Hi Based on several replacements on a “high performance” 5071 …. 6 to 7 years of 24/7/365 seems to be about the point things start to get flakey. Maybe not dead, but crazy enough that it lets you know it needs a new tube ( = ADEV is not even close to what it should be ..).
Cost several years back for the swap out was right at $40K. The process included hazmat shipping silly nonsense. That part delayed the process by almost 2 months. Bob > On Jun 30, 2019, at 4:55 PM, Tom Van Baak <[email protected]> wrote: > > I'm pretty sure you can still buy a new Cs tube for a hp 5071A. But the price > is several tens of thousands. I've not found anyone selling replacement tubes > for all the older Cs standards. Treat it like a ballpoint pen. It will end > some day and you can't refill it. Worse, you can't really tell how much "ink" > is left in the tube. Still, it's easy to swap in a new or used tube if you > have it. > > On eBay stay away from Cs standards with the "high performance" option. Yes, > these tubes give you ~2x better stability -- but at the cost of ~4x the beam > current and thus maybe a quarter of the lifetime. I haven't seen any recent > data but you can roughly expect a high-performance tube to last 7 to 10 years > if used full-time and if there are no other defects. A standard tube might > last 20 to 25 years if used full-time and there are no other defects. > > So it's not as bad as you think. And I would never use the word > "disappointing". Come on, decades of physics research, not to mention a few > Nobel prizes, turned a room-sized atomic physics laboratory into a compact > 19" unit that fits on your desk. And its portable. > > The more you study the history of timekeeping and the more you learn about > how cesium standards work the more you will be absolutely amazed at what it > is that you own. Treat it with great awe and respect. Like others have said, > you don't have to run it 24x7 and if its working well today, it could easily > outlast you. Now that's the disappointing part... > > /tvb > > > On 6/29/2019 7:46 AM, Taka Kamiya via time-nuts wrote: >> I paid very little to purchase, so it's not a big deal from financial stand >> point, but it's disappointing that once it's done, it's done. >> By recommendation, I am keeping it mostly off and turn it on few days >> earlier of anticipated use, mostly to calibrate/verify something else. My >> usual reference is GPSDO and Rubidium which are redundant and always on. >> >> --------------------------------------- >> (Mr.) Taka Kamiya >> I'm stuck in a wormhole.... Hello, worms! >> >> On Friday, June 28, 2019, 5:00:25 PM EDT, Taka Kamiya via time-nuts >> <[email protected]> wrote: >> I have a Datum FTS 4040A. I believe the tube is original but it is still >> locking and staying in lock just fine. I don't know for how long. In an >> event where tube goes soft/dead, replacing it with factory new replacement >> part is out of question for cost. Are there any refurbished tubes available >> from anyone? >> >> --------------------------------------- >> (Mr.) Taka Kamiya >> I'm stuck in a wormhole.... Hello, worms! >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
