Modulation And Demodulation MCQ

Test your knowledge with important Modulation And Demodulation MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more Modulation And Demodulation MCQs at Bissoy

• The IF is 455 kHz. If the radio receiver is tuned to 855 kHz, the local oscillator frequency is ___________
  ক

  455 kHz

  খ

  1310 kHz

  গ

  1500 kHz

  ঘ

  1520 kHz
• In a TRF radio receiver, the RF and detection stages are tuned to ___________
  ক

  Radio frequency

  খ

  IF

  গ

  Audio frequency

  ঘ

  None of the above
• The letters AVC stand for ___________
  ক

  Audio voltage control

  খ

  Abrupt voltage control

  গ

  Automatic volume control

  ঘ

  Automatic voltage control
• Overmodulation results in ___________
  ক

  Weakening of the signal

  খ

  Excessive carrier power

  গ

  Distortion

  ঘ

  None of the above
• In superhetrodyne receiver, the input at mixer stage is ___________
  ক

  IF and RF

  খ

  RF and AF

  গ

  IF and AF

  ঘ

  RF and local oscillator signal
• In radio transmission, the medium of transmission is ___________
  ক

  Space

  খ

  An antenna

  গ

  Cable

  ঘ

  None of the above
• In a radio receiver, we generally use ___________ oscillator as a local oscillator
  ক

  Crystal

  খ

  Wien-bridge

  গ

  Phase-shift

  ঘ

  Hartley
• In an AM wave useful power is carrier by ___________
  ক

  Carrier

  খ

  Sidebands

  গ

  Both sidebands and carrier

  ঘ

  None of the above
• When the modulating signal controls the frequency of the carrier, we get___________
  ক

  Phase modulation

  খ

  Amplitude modulation

  গ

  Frequency modulation

  ঘ

  May be any one of the above
• In India, ___________ modulation is used for radio transmission
  ক

  Frequency

  খ

  Amplitude

  গ

  Phase

  ঘ

  None of the above
• The signal voltage induced in the aerial of a radio receiver is of the order of ___________
  ক

  mV

  খ

  µV

  গ

  V

  ঘ

  None of the above
• If Amin = 40 and Amax = 60, what is the percentage of modulation?
  ক

  20%

  খ

  40%

  গ

  50%

  ঘ

  10%
• The function of ferrite antenna is to ___________
  ক

  Reduce stray capacitance

  খ

  Stabilise d.c. bias

  গ

  Increase the Q of tuned circuit

  ঘ

  Reduce noise
• The diode detector in an AM radio receiver is usually found ___________
  ক

  Before the first RF stage

  খ

  After the first RF stage

  গ

  After several stages of amplification

  ঘ

  None of the above
• In a radio receiver, noise is generally developed at ___________
  ক

  IF stage

  খ

  Receiving antenna

  গ

  Audio stage

  ঘ

  RF stage
• Modulation refers to a low-frequency signal controlling the ___________
  ক

  Amplitude of the carrier

  খ

  Frequency of the carrier

  গ

  Phase of the carrier

  ঘ

  May be any of the above
• As the modulation level is increased, the carrier power ___________
  ক

  Is increased

  খ

  Remains the same

  গ

  Is decreased

  ঘ

  None of the above
• In an AM wave, the majority of the power is in ___________
  ক

  Lower sideband

  খ

  Upper sideband

  গ

  Carrier

  ঘ

  None of the above
• The major advantage of FM over AM is ___________
  ক

  Reception is less noisy

  খ

  Higher carrier frequency

  গ

  Smaller bandwidth

  ঘ

  Small frequency deviation
• A 50 kW carrier is to be amplitude modulated to a level of 85%. What is the carrier power after modulation?
  ক

  50 kW

  খ

  5 kW

  গ

  8 kW

  ঘ

  25 kW
• In amplitude modulation, the ___________ of carrier is varied according to the strength of the signal.
  ক

  Amplitude

  খ

  Frequency

  গ

  Phase

  ঘ

  None of the above
• A 100 V carrier is made to vary between 160 V and 40 V by the signal. What is the modulation factor?
  ক

  3

  খ

  6

  গ

  5

  ঘ

  None of the above
• In amplitude modulation, bandwidth is ___________ the audio signal frequency
  ক

  Thrice

  খ

  Four times

  গ

  Twice

  ঘ

  None of the above
• If a radio receiver amplifies all the signal frequencies equally well, it is said to have high ___________
  ক

  Sensitivity

  খ

  Selectivity

  গ

  Distortion

  ঘ

  Fidelity
• A high Q tuned circuit will permit an amplifier to have high ___________
  ক

  Fidelity

  খ

  Frequency range

  গ

  Sensitivity

  ঘ

  Selectivity
• The superhetrodyne principle provides selectivity at ___________ stage
  ক

  RF

  খ

  IF

  গ

  audio

  ঘ

  Before RF
• Most of the amplification in a superhetrodyne receiver occurs at ___________ stage
  ক

  IF

  খ

  RF amplifier

  গ

  Audio amplifier

  ঘ

  Detector
• In TV transmission, sound signal is ___________ modulated
  ক

  Amplitude

  খ

  Frequency

  গ

  Phase

  ঘ

  None of the above
• In TV transmission, picture signal is ___________ modulated
  ক

  Frequency

  খ

  Phase

  গ

  Amplitude

  ঘ

  None of the above
• Man made noise are ___________ variations.
  ক

  Amplitude

  খ

  Frequency

  গ

  Phase

  ঘ

  Both phase and frequency