SEISMOACOUSTIC DETECTOR Russian patent published in 1995 - IPC

FIELD: alarm signalling. SUBSTANCE: seismoacoustic detector includes acoustic microphone 1 and geophone 2 connected to proper amplifiers 3 and 4, transmitter 14 with aerial and power supply source 13, logic processing unit 5, matching unit 11 linked with two-wire communication line to control desk 12 to which input power supply source 13 is connected and to which output transmitter 14 is coupled. Logic processing unit 5 is manufactured in the form of two threshold units 6 and 7, selector 8 of step pulses, former 9 of analysis time and pulse counter 10. Detector can be used in two versions: with transmission of information over radio channel and wire channel and over wire channel only. In both versions of detector power supply to key energy-consuming units is fed only with emergence of ALARM signal which reduces power consumption by more than an order. EFFECT: increased noise immunity and secretiveness, reduced power consumption and expanded application field. 2 cl, 2 dwg