Order wire accommodation system for interoffice communications

Abstract

An order wire accommodation system comprises four interface boxes each of which has the same order wire interface section as the others. The order wire interface section has a circuit which digitally adds order wire signals of the transmission lines from two ports and the order wire signals which interface with the other interface boxes or a telephone through the other two ports. Each output from the order wire interface section is a sum of all the order wire signals inputted except for those of the order wire interface section itself. Because of a provision of two ports which interface externally, the interface boxes can be cascaded connected to one another, by which order wire communications among all the transmission lines accommodated in the interface boxes become possible. Further, the order wire accommodation system can be minimized and be simplified.

Dependencies are inferred from the claim text.