Can you do some bench-testing to see if the segments fully light with a bit more voltage ? I collected current-voltage (I-V) data on all my 7971's so I can check them for aging effects.
On Sunday, October 8, 2023 at 6:01:55 AM UTC-7 [email protected] wrote: > Hello Jim, > > If you have a source of UV-light, that will do a good job. > Maybe an UV-Led beneath the tube will do the trick.... > > BR/ > Guus > > Op 07-10-2023 19:26 CEST schreef Jim KO5V <[email protected]>: > > > > I have a B7971 that doesn't want to light up - the ends of some segments > will glow, but none will illuminate along their entire length. I have had > tubes in the past that were probably a bit gassy, and they cleaned up after > running for a few minutes to a few hours. > > So, I put it into the "10 second" position of my Mod 6 clock, and ran it > over night with no improvement. However after I had been up an hour or so, > I noticed that the tube's segments were lighting up along about 3/4 of > their lengths, and also that the low morning sun was shining on the clock. > This state lasted for as long as the sunlight was on the tube - sometime > after light moved off of the clock, the tube went back to it's wounded > state. > > This morning I watched as the sunlight moved toward the clock, and as soon > as the light hit the clock, the tube immediately recovered, and performed > like it did yesterday. However, that state lasted for about 3-1/2 hours > after the sunlight moved away. I then shined a flashlight on the tube, and > it recovered as long as the light was there. > > I guess this is some kind of photo-voltaic effect. I have a bit of > education in basic physics (for engineering), and this baffles me - but > it's cool! > > I have a reading lamp that puts out a full spectrum, so I will put that on > the clock today and see what happens. I may also set up a test to run the > tube at a bit higher voltage (180-ish V). It may never recover completely, > but I think this is a fun exercise. > > Anyway, and ideas are welcome. I may not be able to save the tube, but I > might actually learn something. Thanks. Jim > > > > -- > 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/d2784c4a-c76f-4ae6-b0b1-86f14185bb22n%40googlegroups.com > > <https://groups.google.com/d/msgid/neonixie-l/d2784c4a-c76f-4ae6-b0b1-86f14185bb22n%40googlegroups.com?utm_medium=email&utm_source=footer>. > > > > -- 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/3823a1c1-e56c-4310-969f-255a9e2da5fcn%40googlegroups.com.
