| 摘要 |
PROBLEM TO BE SOLVED: To obtain a cellular cordless master machine which is capable of supplying stable service to a slave machine from the time when a power source is turned on. SOLUTION: In the cellular cordless master machine providing a cellular cordless slave machine with a service with a cellular base station, a decision means 28 deciding the significance/non-significance of a received signal and a reference frequency control means 24 calibrating the oscillation frequency of a reference oscillator 25 based on the frequency of the received signal are provided. The reference frequency control means 24 catches the time when the decision means 28 decides the non-significance of the received signal and receives the transmission signal of the cellular base station till the temperature rise of the reference oscillator 25 is saturated, and the calibration of the oscillation frequency of the reference oscillator 25 is repeated. Till the reference oscillator 25 performs a temperature saturation just after a power source is turned on, the transmission signal of the cellular base station is repeated and received, the oscillation frequency of the reference oscillator 25 is calibrated and the deviation of the oscillation frequency accompanying the temperature rise is corrected without stopping the service for the slave machine. |
