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 shorting cage is provided in a telephone terminal housing having a protector well so that when the protector device is removed from its cooperating well the shorting mechanism in the form of a cage will cause the line to remain shorted until a replacement protector is reinserted into the terminal well.

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.

Abstract: A telephone ringer isolator includes an electronic switch which enables it to operate at reduced ringer voltages. In the ringer isolator, the central office ringing signal is rectified and voltage doubled across a circuit containing two diodes and two capacitors. The second capacitor is connected across a neon tube. When the voltage across the second capacitor rises to a preselected value, the neon tube is fired to emit light onto a light sensitive resistor which feeds gate current to a Triac to turn the Triac on. The Triac, in turn, grounds the telephone ringer.

Abstract: A station identification circuit arrangement for use with central office equipment that utilizes automatic detection equipment for the detection of one of four parties on a four party-line where a call is initiated from a preselected party's telephone without requiring access to or rewiring of the party's telephone.

Abstract: A screw-in station protector assembly includes a carrier housing containing a shorting cage which is biased by a compression to urge the cage and gas tube arrester assembly outwardly. The gas tube assembly contained within the cage includes a two electrode gas tube and a sealed external back-up air gap protector. The screw-in assembly is particularly adapted for retro-fitting/replacement of carbon block arresters without modification.

Abstract: A screw-in station protector assembly includes a carrier housing containing a shorting cage which is biased by a compression to urge the cage and gas tube arrester assembly outwardly. The gas tube assembly contained within the cage includes a two electrode gas tube. The gas tube is within a jacket which forms a sealed external back-up air gap protector. The screw-in-assembly is particularly adapted for retro-fitting/replacement of carbon block arresters without modification.

Abstract: Laminar air gap devices include two overlapping conductive layers separated by a non-metallic insulating layer. The insulating layer is perforated to provide at least one air gap between the conductive layers. The devices are positioned between a line electrode and ground electrode of a gas filled surge arrester and resiliently retained thereon by conductive clips. Non-metallic fusible elements, preferably plastic, are interposed between the clip legs and the associated electrode. The fusible element may also be the insulating layer between the conductive layers.

Abstract: A highly reliable gas tube arrester capable of protecting both the input and output lines from an excess voltage appearing thereon, includes a hermetically sealed housing, having a plurality of electrodes affixed therein and spaced in a predetermined manner between themselves and the housing to provide a plurality of spark gaps. A breakdown of any one of the spark gaps will ionize a gas disposed within the housing providing a low impedance path between all of the electrodes to the housing which is normally connected to ground potential.

Abstract: A unit adapted to be connected to the tip party's subscriber's drop in a two-party line without requiring access to or rewiring of the tip party's telephone and having interconnected ringer isolator and ANI mark circuits. The ringer isolator and the ANI mark circuits may also be used individually.

Abstract: A repeater bypass protection apparatus includes a means of providing a low current path between the input and output transmission lines coupled to a repeater amplifier. Under normal operating conditions the low current path presents a relatively high impedance and does not interfere with the operation of the repeater amplifier. Under high voltage transient conditions the protection apparatus is activated and effectively protects the repeater amplifier from being destroyed.