| 摘要 |
PROBLEM TO BE SOLVED: To provide a radio telephony system simple in configuration and capable of being utilized for both a cordless telephone and a portable telephone set. SOLUTION: A receiver driving amplifier 24 at a cordless telephone base band part 2 drives a receiver 7 by adding the output of an expander 23 showing an audio signal from a master set and the output of a receiver driving amplifier 48 at a portable telephone based band part 4. In a cordless telephone mode, a power supply part 8 turns off the power source of the portable telephone base band part 4. The receiver driving amplifier 24 drives the receiver 7 based on the output of the expander 23 and reproduces a voice from the master set. In a portable telephone mode, on the other hand, the power supply part 8 supplies no power to a cordless telephone radio part 3 and the output of the expander 23 is stopped. The receiver driving amplifier 24 drives the receiver 7 based on the output of the receiver driving amplifier 48 and reproduces a voice from a public radio base station. |
