Casio Computer Co., Ltd.

Tandy Corporation

Koji Yamana

Hideaki Ishida

Tomohisa Ishikawa

Takehiko Kayahara

Ryuichi Nakajima

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.

Telephone system with multiple extension telephones

Bar code data are read out by a bar code reader from a medium on which predetermined tone data are printed in the form of bar codes and are successively stored in a RAM. When a mode selection switch is set to a position 'NAVI', a LED provided in the vicinity of a performance key corresponding to the pitch of a tone next to be produced next, is turned on under the control of a control section. Performance of music can be obtained by successively operating performance keys indicated by associated LEDs turned on one after another.

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Tokyo, Japan

Koji Yamana