Rangemeter for XM23 Laser Rangefinder Model II

摘要

A modified rangemeter, designated model II, was constructed and determined capable for use with the XM23 Laser Rangefinder. The model II design is a high-speed, miniature, digital time-interval counter that displays range readings from 200 to 19,995 meters when coupled to the rangefinder. This range capability is twice that of the model I rangemeter. Another advantage of the model II design is that it includes a target counter, thus allowing the operator to range on any one of five target echoes. Operation of the rangemeter is based on start and stop pulses that are received from the rangefinder. The counter then computes and displays the range to the nearest 5 + or - 5 m on a solid-state electroluminescent readout. The readout assembly is optically coupled between the computing circuits and a photoconductive readout matrix. The rangemeter system operates from -55 to +75 degrees C with a 5- to 7-v supply. The time base is a 29.971-Mc crystal oscillator; the computing circuits are high-frequency flip-flops. (Author)