Hi Chris,
The numitrons are driven by a 4511 decoder, and according to their data sheets the max. output at that voltage is 4.1 V, so that is well within specification for the tube. Yes, I agree, lowering the voltage even further should increase lifespan. Bill v From: [email protected] <[email protected]> On Behalf Of Chris Sent: Saturday, March 04, 2023 8:19 AM To: neonixie-l <[email protected]> Subject: [neonixie-l] Re: IV-9 numitron lifespan Hi, While i am not sure for the IV9 numitrons have a look at the DA2300 lifetime expectancy, <https://www.dos4ever.com/numitron/lifenew.gif> Basically reducing the voltage increases the life expectancy exponentially. So i usually run my numitrons at 4.5V or lower and have had no issues so far. On Friday, March 3, 2023 at 8:05:48 PM UTC+1 [email protected] <mailto:[email protected]> wrote: I seem to recall there was some discussion on the life expectancy of IV-9 numitrons some time ago. In 2015 I built a number of clocks with these tubes, and they started failing last year. The clock in the picture is on my bench now, the three good tubes were replaced in November last year. So today all 6 tubes will be replaced. I have replaced all 6 tubes on a few other clocks also. One or more segments will no longer light up, and I do not see any blackening of the glass tube (The black you see in the picture is my permanent marker, s I will not replace the wrong tube when I disconnect the power). The tubes are driven directly from a 4511 chip on a 5V power line. There does not seem to be any order in which they fail, so I do not have the feeling that any of the tubes are significantly impacted by thermal stresses from flashing on and off. I would say based on my experience with them, the expected lifespan is about 7 years of continues use. Bill v -- 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] <mailto:[email protected]> . To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/81b5b7e6-d476-4b83-9a8e-c9d6cc468db9n%40googlegroups.com <https://groups.google.com/d/msgid/neonixie-l/81b5b7e6-d476-4b83-9a8e-c9d6cc468db9n%40googlegroups.com?utm_medium=email&utm_source=footer> . -- 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/00a901d94ea0%247ee82fe0%247cb88fa0%24%40gmail.com.
