 2013 at 3:11 PM, Claude Fender <lab...@yahoo.fr> wrote: > Thanks for your answer. > > Actually, I use a 5334B counter locked on a GPS to record the output of > the rubidium 24/7, with gate times of 10s and 100s . > The measurements are constants between 10,000,000.002 and 10,000,000.004 > Hz, the resolution is 1 mHz for 10s and 0.1 mHz for 100s. I have not enough > records to see a drift. > > In your opinion, with this method, when the Rb will become older, I will > see some short "jumps" in frequency from time to time ? > > I agree this is an heavy method compared to your blink-ometer but I am > still learning ! > > Claude > > > > > ________________________________ > De : paul swed <paulsw...@gmail.com> > À : Claude Fender <lab...@yahoo.fr>; Discussion of precise time and > frequency measurement <time-nuts@febo.com> > Envoyé le : Samedi 20 avril 2013 17h58 > Objet : Re: [time-nuts] How dies a Rubidium ? > > > > In my experience with numbers of less expensive cel tower pulls, they > blink out and re-ignite and then relock this is infrequent. But occurs more > and more often. If RB is suspected of going to the darkside, I use the > blink-ometer to catch this. > > > What the heck is a blink-ometer? > Simply one of those little pedometer counters that I have tapped into and > through a opto coupler allow the blink to trigger a count. Happy to sell > you one for $199 plus shipping and if you act now will include another for > postage and handling.... > > The other clue is the lamp voltage. This is a relative clue if your unit > even gives you access to it. The FRS start at 9 or so volts and seem to > start to blink about 3. Its relative and your milage will vary. > Regards > Paul > WB8TSL > > > > On Sat, Apr 20, 2013 at 5:13 AM, Claude Fender <lab...@yahoo.fr> wrote: > > Hi, > > > >I would like to know if there is a way to know if a Rubidium is at his > end of life or not : when it stops working, does this happen suddenly or > are there percursory symptoms ? > >I am looking fora method that does not need to open the case (I have a > 5680A and I am waiting a Racal Dana). > > > >Thanks for your advices ! > > > >Claude > >_______________________________________________ > >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. > -- Luciano Timeok visit : www.timeok.it _______________________________________________ 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.
