That would appear to be a logical conclusion....I wonder if there's a poor anode connection that separates after heating? Odd for sure....looking forward to your results! They're rare tubes....
Sent from my iPhone > On Nov 24, 2020, at 20:25, Kevin A. <[email protected]> wrote: > > > He picked up the two problem tubes as spares for his black emerald 8971 > clock. The original 6 8971 tubes work just fine in the clock, no matter what > socket they are in. Only when one of these two problem 8971s are popped in > place, does this issue occur. This leads me to believe it is a problem with > the tube rather than the psu or driving circuit. > > I'll ask for a video and will definitely be making measurements once I get a > hold of them for experimenting. > >> On Tue, Nov 24, 2020 at 11:21 PM Nicholas Stock <[email protected]> wrote: >> I know this is a very obvious question, but the power supply your friend is >> using isn't doing something strange instead? That's certainly odd behaviour >> for a nixie... >> >> Nick >> >> Sent from my iPhone >> >>>> On Nov 24, 2020, at 20:14, Kevin A. <[email protected]> wrote: >>>> >>> >>> I will definitely make some measurements once he has a chance to hand them >>> over. From what he told me, the whole tube just self extinguishes during >>> this phenomenon. Very odd. >>> >>>> On Tue, Nov 24, 2020 at 10:53 PM gregebert <[email protected]> wrote: >>>> Can you monitor the voltage and current of the tube while it's running ? I >>>> cant help wondering if higher voltage will keep it on. >>>> >>>> I made my own nixie bench supply which has variable voltage and current, >>>> so I usually set the voltage above 200V, and limit the current to the >>>> datasheet value, which is 4.5 to 6mA per segment for the 8971. >>>> >>>> Do all segments show the same behavior, or just some of them ? >>>> >>>>> On Tuesday, November 24, 2020 at 6:11:58 PM UTC-8 Kevin A. wrote: >>>>> Hi all, >>>>> >>>>> A friend of mine, also purveyor of cold cathode and other unique >>>>> displays, has collected two 8971 nixies that seem to be having an odd >>>>> failure. >>>>> >>>>> When powering the tube on, it ignites normally and begins to operate. >>>>> However, after a period of 30 seconds or so, none of the cathodes can >>>>> stay ignited and they fizzle down into a state of very faint partial >>>>> illumination. >>>>> >>>>> Has anyone experienced this before? The most common failure mode has to >>>>> be outgassing, but the tube is still full of neon as far as I can tell. >>>>> It just does not stay ignited for more than a period of seconds. Can this >>>>> be remedied by applying some kind of high current or high(er) voltage >>>>> pulse the same way cathode poisoning sometimes can? >>>> >>>> -- >>>> 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 view this discussion on the web, visit >>>> https://groups.google.com/d/msgid/neonixie-l/9ca0e0f5-53b7-49c7-a654-a817ca45bfd9n%40googlegroups.com. >>> >>> -- >>> 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 view this discussion on the web, visit >>> https://groups.google.com/d/msgid/neonixie-l/CALcVLK%2Biu8W%2BbKELTYenrkvgMHeGp%3Dxk4_PbrgK3VnQUmKP_jQ%40mail.gmail.com. >> >> -- >> 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 view this discussion on the web, visit >> https://groups.google.com/d/msgid/neonixie-l/63B7ED85-D391-4AC2-9170-274EE3B10DE5%40gmail.com. > > -- > 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 view this discussion on the web, visit > https://groups.google.com/d/msgid/neonixie-l/CALcVLKLDxVKzDu7bAEgLLhBNWEeFbdjKi0NnBwc%2BqeAsWQcs1A%40mail.gmail.com. -- 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 view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/1A8D9BF8-CF05-4B36-AD39-091B15F470F2%40gmail.com.
