A carrier wave of peak voltage 12V is used to transmit a message signal. The peak voltage of the modulating signal in order to have a modulation index of 75 % is

Question

A carrier wave of peak voltage 12V is used to transmit a message signal. The peak voltage of the modulating signal in order to have a modulation index of 75 % is (A) 8V (B) 6V (C) 7V (D) 9 V

Tardigrade Admin · Accepted Answer

Here Ac=12V , Am=? modulation index μ c=75 %=0.75 Since μ c=(Am/Ac)⇒ 0.75=(Am/12) Am=0.75× 12=9V

Q. A carrier wave of peak voltage $12 V$ is used to transmit a message signal. The peak voltage of the modulating signal in order to have a modulation index of $75%$ is

$8 V$

$6 V$

$7 V$

$9 V$

Here $A_{c} = 12 V$ , $A_{m} = ?$
modulation index $μ_{c} = 75% = 0.75$
Since $μ_{c} = \frac{A _{m}}{A _{c}} \Rightarrow 0.75 = \frac{A _{m}}{12}$
$A_{m} = 0.75 \times 12 = 9 V$

Q. A carrier wave of peak voltage 12V is used to transmit a message signal. The peak voltage of the modulating signal in order to have a modulation index of 75% is

8V

6V

7V

9V