Primary Testing Performance of Designed Wide-dynamic Range Gamma Ray Dosimeter Based on Double GM Counters

For locating and grasping the lost gamma ray source with a robot in a nuclear accident, a gamma ray dosimeter based on double GM (GeigerMüller) counters (ZP1321, ZP1301) was primarily designed with widedynamic range. The frontend analogue circuits for detector signal processing and the microcontrollerbased detector data processing and transmission programs were designed and tested primarily with 137Cs gamma ray source. The main influence factors on the designed dosimeter output signal were measured and analyzed. The primary experimental results show that the designed gamma ray dosimeter without shielding case can detect gamma ray radiation sources online successfully.