I have the Radiacode 102 and I've been pretty happy with it! I use it when I travel. It turns out the background radiation in Madrid is twice as high as in Amsterdam! ๐
Here are some images and a spectrum I collected of some radium-containing clocks:
After getting the Radiacode 102 I became very curious with the measurement itself, and I have built some spectrometers since then.
This one I made using a photomultiplier tube kit from e-bay, a PMT driver from RH Electronics, and a 192 KHz sound card off Ali Express:
There is also the OpenGamma Detector Project. This one I started building but I still haven't gotten it to work perfectly.
If anyone needs help sourcing parts, wiring a device, or writing the peak analyzer program, just send me a message! The Radiacode 103 is quite a good option, though.