ALARM SYSTEM AUDIO INTERFACE TAMPER AND STATE DETECTION

摘要

An alarm system comprises: an audio interface comprising: a microphone; a state sensor for sensing a state at the audio interface; a signal generator for generating an inaudible state signal indicative of the state; a multiplexer for combining an audio signal from the microphone and the state signal; a control panel for monitoring sensed conditions at the audio interface; a conductor interconnecting the audio interface to the control panel carrying audio signal and the state signal as combined from the audio interface to the control panel.