Modulation And Demodulation(Electrical Engineering ) Questions and Answers

Question 1. In a superhetrodyne receiver, the difference frequency is chosen as the IF rather than the sum frequency because ___________
  1.    The difference frequency is closer to oscillator frequency
  2.    Lower frequencies are easier to amplify
  3.    Only the difference frequency can be modulated
  4.    None of the above
Explanation:-
Answer: Option B. -> Lower frequencies are easier to amplify
Question 2. Demodulation is done in ___________
  1.    Receiving antenna
  2.    Transmitter
  3.    Radio receiver
  4.    Transmitting antenna
Explanation:-
Answer: Option C. -> Radio receiver
Question 3. Modulation is done in ___________
  1.    Transmitter
  2.    Radio receiver
  3.    Between transmitter and radio receiver
  4.    None of the above
Explanation:-
Answer: Option A. -> Transmitter
Question 4. Superhertodyne principle refers to
  1.    Using a large number of amplifier stages
  2.    Using a push-pull circuit
  3.    Obtaining lower fixed intermediate frequency
  4.    None of the above
Explanation:-
Answer: Option C. -> Obtaining lower fixed intermediate frequency
Question 5. In the above question, what is the power in sidebands?
  1.    8 kW
  2.    6 kW
  3.    06 kW
  4.    9 kW
Explanation:-
Answer: Option C. -> 06 kW
Question 6. Overmodulation (amplitude) occurs when signal amplitude is ___________ carrier amplitude
  1.    Equal to
  2.    Greater than
  3.    Less than
  4.    None of the above
Explanation:-
Answer: Option B. -> Greater than
Question 7. If level of modulation is increased ___________ power is increased
  1.    Carrier
  2.    Sideband
  3.    Carrier as well as sideband
  4.    None of the above
Explanation:-
Answer: Option B. -> Sideband
Question 8. If modulation is 100% then signal amplitude is ___________ carrier amplitude
  1.    Equal to
  2.    Greater than
  3.    Less than
  4.    None of the above
Explanation:-
Answer: Option A. -> Equal to
Question 9. At 100% modulation, the power in each sideband is ___________ of that of carrier
  1.    50%
  2.    40%
  3.    60%
  4.    25%
Explanation:-
Answer: Option D. -> 25%
Question 10. In a transmitter ___________ oscillator is used
  1.    Hartley
  2.    RC phase-shift
  3.    Wien-bridge
  4.    Crystal
Explanation:-
Answer: Option D. -> Crystal
© Lakshya_Education.com, All Right Reserved.
Contact Us services