Apparatus for sensing and locating vibrations

摘要

A protective system employing vibration sensors for indicating the location of a vibration or of tampering with the system. There is employed a vibration sensor comprising first apparatus operative when the sensor is oriented in a first range of orientations for providing a momentary first impedance condition in response to vibration of at least a predetermined strength and second apparatus operative when the sensor is oriented in a second range of orientations for providing a steady state second impedance condition.