Some time ago I’ve won a 63×63 NaI(Tl) crystal for around 80€ at eBay. It is an SDN52 a special crystal designed to be heat and vibration resistant. Let’s build a probe with it and a 76mm photokatode XP2421/SQ PMT
First problem to solve was how to tightly couple this heavy crystal with this PMT? I’ve solved it with the help of my 3D printer: I’ve designed and printed a fitting with TPU that’s a kind of rubber filament material. STL zip file: gasket password: madexp
And now let’s put all togheter.
Finally I’ve soldered in place the dynode chain voltage divider PCB.
After covering the tube with black tape I am ready to test it.
The result is a nice 7.5%-8% FWHM @ Cs137 peak
