At first, the unused digits begin to show poisoning effect (e.g. digits 6-9) of the first minute tube. Sure, that's nothing strange as they never light up.
Then the other digits get dark spots with gets worse and worse until all digits are black. I will now change the anode resistors to values that the tubes draw ~6mA instead of only 4.5mA. Because, as already mentioned here, it's not necessarily good for the tubes to be driven with very low current. Am Dienstag, 3. Oktober 2017 18:05:06 UTC+2 schrieb gregebert: > > 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 [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/f90930d5-9eab-4012-826a-a16e6bd49b95%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
