| 摘要 |
PURPOSE:To prevent a transmission output reduction in an on-vehicle adaptor by providing an on-vehicle adaptor connection detection means to the radio equipment and varying a reference voltage so as to increase the transmission output when the radio equipment is connected to the on-vehicle adaptor. CONSTITUTION:When the radio equipment is connected to an on-vehicle adaptor, a voltage is applied from the on-vehicle adaptor to a CPU 7 of the radio equipment and a discrimination section 9 in the inside of the CPU 7 detects the voltage. When no voltage is applied, it is discriminated to be no connection and a present transmission output is kept, and when the voltage is present, it is discriminated that connection is made, and the CPU 7 outputs an instruction to increase the power to a power control 6. The power control 6 controls a reference voltage of an APC circuit 5 to increase the transmission output and the increased output is outputted from the radio equipment via a directional coupler 2, an antenna switch 3 and a low pass filter 4. Since the increased output power is reduced by an insertion loss of a multicoupler 8 of the on- vehicle adaptor, the same output before the radio equipment is connected to the on-vehicle adaptor is obtained. |
