| 摘要 |
PURPOSE:To attain the automatic control of transmission output over a wide band with high accuracy, by detecting the change in the output, correcting the fluctuation, and controlling the transmission output with a control signal corresponding to a channel frequency. CONSTITUTION:Transistors (TR)Q1, Q2 are operated as constant current sources, the base potential of the TRQ2 is kept constant with a constant voltage diode D3, and the collector current is adjusted by varying a resistor R4. Further, the collector current of the TRQ3is impressed to the base via a resistor R6 and is kept by a shift voltage Vs. Since a constant current Is being the sum of the collector currents of the TRs Q2, Q3 is constant, when a current I2 increases with the increase in a current Ip, an IB1 is decreased with the relation of Is=IB1+I2, then the internal resistance of the TRQ1 is increased, a control voltage VAPC is decreased, and the transmission output is kept constant by impressing the decrement of the driver stage being the prestage of the power amplifying stage. |
