Alarm unit using IR detector - has thermal and optical energy detectors connected to electronic circuit with pulse former, audio amplifier and telephone (NO 1.12.80)

摘要

The infrared detector is connected to an electronic circuit which enables thermal energy to produce sound. The components of the electronic circuit are an OR gate, an audio frequency amplifier, an AND gate, a bistable unit, a counter, a pulse generator and a telephone. The pulse generator produces signals at intervals of about 200 milliseconds. Most of the electronic components are connected as output to the AND gate which responds to coincident signals from the infrared detector and an optical diode in the centre of a reflector mirror so that the receiver may be used for directional pick-up from a distant object. The amplified pulse output is fed to the OR gate with a signal from the infrared detector.