Amplitude Modulation MCQ

41. Which of the following desirable features are possessed by SSB in comparison to AM?

  1. Less power is required
  2. Bandwidth required is less
  3. Antenna size can be reduced
  4. Lower frequency can be used

Select the correct answer using the codes given below

  1. iii and iv
  2. ii, iii and iv
  3. i and ii
  4. i, ii and iv
Answer
Answer. c

42. In AM, the percentage of total power in sideband is

  1. 10%
  2. 16.67%
  3. 23.34%
  4. 37.5%
Answer
Answer. d

43. A modulator is a device to

  1. Separate two frequencies
  2. Impress the information on to a radio frequency carrier
  3. Extract information from the carrier
  4. Amplify the audio frequency signal
Answer
Answer. b

44. If a large amount of information is to be transmitted in a small amount of time, we require

  1. Low-frequency signals
  2. Narrow-band signals
  3. Wide-band signals
  4. High-frequency signals
Answer
Answer. d

45. For an AM signal, the bandwidth is 10 kHz and the highest frequency component present is 705 kHz. The carrier frequency used for this AM signal is

  1. 700 kHz
  2. 695 kHz
  3. 710 kHz
  4. 705 kHz
Answer
Answer. a

46. If the modulation index of an AM wave is changed from 0 to 1, the transmitted power

  1. increases by 50%
  2. increases by 75%
  3. increases by 100%
  4. remains unaffected
Answer
Answer. a

47. An AM superheterodyne receiver with IF of 455 kHz is tuned to the carrier frequency of 1000 kHz. The image frequency is

  1. 545 kHz
  2. 1 MHz
  3. 1910 kHz
  4. 1455 kHz
Answer
Answer. c

48. In an AM signal when the modulation index is one, the maximum power Pt (where Pc is the carrier power) is equal to

  1. 1.5 Pc
  2. Pc
  3. 2 Pc
  4. 2.5 Pc
Answer
Answer. a