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Publication of JPS4986036ApublicationCriticalpatent/JPS4986036A/ja
G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
G08B13/00—Burglar, theft or intruder alarms
G08B13/16—Actuation by interference with mechanical vibrations in air or other fluid
G08B13/1654—Actuation by interference with mechanical vibrations in air or other fluid using passive vibration detection systems
G08B13/1681—Actuation by interference with mechanical vibrations in air or other fluid using passive vibration detection systems using infrasonic detecting means, e.g. a microphone operating below the audible frequency range
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Physics & Mathematics
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General Physics & Mathematics
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Measurement Of Mechanical Vibrations Or Ultrasonic Waves
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