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Karnataka Board PUCPUC Science 2nd PUC Class 12

A male voice after modulation-transmission sounds like that of a female to the receiver. The problem is due to ______.

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Question

A male voice after modulation-transmission sounds like that of a female to the receiver. The problem is due to ______.

Options

  • poor selection of modulation index (selected 0 < m < 1).

  • poor bandwidth selection of amplifiers.

  • poor selection of carrier frequency.

  • loss of energy in transmission.

MCQ
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Solution

A male voice after modulation-transmission sounds like that of a female to the receiver. The problem is due to poor bandwidth selection of amplifiers.

Explanation:

In this problem, the frequency of the modulated signal received becomes more, due to improper selection of bandwidth.

This happens because bandwidth in amplitude modulation is equal to twice the frequency of modulating signal.

But, the frequency of male voice is less than that of a female.

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Chapter 15: Communication Systems - Exercise [Page 100]

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NCERT Exemplar Physics Exemplar [English] Class 12
Chapter 15 Communication Systems
Exercise | Q 15.07 | Page 100

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