Design of door radioactivity contamination detecting system

The door detecting system with industrial PC as its core was designed in order to detect the radioactivity contamination dose of human body, of which the least detecting activity achieved 37kBq (137Cs radioactivity source). The system could accomplish auto-startup via interrupt, and could show overrun and part display through detecting head, shoulders, waists, knees and feet. It discussed the high voltage adjustment of photomultiplier tube, preamplifier and discriminate circuit, detecting system reliability, standardization and anti-jamming in detail. It shows that the detecting system has the feature of stabilization, veracity and high efficiency. (authors)