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A carrier wave of peak voltage 14 V is used for transmitting a message signal. The peak voltage of modulating signal given to achieve a modulation index of 80 % will be -

1. 11.2 V
2. 7 V
3. 22.4 V
4. 28 V

Correct answer: 11.2 V

Solution

Modulation index mu = Vm/Vc -> 0.80 = Vm/14 -> Vm = 11.2 V.

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