We prepared a short note on how to build a dynode voltage divider network for inexpensive surplus XP2422/SN photomultiplier tubes. The XP2422/SN PMT is especially suited for gamma-ray spectral analysis when coupled to a NaI(Tl) scintillation crystal because of its high pulse-height resolution (PHR). The XP2422/SN is available from Sphere Research in Canada.
Scionix in The Netherlands has taken advantage of the recent development of miniature mesh-type dynode photomultiplier tubes to construct small-diameter scintillation probes. Scionix’s miniature probes incorporate one of those PMTs, a NaI(Tl) scintillation crystal, and a built-in dynode voltage divider. Connection to the probe is made through a miniature high-voltage locking coaxial connector. Finding a mating connector is the main
Many surplus scintillation probes have a single connector through which the PMT is fed with high voltage and the anode signal is output. However, this may require an external “Bias-T” (a high voltage / signal splitter) to connect the probe to a high-voltage power supply that is separate from the PMT amplifier/processor.
Simple d.i.y. Low-Pass Filter for Interfacing PMT Amplifier to PC Sound Card (Used with Free “Pulse Recorder and Analyser” Software MCA)
Figure 34 in the book shows the schematic diagram for our photomultiplier tube (PMT) signal processing circuit has an analog output that is suitable for use with a sound-card-based multichannel pulse-height analyzer (MCA). However, if you already have a commercial scintillation processor that you would like to use with PRA, then you will somehow need to
Military DT-590A/PDR-56 “x-ray” probes are widely available in the surplus market. They were meant to be used with the military Radiac Set AN/PDR-56, which is a portable scintillation-type instrument used for detection of plutonium-239 contamination. In addition to emitting 5.1 MeV alpha particles, Plutonium-239 also emits gamma rays in the energy range of 14 to 21
An amateur-use open-source gamma spectrum analyzer is being developed by members of the GeigerCounterEnthusiast (GCE) Yahoo Group. This multichannel analyzer (MCA) is based on the STM32F103VBT6 microcontroller. It displays spectra on a color LCD. To access the design files (and hopefully to participate in the development) you will need to join the GammaSpectrometry Yahoo Group
Some time ago I was developing a medical instrument which required histogramming, which got me in the mood to retake my own PIC MCA project(http://home.comcast.net/~prutchi/index_files/scint.htm ). I used the variable RAM in the microcontroller (16F877), so I limited the number of channels to 95 and let the histogram run until some channel reaches 240 counts (the