I think the survivability of GM tubes is relatively low due to their thin soft glass construction (window). There have been several variations developed in more recent times eg Elektor has their GM detector on special this week see www.elektor.com/mightyohm-geiger-counter-kit-bundle Previously they had a circuit using LEDs as the actual radiation detectors. Cheers, D
im wanting an older style, and have the parts needed to repair one, GM tubes are readily available. i have some exe russian gm tubes, and im building a basic unit with Arduino. but im really looking for an old analog set up, like the old civil defence models from the cold war era.
I've only ever seen one of these older GM style ratemeter sets on trademe and that was at some mind blowing price (think it was $600) - presumably some must still be around but seem quite uncommon. However Practical Electronics around 1965 or 66 had designs for building them - you can find scanned copies of this mag on US sites by googling it. Practical Wireless may have also have had plans.