Question 1: Palette 1/15

AP-EAPCET 2025 MCQ

The heights of tansmitting and receiving antennas are respectively $\frac{1}{20000}$ and $\frac{1}{80000}$ times the radius of the

Earth. The maximum distance between these two antennas for satisfactory communication in line of sight mode is

(Radius of the Earth $=6.4 \times 10^6 \mathrm{~m}$ )

A

48 km

B

96 km

C

320 km

D

192 km

Question 2: Palette 2/15

AP-EAPCET 2025 MCQ

In amplitude modulation, if a message signal of 5 kHz 2 is modulated by a carrier wave of frequency 900 kHz , then the frequencies of the side bands are

A

$905 \mathrm{kHz}, 895 \mathrm{kHz}$

B

$900 \mathrm{kHz}, 800 \mathrm{kHz}$

C

$800 \mathrm{kHz}, 700 \mathrm{kHz}$

D

$1000 \mathrm{kHz}, 900 \mathrm{kHz}$

Question 3: Palette 3/15

AP-EAPCET 2025 MCQ

If the ratio of the maximum and minimum amplitudes of an amplitude modulated wave is $7: 3$, then the modulation index is

A

0.6

B

0.7

C

0.4

D

0.3

Question 4: Palette 4/15

AP-EAPCET 2025 MCQ

Ionosphere acts as a reflector for the frequency range of

A

$3-30 \mathrm{kHz}$

B

$3-30 \mathrm{MHz}$

C

$3-30 \mathrm{~Hz}$

D

$3-30 \mathrm{GHz}$

Question 5: Palette 5/15

AP-EAPCET 2025 MCQ

If the maximum and minimum amplitudes of a modulated wave are 25 V and 5 V respectively, then the modulation index is

A

$\frac{1}{5}$

B

$\frac{1}{3}$

C

$\frac{3}{2}$

D

$\frac{2}{3}$

Question 6: Palette 6/15

AP-EAPCET 2025 MCQ

For transmitting a signal of frequency 1000 kHz , the minimum length of the antenna is

A

30 m

B

50 m

C

75 m

D

1500 m

Question 7: Palette 7/15

AP-EAPCET 2025 MCQ

If in an amplitude modulated wave, the maximum amplitude is 14 V and the modulation index is 0.4 , then the amplitude of the carrier wave is

A

4 V

B

8 V

C

12 V

D

10 V

Question 8: Palette 8/15

AP-EAPCET 2025 MCQ

In amplitude modulation of waves, the maximum amplitude is 30 mV and minimum amplitude is 5 mV , then the modulation index is

A

$\frac{4}{7}$

B

$\frac{3}{7}$

C

$\frac{5}{7}$

D

$\frac{2}{7}$

Question 9: Palette 9/15

AP-EAPCET 2025 MCQ

If the sum of heights of transmitting and receiving antennas in line of sight of communication is ' $h$ ' then the height of receiving antenna, to have the range maximum is

A

$\frac{h}{2}$

B

$\frac{h}{4}$

C

2 h

D

$\frac{2 h}{3}$

Question 10: Palette 10/15

AP-EAPCET 2024 MCQ

Which one of the following is not classified as pulse modulation?

A

Pulse duration modulation

B

Pulse amplitude modulation

C

Pulse band modulation

D

Pulse position modulation

Question 11: Palette 11/15

AP-EAPCET 2024 MCQ

The maximum distance between the transmitting and receiving antennas for satisfactory communication in line of sight mode is 57.6 km . If the height of the receiving antenna is 80 m , the height of the transmitting antenna is (radius of earth $=6.4 \times 10^6 \mathrm{~m}$ )

A

28.8 m

B

51.2 m

C

25.6 m

D

14.4 m

Question 12: Palette 12/15

AP-EAPCET 2024 MCQ

An information signal of frequency 10 kHz is modulated with a carried wave of frequency $3.62 \mathrm{MHz}^{}$ The upper side and lower side frequencies are

A

3650 kHz and 3590 kHz

B

3620 kHz and 3600 kHz

C

3610 kHz and 3580 kHz

D

3600 kHz and 3620 kHz

Question 13: Palette 13/15

AP-EAPCET 2024 MCQ

In amplitude modulation, the amplitude of the carrier wave is 10 V and the amplitude of one of the side bands is 2 V . Then, the modulation index is

A

0.4

B

0,6

C

0.7

D

0.5

Question 14: Palette 14/15

AP-EAPCET 2024 MCQ

A carrier is simultaneously modulated by two sine waves with modulation indices of 0.3 and 0.4 , then the total modulation index is

A

1

B

0.12

C

0.5

D

0.7

Question 15: Palette 15/15

AP-EAPCET 2024 MCQ

If the maximum and minimum voltages of an $A M$ wave are $V_{\max }$ and $V_{\min }$ respectively. Then, the modulation factor $m$ is

A

$\left(V_{\text {max }}+V_{\text {min }}\right) /\left(V_{\text {max }} \cdot V_{\text {min }}\right)$

B

$\left(V_{\text {max }}-V_{\text {mi }}\right) /\left(V_{\text {max }}+V_{\text {min }}\right)$

C

$2 V_{\text {max }}-V_{\text {min }} /\left(V_{\text {max }}+V_{\text {max }}\right)$

D

$\left(V_{\text {nes }}+V_{\text {min }}\right) /\left(V_{\text {max }}-V_{\text {man }}\right)$