Network interface device with disconnectable half-ringer

摘要

A telephone network interface device (NID) includes a test circuit that is readily connected and disconnected. The NID has a portion of an electrical circuit that connects a pair of provider wires as well as a pair of test wires to a pair of subscriber terminals. The test wires lead to a test circuit on the provider side of the housing of the NID. The subscriber terminals are located on the subscriber side of the housing to interconnect the provider wires with a pair of subscriber wires. A jack in the NID has a normal mode of operation in which the provider wires are electrically connected to the subscriber wires and a test mode of operation in which the provider wires are disconnected from the subscriber wires. A pair of lead wires are electrically connected to the jack and have free ends that connect to the subscriber terminals. This connects the test circuit in parallel physically and electrically between the provider wires and the subscriber wires. The free ends are readily disconnected from the subscriber terminals to disconnect the test circuit.