A spotter's guide to the SBM-20 Geiger counter tube
My Geiger Counter kit will accommodate the STS-5 and all of the SBM-20 variants shown. The SBM-20U requires a short jumper wire to connect the positive terminal to the PCB. I recommend using an alligator clip or wrapping a wire around the terminal to avoid compromising the glass to metal seal with the heat of the solder.