On Thursday, June 2, 2016 at 11:43:26 PM UTC-7, Jeff Walton wrote: > > *From:* neonixie-l@googlegroups.com [mailto:neonixie-l@googlegroups.com] *On > Behalf Of *Forfanatic Tsai > *Sent:* Friday, June 03, 2016 1:08 AM > *To:* neonixie-l > *Subject:* [neonixie-l] Relocate tubes on single clock > >> Will you relocate tubes on a clock? like switch second tubes with hour >> tubes for balancing life time. Or just left them there until they fails? >> > > > I would have no problem moving them around (that’s my comfort level) but > the cathode poisoning prevention routines are supposed to help prolong the > usable life of the tubes. Even within a single tube, you might normally > observe small variations. You only run the risk of damaging the pin seals > to the tubes by physically moving them around. Careful handling and > straight pins will reduce the risk. >
I seem to recall discussion in the old Yahoo NEONIXIE-L of a U.S. Army report that scheduled monthly testing of in-service vacuum tubes (necessitating their removal from equipment) caused such a service-wide statistical increase in tube failures that the practice was largely abandoned; for most purposes it was deemed not worth the cost to have them fail more often (or be discovered to be about to fail) during scheduled downtime, than to simply let them fail whenever they happened to do so. I searched in the archive some but couldn't find the thread... does groups.io have an "Advanced Search" feature? > On Wednesday, June 8, 2016 at 8:37:03 AM UTC-7, Alic wrote: > I thought that there was actually an exchange of matter between the > cathodes going both ways when all the cathodes are on alternatively. > Which means that if only 1 or 2 cathodes are used, theses cathodes erode > faster. There is definitely an exchange of matter, but that may or may not be a good thing. In mercury-doped tubes, presumably it is a good thing to return some mercury to the "off" cathodes from the presently "on" cathode, but I'm not sure the equivalent is true for non-mercury tubes. -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/ac2126b0-af3f-4201-af02-0d12df6468c4%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
