Model 45A Two-Wire to Four-Wire Interface: Designed to interface a 2-wire full-duplex party-line( PL) intercom circuit with a 4-wire audio circuit associated with a matrix intercom system. Other specialized audio system interfacing applications can also be supported. Applications include television sports and special event broadcasting, theme park and theater installations, corporate events, and industrial testing environments.

Provides one full-featured Two-channel interface with automatic nulling. Includes front and back panel PL intercom connectors. Powered by PL intercom circuit or external source of 24 Vdc. Self contained portable unit. Unit can be rack mounted using an optional one or two unit rackmount front panel, (purchased separately)