Rural interface device

Abstract From the Canadian patent

Individual line service features on a multi-party two-wire telephone network are provided by apparatus that interfaces individual subscriber stations with the network. The apparatus includes a current sensor for detecting on hook and off hook modes of its station and a voltage sensor for determining the availability of the network to establish a bidirectional communication path with the station. Control logic circuitry responsive to the sensors sets the apparatus to an active state when the station is off hook and the network is available and to a nonactive state when the network is not available. Signal generators that are operably responsive to the control logic produce tone signals that …