One of the most requested features on my clock was the separator, so I have decided to add two INS-1. Once I got my tubes, I tested large batch of them and discovered that some of the tubes start to flicker after about 15 minutes. My first thought was that those tubes are going bad, after all, they are old and the quality is... well, just look at the lens with magnifying glass. Since this "effect" is similar to flicker flame, where low current makes neon unstable, I figured I have to increase the current. My default was 0.6mA (220K @ 180V,) so I bumped it to 0.75mA (180K.) That did not help, it made it little worst I think, so I figured that's not it. I tried to go the other way and decreased the current to 0.3mA (470K) and then to 0.15mA (1M.) That helped, flicker became slower, which might be unnoticeable when tube is used in a separator. Another advantage was that the glow was not as strong as @0.6mA and now it matched glow of other Nixies (digits.)
Just for fun, I reversed polarity. Flicker was gone and the glow was brighter. However, I will not suggest using them in reverse. Then I decided to do an experiment. I connected flickering tube in reverse without current limiting resistor (however, my power supply limits current to 15mA.) The tube started flashing white, blue, red for about 2-3 seconds and then turned bright orange (normal operation but very bright.) I kept it on for another 2 -3 seconds and turned it off. Now, when connected the right way, tube no longer flickers. I did that with several tubes and they all became flicker free (kept them on for couple of hours.) Only one tube started flickering again, but the flicker goes away after several seconds (flicker starts slow, then faster, and then stops.) I will keep them on for few days and report back. -- 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/5db50a19-d85d-4aef-a303-e876534d9572%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
