Download Aptitude Crack
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Communication Systems - Engineering

Q1:

In amplitude modulation the rms value of radio frequency voltage after 40% modulation is 60 mV. If modulation is 80% the rms value after modulation will be about

A 50 mV

B 60 mV

C 66 mV

D 80 mV

ANS:C - 66 mV

Total Transmitted Voltage = Vc √{1+m^2/2}.
60E-3 = Vc √{1+.4^2/2}.
Vc = 0.0577 V.

New Total Transmitted Voltage = 0.0577 √{1+0.8^2/2}.
= 66mV.