Here’s an entry in the Open 7400 Logic conpetition: A nixie tube clock.
My entry for the competiton is a nixie tube clock where all the logic is in 4000 series chips (and the tube drivers are 7400 series!).
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Here’s an entry in the Open 7400 Logic conpetition: A nixie tube clock.
My entry for the competiton is a nixie tube clock where all the logic is in 4000 series chips (and the tube drivers are 7400 series!).
Very interesting.
I must have forgotten about 74 vs. 4000 series and their relative advantages, because I would assume that the 74 series are limited to 5V and thus might have more trouble driving the tubes, whereas 4000 series logic can operate easily on higher voltages (but not 180V). Then again, I suppose the 74 series can sink more current while the 4000 series will use less power (thus draining the backup power more slowly, as mentioned in the project description).
It’s impressive that the 74141 can withstand 60V on its output pins and the 5V supply does not pose a limitation. The current is less than 7 mA, though, which is very different than what might be needed for an equivalent LED clock.