David Prutchi has just put together a DIY Gamma-Ray Probe using a Philips XP5312/SN photomultiplier tube and a piece of scintillation plastic. A paint can was selected as a nice solid enclosure, the tube and plastic are supported by some foam on the inside to protect them from damage.
“The probe yields a background count of approximately 1,000 counts/minute (cpm) in our lab, and 7,400 cpm from a 137Cs 6.7 µCi exempt source at a distance of 30 cm. The probe’s sensitivity, portability and rugged construction make it an ideal choice for surveying.”
