Hi The “typical life” numbers on the tubes in the various Cesium standards are fairly accurate. Most units that are well cared for “die” when the tube goes out and come back to life when it’s replaced. The tube life dominates the MTBF in this case.
Rb’s are a device that by it’s (possibly unfortunate) physics needs to run hot. The vast majority in service are “miniature” in comparison to a 5071 or a 5065. That drives the temperatures of all the parts up. MTBF on them is very “temperature of use” dependent. They fail for a range of reasons as the parts in them die of “hot old age”. Efratom had some pretty good data on MTBF vs temperature in the LPRO data sheets. The internals of all the designs are similar enough that it likely applies over more than just one design. Temex has a similar data snapshot. I have a sample of the Temex units in front of me as I type this. They died as one would expect - from something other than the bulb. Capacitors, IC’s, crystal drift, board corrosion, being crusted (physical damage), each pop up in the sample. Bob > On Mar 27, 2016, at 7:53 AM, Attila Kinali <att...@kinali.ch> wrote: > > Moin, > > Maybe someone here can help me. > I am looking for data on the reliability of atomic clocks. > I.e. how often and, if possible, how they fail. > > Unfortunately, if I google for reliability then all that pops up > are descriptions of the accuracy and stability of atomic clocks. > If I go for MTBF I only get two papers from the 70s that tackle > the problem in general, without giving any data. > > Does someone know where I could find current data about MTBF and > failure modes of atomic clocks? Given the number of 5071's installed > in labs, there must be at least some data on them.... > > > Attila Kinali > > -- > Reading can seriously damage your ignorance. > -- unknown > _______________________________________________ > 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.