Quote Originally Posted by Dave View Post
I also see the same mistake in the 24 hour mode where you say if hour = 25 then hour = 1. 24 hour time starts from 00:00 to 23:59.

BTW, Nice PCB. I have some RCA Numitrons with 9 pin sockets. I was thinking about using them for a clock but the lifetime of the tubes isn't very good so I built a couple of nixie clocks with VM1000 tubes. Attacked is a photo.

Dave Purola,
Dave, nice looking clock as well. The boards came from a place called OSH Park. They run batches of boards so the average time is about two weeks but the quality and price is great. Purple boards seem to be their trademark. If you are worried about longevity of the numitrons you can use the TLC5916 or similar chips from TI. They are meant for driving LEDs and have an adjustable constant current feature. For some reason the minute digits were both dimmer than the hours and needed slightly different resistor values.