| 摘要 |
PROBLEM TO BE SOLVED: To attain a speech through a wired line even when radio communication is not available by breaking only a power supply from a power supply means to a radio section when an output voltage reaches a preset voltage or below. SOLUTION: Power supply to a radio section 6 is conducted via a power supply breaking section 10 and power is directly supplied to a control section 1 or the like. A battery voltage detection section 11 detects an output voltage of a battery 9 and provides an output of the detection result to the control section 1 as a voltage signal Sv . When the output voltage of the battery 9 is decreased to be a setting voltage or below, the control section 1 outputs an interrupt signal Ss to the power supply breaking section 10. Thus, the power supply interrupt section 10 is driven to stop power supply of the radio section 6. That is, the cordless telephone set is not available for radio communication. Furthermore, a fact of not available radio communication is displayed on a ten-key/LCD section 3 and then the user recognizes it that radio communication and wired communication via a master set are not available. |
