| 摘要 |
PROBLEM TO BE SOLVED: To continuously perform speech communication, even when power failure occurs during a speech with a cordless telephone. SOLUTION: A cordless master unit part 1 is driven by using power from conductive time power source 5 at the time of conducting electricity. At the time of power failure, it is driven when a power source switching relay 7 switches to a power source 6 for power failure which utilizes power from a telephone line 3. A transmitting level of a RF unit 11 is lowered at the time of power failure, order to stably operate only with line power and thus, cordless speech communication becomes available. |
