Method and apparatus for preventing pay telephone fraud and reducing handset vandalism

A method and apparatus for the detection and prevention of pin fraud in a coin operated telephone (2) is disclosed. A circuit (55) detects loss of loop current and triggers the opening of a pair of switches (S1,S2) thereby disconnecting the microphone from the phone. The A-relay is also switched to its refund and collect position. As a result, the fraud path through the microphone is disconnected, and the central office (4) can perform all its control functions unimpaired. Thus, the incentives for perpetrating the fraud are eliminated.