All in good condition
The AD903 2 to 4 wire adapter allows connection of almost any audio source to a Tecpro ring intercom 2 wire system. For example, most broadcast video cameras have in-built 4 wire comms systems which are cabled within the main video cable. Use of an AD903 at the camera control unit will allow that camera to appear as a part of the Tecpro communication system, while minimising extra wiring and expense. The AD903 will work with most separate send and receive communications systems in the same way. Levels are totally independently adjustable on input or output.