You are talking about different manufacturers, and also different ages. Best thing I can recommend is to ask for data from members in this group. The big clock I made last year used fifteen IN-1 tubes manufactured in the 1980's, and I had tube failures every few days. I replaced them with Burroughs 6091 tubes manufactured 1963 & 1967, and there have been zero failures or degradation after 1 year. So, even though the IN-1's were about 20 years younger, they were definitely inferior. One would expect that newer manufacturing processes would produce more reliable tubes, but that's not the case here.
Even with the same manufacturer, different tubes will have different lifespans. I have several Burroughs 5031 tubes that appear to have cathode-poisoning because some numerals are not fully illuminated. I cant read many date-codes, but they appear to be ~1963. I have tried and failed to rejuvenate them with higher current. I also have a several dozen Burroughs 5092 tubes, many of which were made in 1963, yet none of them show any signs of degradation. It appears that Burroughs made a substantial improvement with the 5092, though I have not been able to find out what they did. Perhaps it was the addition of mercury, but that is just a guess. -- 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 [email protected]. To post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/e5bc10f4-0797-49e4-b34a-6abb4279de75%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
