HUMAN RESOURCE ISSUES AND COMMUNITY POLICING

A communication line monitor for use in a security or fire detection system of the type including a central alarm station and a communication line. A remote transmitter is coupled to the communication line at the remote end thereof and is assigned one unalterable preassigned address out of 6,561 different addresses. The remote transmitter continuously transmits an eight bit trinary code over the communication line corresponding to its preassigned address. A monitor located at the central alarm station is coupled to the communication line and indicates an alarm condition when the signals received from the remote transmitter fail to correspond to the remote transmitter's preassigned address. The monitor includes a plurality of switches to condition the monitor for identifying the remote transmitter's address. The switches are resettable to any other one of the different addresses. The remote transmitter also transmits a ninth bit which is used to verify a state of the communication line established by the central alarm station.