| 摘要 |
PURPOSE:To prevent a state where an outside line is kept held by detecting a specific operation to an extension telephone set during communication and disconnecting a radio channel with a cordless telephone set during the communication and a line with a communicating party. CONSTITUTION:A main control part 15 detects the electric field intensity of radio waves from the radio extension control part 12 of a main unit 1 during the communication and disconnects the radio channel when the electric field intensity becomes lower than a prescribed value. Then, the main control part 15 detects the electric field intensity of the radio waves from the cordless telephone set 3 during the communication with the outside line by the cordless telephone set 3 and when the electric field intensity becomes lower than the prescribed value, disconnects the radio channel by controlling a radio channel control part 12, disconnects the outside line by controlling an outside line control part 11 and returns to a stand-by state. Also, when the specific operation to the extension telephone set 4 is detected while the cordless telephone set 3 performs the communication with the outside line, the main control part 15 disconnects the outside line during the communication and the radio channel with the cordless telephone set 3. |
