Hello.
I was wrong on the leak direction, indeed. I did further experiments with
the couple of tubes that react to the neon tester (HVAC source applied to
one pin, and holding the tube with the other hand).
I could pile up power supplies to just below 700V and digits still don't
light fully. Given
That's pretty cool that it somewhat lights up. However I think that you're
mistaken in your assumption that the neon has escaped, leaving only argon
in there. The gas mixture in a Nixie tube is at a very low pressure, so my
guess is that atmospheric air has leaked into the tube, thus increasing
I still think the tube has leaked. 600V is a lot of voltage, and it's going
to get pretty warm at 9mA.
>From Paschen's curve, the ionization voltage is at a minimum at a certain
pressure, around a few mBar. At pressures above AND below that point, the
ionization voltage increases. As a tube lea
