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A message signal m(t)=4cos2000pit modula...

A message signal `m(t)=4cos2000pit` modulates the carrier `C(t)=cos2pif_(c)t` where `f_(c)=1MHz` to produce an `AM` signal. For demodulation using envelope detector the time constant `RC` should satisfy

A

`0.5ms lt RC lt 1ms`

B

`1mus lt lt RC lt lt 1ms`

C

`RC gt gt 1mus`

D

`RC gt gt 1mus`

Text Solution

Verified by Experts

The correct Answer is:
B
`f_(c)=1 MHz` and `f_(m)=2000Hz`
`(1)/(f_(c)) lt lt RC lt lt (1)/(f_(m))`
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NARAYNA-COMMUNICATION SYSTEM-Level-II(C.W)
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