Abstract: An audio-visual line test termination device for providing a characteristic signature to the telephone central office and a visual and an audible signal to the customer when a continuity test is made on a subscriber line having a pair of electrically conductive paths includes a miniature audio indicator, a light source and a minimum of associated electrical components to indicate to the central office test operator and the customer that the telephone subscriber line is in operating order. The instant invention may be utilized together with a housing that may be permanently installed across the subscriber line.

Abstract: A line test termination device for use on a telephone subscriber line having a pair of electrically conductive paths to provide an audio-visual indication when interrogated by the telephone central office and a subscriber test to indicate the operability of the subscriber line includes in combination, a first current path having a neon tube and an audio indicator connected in series; a second current path with a first normally open switch, a first resistor, a first zener diode and an indicating meter connected in series, all of which are placed in parallel with the first current path. Additionally included is a current polarizing circuit arrangement connected across the pair of electrically conductive paths to provide a unidirectional flow of current through the first and second current paths regardless of the polarity of voltage applied across the pair of electrically conductive paths.

Abstract: An audible test termination device for providing a characteristic signature to the telephone central office and an audible signal to the customer when a continuity test is made on a subscriber line having a pair of electrically conductive paths includes a miniature audio indicator and a minimum of associated electrical components to indicate to the central office test operator and the customer that the telephone subscriber line is in operating order. One embodiment of the instant invention may be utilized as an additional high impedance ringer for the customer. The present device may be permanently installed across the subscriber line.

Abstract: A varying impedance line test termination device for providing a characteristic signature to the telephone central office when a continuity test is made on a subscriber line having a pair of electrically conductive paths includes a first current path having a first resistor and a capacitor connected in series across the electrically conductive line paths and a second current path having a diode and a voltage breakover device connected in series across the capacitor. If the voltage breakover device is capable of emitting light, a flashing indication will be provided when the subscriber line is being interrogated.