State the need of AGC. List the different types of AGC with neat graph.

State the need of AGC. List the different types of AGC with neat graph.
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Answer :

Need of AGC:- The need or purpose of AGC circuit is to maintain the output voltage level (volume) of radio receiver constant over a wide range of RF input signal level.  AGC also helps to smooth out the rapid fading which may occur with long distance short wave reception & prevents overloading of the last IF amplifier which might otherwise have occurred 

Types of AGC:-

1) Simple AGC

2) Delayed AGC

Graphical representation of AGC:- 

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