Abstract: A circuit board defining a flange is used to interconnect conductors located on the flange with corresponding conductors of a conventional connector. The flange includes a key slot and two flange slots which promote alignment between the circuit board and the connector. The flange slots define a mouth with an angled edge which urge the connector into alignment with the flange slots.

Abstract: A fail safe voice system and method for digital telephone networks. The system provides for operation of voice telephone equipment at a customer location when a fault occurs at the customer location. The system has a central office with an analog line termination/digital transceiver connected to subscriber loop lines. The customer location has a digital transceiver/analog station set interface connected to the subscriber loop lines and to the voice telephone equipment. In response to a fault at the customer location the voice telephone equipment is connected directly to the subscriber loop lines thereby eliminating the digital transceiver/analog station set interface.

Abstract: A circuit which prepares a conductive path between a ringing voltage generator and a telephone subscriber loop circuit prior to the application of ringing voltage to the conductive path. Photo coupled switching and monitoring circuits are used to coordinate application of ringing voltage with operation of a ring relay which completes the circuit path between the ringing voltage generator and the loop circuit.