iPhone geiger counter

I built the first prototype of an iPhone geiger counter.

It uses a russian SI-29BG geiger tube that I got from ebay for 20 Euros:

These tubes need a current of 400 volts to work, so I looked for a circuit that accomplishes that on a small area and uses standard components.

I found this: Geiger circuit

After adapting it a bit, so it can output the signal to the iPhones audio jack I tested it on a breadboard:

It worked. Then I spent a long time fitting it on a 25x55mm board with a one-layer routing I milled a pcb from that.

Next thing was the case. I designed it in FreeCAD:

Milled that one from a POM plastic block on the cnc mill of the attraktor hackerspace in hamburg (best place in the world!), turned out OK:

Then I put my stuff in it:

The app is called ‘geiger bot’ and it’s available for free on the appstore.

I’m currently working on Version2.0 that won’t have a physical switch, a smaller battery and is 5mm shorter. When that is done I’ll release everything that’s needed to build one yourself here. I could also make a small series of cases if enough people want one.