Geiger-Muller Counter with Nixie Display

Possibly my most complete electronics project?

Man, I’m proud of this one. It’s actually finished, has a whole host of different hand-made parts and it didn’t even take all that long. Or didn’t feel like it anyway.

What’s the secret?

Mini projects! I thought of every aspect of it as a project in its own right - e.g. providing a high voltage for the nixie tubes, their driver circuitry and programming, the laser cut case, the handles, etc etc.

Small projects that could each be completed over the course of an evening or two - giving that sweet brief dopamine hit we all crave.

Features

• Nixie IN-1 tubes - produced around 1980. Such a gorgeous neon flame that doesn’t translate in photographs
• On/off switch produced in 1970s Britain - given me as a small child by my late grandfather. I’m sure he would have appreciated the usage here!
• Laser cut case, with oak-veneer panel for the front and acrylic on the back. The raster etching didn’t turn out great, but an important lesson learnt
• Retro style handles - hand made by hammering some tube and cutting thread with a die. New technique to me, again not great but I’m learning and they feel fantastic to grab
• Geiger counter kit which is simply hooked up to an Arduino to do the thinking
• Lipo power of course

Technically perhaps not the most complex project, or even a particularly interesting concept but there were a heck of a lot of firsts for me so that’s why I went for it and yes, before you ask, I did shock myself with the high voltage supply (180V but it was only a little ouchy).

Curios

Interestingly (to me) the Nixie tubes are still dead cheap. They’re New Old Stock (NOS) and produced decades ago but they must have millions stored away.

THE SOCKETS however, are ridiculously expensive. We’re talking £15+ each, so screw that. I built my own little socket wires using crimp connectors. It was the ballest of ballaches but I’m not waiting around for an eastern European import at that price. That said, for other more popular tubes (IN-14 for example) it’s cheap. I just liked these big fat old ones, despite their terrible lifespan of 1000h.

Oh and the background radiation of course. It ticks over every two or three seconds which, yeah I expected it to be less I think.. ah well, the planet’s screwed.