An Improved Polarity Coincidence Detector

摘要

A Polarity Coincidence Detector has been constructed with increased sensitivity and sufficient threshold stability to allow integration times in excess of 1,000,000. The system uses sampling at four phase locations, thereby increasing the signal count and shortening the integration time for a given accuracy by eliminating the necessity for measuring the noise separately. The modulation frequency can be varied between 50Hz and 50 kHz without adjusting the location of the sampling pulses. Solid state circuitry is used throughout the system. The straight counters are replaced by arithmetic units, resulting in greater dependability. (Author)