Abstract: Apparatus and methods are disclosed for anchoring each end of an armored telephone cord and restraint cable assembly to both the telephone housing and the associated handset. With respect to the handset, a removable anchor is positioned intermediate the receiver and transmitter ends along the hand-grip portion, the inside walls of the hand-grip being provided with a ledge or other means for transmitting longitudinal pulling forces along the restraint cable as a shear force along the peripheral sidewalls of the hand-grip portion.The housing anchor is specifically adapted for elbow type public telephones, and utilizes an elbow with the extremity of the armored telephone cord and restraint cable assembly and the cable stop fitted into the elbow generally parallel with the sidewall of the housing.

Abstract: A dynamic microphone and dynamic microphone amplifier used with a pay station telephone system has the amplifier physically located within a pay station and includes an isolation transformer to prevent ground faults in the dynamic microphone in the handset from being sensed by telephone network control circuitry. The dynamic microphone amplifier is mounted on a printed circuit board which includes an isolation transformer for the speaker element in the receiver of the handset. The leads from the transmitter dynamic microphone and receiver speaker are connected to the amplifier circuit board by way of a modular pin connector physically located in the pay station housing. The isolation transformers function as ground fault isolation devices to prevent ground faults in the handset from affecting the operation of the associated telephone system and to reduce the risk of electrric shock to a user.