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Draw and explain PLL as an FM demodulator.

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Explanation:- FM signal which is to be demodulated is applied to input of PLL.VCO output must be identical to input signal if PLL is to remain locked. As PLL is locked, VCO starts tracking the instantaneous frequency in the FM input signal The error voltage produced at the output of the amplifier is proportional to the deviation of the input frequency from the centre frequency FM. Thus AC component of the error voltage represents the modulating signal. Thus at the error amplifier output we get demodulated FM output.

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