The Geiger–Müller counter is a relatively simple tool to measure ionizing radiation. In today post I will present my construction of the Geiger–Müller counter that contains three soviet STS-5 lamp. I've used more than one because that increase sensitivity, that's important for me because I want to measure natural sources of (low) radiation like soil, rocks. I have also in plans building my home radiometric station (it would be part of part of a weather station) connected to the web, so I get the data wherever I am.
The electronic circuit of a Geiger–Müller counter
Waring! The device uses high voltage, this can lead to injury or death when used inappropriately. Don't touch it when power is on, discharge capacitors after use or wait a couple of minutes.