Tandy Corporation

Ryuichi Nakajima

Koji Yamana

An improved telephone system in which a plurality of telephone units connected to a common telephone line is directly connected to an outside telephone line. Each telephone unit contains complete capability for making outside calls, for making extension calls, and for the automatic exchange control of the use of the common telephone line. This telephone system provides functions, including making multiple simultaneous calls on a single telephone line without requiring separate exchange equipment, additional extension or signal lines, or any sacrifice in signal quality. Furthermore, the telephone units in this system can be connected to more than one outside telephone line to expand the system capacity.

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Tokyo, Japan

Ryuichi Nakajima