PURPOSE: To realize a system which can transmit/receive the data of images or the like together with voices in the conference telephone system connecting plural conference telephone devices in the shape of a chain.
CONSTITUTION: Two channel dividing circuits are provided at least to divide a communication channel into the respective sub channels of control, voices and plural data in the case of connecting a conference telephone device being connected through one of more than two communication channels to the other conference telephone device and through the other channel to the different conference telephone device, a data channel switching circuit is provided to select whether data transmitted from the own device or data received from the other communication channel are outputted to a communication line and therefore, the data (image data) from the plural conference telephone devices can be simultaneously received.
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NISHINO YUTAKA
IKEDA YASUHISA
