We modified a surplus Civil Defense V-700 radiation survey meter made by Electro Neutronics Inc. (Model 6-b) into a very capable radiation counter capable of working with both Geiger-Müller and PMT scintillation probes. We modified the front panel to accommodate the new switches, connectors, and panel light. In addition, we placed a Veeder-Root count totalizer module on the side of the box. The new electronic components, including a Zener diode stack and a PMT preamplifier are wired directly to the original printed circuit board.
The following file shows each step in the modification process with large color pictures and expanded diagrams
Click here for tutorial in pdf format
Click here for datasheet of Veeder-Root totalizer module
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