28 Oct
1998
28 Oct
'98
12:19 p.m.
Don't they run on 170 volts or somesuch wild
figure???
A nixie tube is basically a neon bulb. It turns out that if you drive a
neon bulb from DC, then the cathode appears to glow, and the anode
doesn't. A nixie tube has a number of cathodes in the shape of the
required symbols (often, but not always, 0-9), and a mesh anode. Being a neon bulb, it needs a current-limited HV
supply to run it.
Typically a 200V-ish supply with A suitable series resistor.
I'll have to rig up some kind of ladder network, I guess. I have a board
out of an ancient calculator with 9 or 10 Nixie tubes (and a neon bulb
for the '-' sign). I've always wanted to fire it up, but never had the
time to build some kind of high-voltage BCD driver. This sounds like a job
for a PIC, a kind of serial to Nixie driver. I could always drive it with
an ancient UART (the kind that didn't need a CPU) and a pile ot TTL, but
I think the PIC could keep the part count low.
-ethan