Still wondering if the CPP process can also be used to clean a contaminated tube over time as opposed to just trying to prevent poisoning. I’m wondering about applying a higher power pulse for a short duty cycle so that the CPP goes a little beyond normal operation. A cathode can poison even when the tube is in storage due to impurities in the gas and all cathodes are contaminated in normal operation. Regular CPP process assumes that normal operation of the cathode will drive off any impurities and we all know that in the real world even at nominal currents, cathodes still get contaminated even when we think that all of the digits are being operated.
In the case of a high speed CPP process, a short, higher current pulse of short duration may be able to clean a mild buildup on the cathode surface. Again, all cathodes are contaminated by the operation of another “ON” cathode. Your process does offer an opportunity to sequentially hit each cathode with a pulse that is different than normal operation and may provide a cumulative effect over time to actually clean cathodes without the need for long-term and sustained overdriving of a single cathode. It potentially could be done without a significant impact on the useful life of a tube in normal operation. Rather than thinking of it as prevention, your technique might offer a way to mildly clean and prevent. It actually does look interesting in the video… Jeff From: 'Spirit's lab' via neonixie-l [mailto:neonixie-l@googlegroups.com] Sent: Wednesday, March 7, 2018 1:19 PM To: neonixie-l Subject: [neonixie-l] Re: An investigation into better ways to do cathode poisoning prevention - 1000 fps slow motion included @Jeff The heating should only be enough to prevent cathode poisoning starting with a healthy(ideally new) tube. I seriously doubt it would do anything to fix already existing cathode poisoning. It's driven using the same, standard current(4-6mA for an IN-18) for normal operation. To fix existing cathode poisoning you do indeed have to seriously overdrive the tube and keep every cathode needed on, sequentially. @Allen I made this with the intent of running it more often - a few seconds every 5, 10, maybe 15 minutes. If cycling on every digit change, it could be quite distracting, because the perceived brightness of the tube increases dramatically, and it would just keep flashing. Doing it every 30 to 60 seconds should be about the minimum time period acceptable, but it really depends on your tastes. -- 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 email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/6c8a3859-79f1-43d2-acdc-dbbb9e143f02%40googlegroups.com <https://groups.google.com/d/msgid/neonixie-l/6c8a3859-79f1-43d2-acdc-dbbb9e143f02%40googlegroups.com?utm_medium=email&utm_source=footer> . For more options, visit https://groups.google.com/d/optout. -- 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/5aa06fea.1236240a.5268c.8770%40mx.google.com. For more options, visit https://groups.google.com/d/optout.
