What is AGC (Automatic Gain Control)?

Automatic gain control is a closed-loop feedback management circuit in an amplifier. The reason for AGC is to keep an appropriate signal amplitude at it’s output, despite variation of the signal amplitude at the input. The average output signal level is utilized to progressively adjust the gain of the amplifiers, empowering the circuit to work with a greater range of input signal levels. It is utilized in most radio receivers to adjust the normal volume of various radio broadcasts because of differences in received signal strength, just as variations in a single station’s radio signal because of fading.