On Thursday, August 11, 2022 at 9:53:33 PM UTC-7 Kevin A. wrote: > I feel like PIRs are a must on most nix clocks. Why burn up tubes when no > one is around to enjoy the glow? Seems like a total waste. > > This may be detrimental in some cases. For example, the B9771 spec sheet projects a lifetime of 50k hours, which is obviously a conservative estimate. In my limited experience with 18 tubes in 3 clocks, the tubes have been used for over 350k hours (45+ years) with no failures; there has been some slight darkening of the glass (probably because the tubes were over driven compared to the spec sheet recommendations), but there are no signs of any imminent med for replacement. The parts that have failed included power transformers, filter capacitors, LSI clock chips, and HV driver transistors on the anode side. Based on this, it would not surprise me if the PIR device proved less reliable and needed replacement before the tubes would die a natural death.
-- 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/a6e05969-f819-4ce7-b7c6-d849847df560n%40googlegroups.com.
