Hi, Thanks for all the comments!
Will - Not entirely sure about the lifetime - I suspect it's something to do with the large cathode area I've got (as a result of the way I made the cathode form steel sheet rather than wire). I guess the lifetime could be improved a lot by using neon (smaller atom mass, hence less sputtering) but I'd need to get hold of some first ;-) Marcin/John - I've sent you a pm regarding the tubes Yes, I saw Claude Paillard's video a while back and it was truly inspiring! The induction heating bakeout is probably essential for high-vacuum tubes (triodes etc) - I don't know about higher-pressure tubes like cold cathode devices. I was hoping that it wouldn't be so critical. That's a good point about the gas pressure - bit counter intuitive! You'd think that lower pressure would be better because you've got fewer atoms hitting the surface, but of course they'd be striking at higher energies. A nixie book did say that it is best to use the highest pressure possible, to avoid sputtering (it also gives you a good reservoir of gas). Trouble is, you often need to lower the pressure in order to get a uniform cathode glow at a reasonable tube current. Mercury seems to have a huge impact on lifetime as well - Bylander's book "Electronic Displays" has a graph of lifetime with and without mercury, and mercury addition is something like 20 times better. But I'd rather not be messing around with mercury! Cheers, Lindsay -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
