Abstract: A test terminal includes a circuit for opening a loop switch to prevent setting up of calls from the terminal via a telephone line when a signal received from the telephone line via a first high-impedance connection exceeds a predetermined threshold indicating that the telephone line is busy. An alarm circuit indicates that any call from the terminal is prohibited. Operation of the terminal in discreet monitoring mode is also prohibited if the line is busy.
Abstract: A hand held telephone test set includes an internal strain relief interface configuration. The interface includes a well structure formed in a housing of the test set, with a plug receptacle disposed in the well structure. Additionally, a plug line channel is disposed in the housing and receives a plug line associated with a plug connected to the plug receptacle. The channel has a shape that provides strain relief for the plug/receptacle connection and the connecting line/plug connection.