I've wanted to build a geiger counter in the past but I've always been discouraged because it seems unlikely that I would be able to use it for anything other than maybe testing one or two things in my house like smoke detectors.
You won't get much from the americium in smoke detectors. They're alpha emitters, and ordinary Geiger counters will not detect alphas.
You can build an alpha detector.[1] Even a sheet of paper or a modest distance in air will stop alpha particles, so the detector has to be exposed and the emitter has to be close. A detector inside a glass tube gets nothing from alphas.
You can build an alpha detector.[1] Even a sheet of paper or a modest distance in air will stop alpha particles, so the detector has to be exposed and the emitter has to be close. A detector inside a glass tube gets nothing from alphas.
[1] https://hackaday.com/2022/01/22/detecting-alpha-particles-us...