[Swlug] DIY Geiger counter

[Rhys Sage]

I've put the circuit  together pretty much as in the diagram in the nuclear research document. And I'm getting a background ripple. It's not quite the 50-100 clicks a minute that I was expecting from what I'd read. I had to substitute the 10M resistor for 1M. I have tried other values. I tried 560K instead of the 1M and 5.6K instead of the 10K resistor just to see what would happen. The capacitor is spot on at 100nf. Nothing made enough of a difference. Though I can see the ripple on the oscilloscope, I doubt I will be able to read it on an Arduino. I reckon if I can see background radiation on the Arduino then I can count excess radiation.

The only differences are the voltage from the Buck converter is 4.7v so the circuit runs from 4.7v not 27v and I'm using a photodiode and not a GM tube.

Rhys Sage
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