| 摘要 |
PURPOSE:To perform reception stable against variation in electric field level by using an AGC circuit and an attenuator as two systems, and operating the attenuator provided to an input circuit during large input. CONSTITUTION:In accordance with the output level of a detector 7, the 1st AGC circuit 12 operates. The 1st AGC circuit 12 controls the gains of a high frequency amplifying circuit 3 and an intermediate frequency amplifying circuit 6 to hold the output level of the detector 7 below a certain value. The 1st AGC circuit 12, however, has a limit of control, so an excessive input signal when arriving allows the intermediate frequency amplifying circuit 6 to output a signal which exceeds the certain value. Only when said case occurs, the 2nd AGC circuit 13 controls an attenuator 11 to hold the output signal below the certain value. Therefore, the operation of the receiver of a radio control system is stabilized. |
