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प्रश्न
A male voice after modulation-transmission sounds like that of a female to the receiver. The problem is due to ______.
विकल्प
poor selection of modulation index (selected 0 < m < 1).
poor bandwidth selection of amplifiers.
poor selection of carrier frequency.
loss of energy in transmission.
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उत्तर
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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