Are all numerals inside the tube dying, or just pieces of some numerals. Cathode poisoning should only affect seldom-used numerals.
If all of the numerals in a specific tube are failing, I can think of 2 causes. #1 would be a leak. Check for cracks around the pin base. Are the tubes snug/difficult to insert/remove from the socket ? If so, there could be pin-stress that's breaking the glass-seal. #2 would be a power-supply issue. Can you bench-test your tubes at a higher voltage ? I recall my IN-18's were glowing nicely around 140V; the ionization voltage is a bit difficult to measure, and I was measuring around 165-175 volts. It's a long-shot, but you may have some tubes that need a few more volts to ionize as they age. My IN-18 clock has 14 tubes to display date and time (MM.DD.YYYY HH:MM:SS format) . The tubes on the left are basically static, which is a bad thing to do. Every night, I run a depoisoning routine for 1 hour to display all numerals on the static tubes and I see no signs of poisoning on any tube after almost 2 years of usage. The display is on for about 16 hours per day. -- 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 neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/9bb3869b-4465-4b67-8ec7-22406058f0e1%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
