For those of you who did your own poison-prevention algorithms, are you trying to run all cathodes for the same amount of time, or do you just activate the 'dead' ones for a few minutes each day when nobody is watching the clock ?
Thanks to the 'Tomorrowland' movie, I'm making my first IN-18 clock because my wife likes the larger digits. All of my previous clocks have been Burroughs or Sperry devices. I plan to build a 10-tube clock with hours:minutes:seconds month:day. Swapping date & time doesn't solve the poisoning risk for us 'backward-date' folks in the USA where "03/07" means March 7, rather than July 3. Going to 12 or 14 tubes so I can display the year doesn't seem necessary to me. Then again, this *is* a nixie clock, so by definition the whole contraption isn't "necessary"...... The tens-hours & and tens-month are probably the biggest problems (especially in 12-hour time format); I'm not worried about the slight imbalance in runtime that units-hours, units-days, and units-months will have. I'll be using direct-drive, at 5mA per tube (spec is 4-8mA). I plan to make the drive-current adjustable, so when I de-poison digits they could run at a higher current but I doubt I will go more than 10mA. I'm looking into driving dark cathodes from the anode supply (basically a push-pull driver for each cathode), but that all depends upon how much PCB area and money I'm willing to spend on it. Putting pullup resistors on all cathodes, then driving one low, is a big waste of energy and generates unwanted heat. Other suggestions I can use to maximize tube-life ? BTW, the first batch of IN-18's I bought are 1991 date-code, and they cost quite a bit more. I've seen cheaper IN-18's for sale from the early 1980's that I've read have reliability issues. -- 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/7e82c90a-bb58-41ca-b11d-5a57abee37b6%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
