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Question
Figure shows a block diagram of a detector for amplitude modulated signal. Identify the boxes ‘X’ and ‘Y’ and write their functions.
Solution
In this case the box X is a Rectifier while the box Y is an Envelope Detector.
The functions of the two boxes are —
Rectifier — It is used to convert the pure AC waveform to a pulsating DC waveform. This is needed to produce a constant voltage supply.
Envelope Detector — It is used to detect the modulating signal by separating it from the input AM wave.
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