Nuclear Decay module, 50x200 mm, with one pot, two jacks, and a window showing the Geiger tube with a spacer above it for hanging a source

This is my version of TimMJN’s Geiger counter module . It uses a commercially available Geiger counter PCB along with an auxiliary circuit on protoboard to create a decay envelope whenever the Geiger counter fires. I added a trigger output as well, and a window on the front panel to allow viewing the Geiger tube — and to reduce the amount of material particles have to get through, at least from that direction. There is a spacer sticking out above the window, for hanging a radioactive source.