Modulation

1. A 100 V carrier is made to vary between 160 V and 40 V by the signal. What is the modulation factor?

  1. 3
  2. 6
  3. 5
  4. None of the above

Correct answer: (B)
6

2. A 50 kW carrier is to be amplitude modulated to a level of 85%. What is the carrier power after modulation?

  1. 50 kW
  2. 5 kW
  3. 8 kW
  4. 25 kW

Correct answer: (A)
50 kW

3. A high Q tuned circuit will permit an amplifier to have high _________…

  1. Fidelity
  2. Frequency range
  3. Sensitivity
  4. Selectivity

Correct answer: (D)
Selectivity

4. As the modulation level is increased, the carrier power _________

  1. Is increased
  2. Remains the same
  3. Is decreased
  4. None of the above

Correct answer: (B)
Remains the same

5. At 100% modulation, the power in each sideband is _________ of that of carrier

  1. 50%
  2. 40%
  3. 60%
  4. 25%

Correct answer: (D)
25%

6. Demodulation is done in _________

  1. Receiving antenna
  2. Transmitter
  3. Radio receiver
  4. Transmitting antenna

Correct answer: (C)
Radio receiver

7. If a radio receiver amplifies all the signal frequencies equally well, it is said to have high _________

  1. Sensitivity
  2. Selectivity
  3. Distortion
  4. Fidelity

Correct answer: (D)
Fidelity

8. If Amin = 40 and Amax = 60, what is the percentage of modulation?

  1. 20 %
  2. 40 %
  3. 50 %
  4. 10 %

Correct answer: (A)
20 %

9. If level of modulation is increased _________ power is increased

  1. Carrier
  2. Sideband
  3. Carrier as well as sideband
  4. None of the above

Correct answer: (B)
Sideband

10. If modulation is 100% then signal amplitude is _________ carrier amplitude

  1. Equal to
  2. Greater than
  3. Less than
  4. None of the above

Correct answer: (A)
Equal to

Page 1 of 4