| 摘要 |
PURPOSE:To provide a mobile telephone set capable of uninterrupted communication even when charged capacity is lowered and further even when the telephone set is away from the usable area of a radio base station. CONSTITUTION:A communication system 20 is constituted of a mobile telephone set 10, a mobile network 20A and a fixed network 20B. The mobile telephone set 10 is provided with a radio channel control circuit 17 for performing communication with a radio base station 21 of the mobile network, a cable control circuit 18 for performing communication with a terminal station 25 of the fixed network, and a channel switching circuit 16 for selecting any one of two control circuits. When the charging capacity of the telephone set 10 is lowered and radio communication is disabled, the communication due to the telephone set 10 is uninterruptedly enabled by cable communication only by inserting a plug 11a of a flat cable to a jack 25a on the side of the fixed network. Even at the place away from the usable area of the radio base station 21 or even at the place with weak radio wave such as in a valley of buildings, the clear communication of the telephone set 10 is enabled by selecting the cable communication. |
