I recently had a IN-18 failure in a clock after about 2.5 year operation. Over a (4) day period, the digits in one of the tubes stopped working in PWM dimmed mode. At full brightness, the digits in the affected tube slowly lost percentages of digit coverage to where only portions of each digit would illuminate. At the end of the observed period, the digits in the failing tube went completely dark and even higher voltage on the bench would not illuminate any of the cathodes. The tube date code was 8505.
I am guessing that absent of any other signs of damage, a seal around one of the pins has failed and allowed the tube to leak. It was surprising how quickly it failed and none of the other tubes in the same clock have exhibited any signs of trouble and look as good as the first day of operation. Has anyone experienced similar failures with the IN-18? Is this a typical failure mechanism? Have there been any particular date codes that others have found to be problematic? The tube has been since been replaced and the clock is happy again but curiosity leads me to ask about this experience to the rest of the members of the group. FYI - these tubes have not been rotated since the clock was initially put into operation (no handling). There was never any evidence of cathode poisoning during the operation of the clock. -- 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/4f4d6cf9-6fba-49a6-951a-c83c96f728b1%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
