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प्रश्न
Define the term modulation. Draw a block diagram of a simple modulator for obtaining AM signal ?
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उत्तर
Modulation is the process in which low frequency message signal is superimposed on high frequency carrier wave so that they can be transmitted over long distances.
The block diagram for a simple modulator for obtaining AM signal is shown below:
संबंधित प्रश्न
The process of superimposing a low frequency signal on a high frequency wave is_______ .
The carrier wave is given by
C(t) = 2sin(8πt) volt.
The modulating signal is a square wave as shown. Find modulation index.
Why is Modulation index kept low?
In a communication system, what is meant by modulation?
In the block diagram of a simple modulator for obtaining an AM signal, shown in the figure, identify the boxes A and B. Write their function.
Answer the following question.
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A TV transmission tower antenna is at a height of 20 m. How much service area can it cover if the receiving antenna is (i) at ground level, (ii) at a height of 25 m? Calculate the percentage increase in area covered in case (ii) relative to case (i).
