Patent ID: 7299015

Claim:
A transmitting output control circuit comprising: a power amplifying apparatus including: a power amplifier; a coupling capacitor for taking a part of a transmitting output signal of the power amplifier; and a first diode for inputting a signal corresponding to an output signal amplified by the power amplifier and generating a detecting signal; a directional coupler having a main line and sub line; a first terminating resistor coupled with one end of the sub line of the directional coupler; a switch disposed in the power amplifying apparatus; a second terminating resistor coupled with the switch; and a smoothing circuit coupled with a cathode of the first diode, wherein one end of the coupling capacitor and one end of the main line of the directional coupler are coupled with an output terminal of the power amplifier, wherein the switch is further coupled with an other end of the coupling capacitor, an other end of the sub line of the directional coupler, and an anode of the first diode, and the switch has a first state in which said other end of the coupling capacitor is coupled with the anode of the first diode and said other end of the sub line of the directional coupler is coupled with the second terminating resistor, and a second state in which said other end of the coupling capacitor is coupled with the second terminating resistor and said other end of the sub line of the directional coupler is coupled with the anode of the first diode, wherein the part of the transmitting output signal of the power amplifier is taken through one of the coupling capacitor and the directional coupler by switching the first state and the second state of the switch.