If a message signal of frequency 10 kHz and p | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) The modulation index $M$ is given by the formula $M = \frac{V_m}{V_c}$, where $V_m$ is the peak voltage of the message signal and $V_c$ is the pea

Vedclass · Accepted Answer

decreased by $20 \%$

Vedclass · Answer

(C) The modulation index $M$ is given by the formula $M = \frac{V_m}{V_c}$, where $V_m$ is the peak voltage of the message signal and $V_c$ is the peak voltage of the carrier wave.Given $V_m = 12 V$ and initial modulation index $M_1 = 0.6$.For the first case: $0.6 = \frac{12}{V_c} \Rightarrow V_c = \frac{12}{0.6} = 20 V$.For the second case, we want the modulation index $M_2 = 0.75$ with the same message signal $V_m = 12 V$.$0.75 = \frac{12}{V_c'} \Rightarrow V_c' = \frac{12}{0.75} = 16 V$.The change in carrier peak voltage is $\Delta V = V_c - V_c' = 20 V - 16 V = 4 V$.The percentage change is $\frac{\Delta V}{V_c} 	imes 100 \% = \frac{4}{20} 	imes 100 \% = 20 \%$.Since the voltage decreased from $20 V$ to $16 V$, the carrier peak voltage should be decreased by $20 \%$.

If a message signal of frequency $10 kHz$ and peak voltage $12 V$ is used to modulate a carrier wave of frequency $1 MHz$, the modulation index is $0.6$. To make the modulation index $0.75$, the carrier peak voltage should be

Similar Questions

Long range radio transmission is possible when the radio waves are reflected from the ionosphere. For this to happen,the frequency of the radio waves must be in the range:

For $VHF$ signal broadcasting,what is the maximum service area in $km^{2}$ that will be covered by an antenna tower of height $30\, m$,if the receiving antenna is placed at the ground? Let the radius of the earth be $6400\, km$. (Round off to the nearest integer) (Take $\pi$ as $3.14$)

Which frequency range is suitable for sky wave propagation?

$A$ baseband signal of $3.5\, MHz$ frequency is modulated with a carrier signal of $3.5\, GHz$ frequency using amplitude modulation. What should be the minimum size of antenna required to transmit the modulated signal?

In an $AM$ wave,the total power is $900 \ W$. For $100\%$ modulation,the power transmitted in the sidebands is ... $W$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module