Oscillator MCQs

1. The following are the necessary requirements of an oscillator

  1. Amplitude stability
  2. Frequency stability
  3. Power stability
  4. Both A and B

Answer
Answer. d

2. The feedback factor of a Wien bridge oscillator using Op-Amp is

  1. 1/3
  2. 1/4
  3. 1/2
  4. 1

Answer
Answer. c

3. Which of the following oscillators are used for low frequency (LF) applications

  1. LC oscillators
  2. RC oscillators
  3. Both LC and RC Oscillators
  4. None of these

Answer
Answer. b

4. Feedback circuit in an oscillator can be accomplished by

  1. Resistive coupling between input and output
  2. Capacitive coupling between input and output
  3. Inductive coupling between input and output
  4. Any one or combinations of the above methods

Answer
Answer. d

5. For audio frequency applications, the popular oscillator used is

  1. Wien bridge oscillator
  2. Hartley oscillator
  3. Crystal oscillator
  4. Phase shift oscillator

Answer
Answer. a

6. Relaxation Voltage controlled oscillators are used to generate

  1. Sinusoidal wave
  2. Triangular wave
  3. Sawtooth wave
  4. Both B and C

Answer
Answer. d

7. The Barkhausen criterion for an oscillator

  1. Loop gain should be unity
  2. Loop gain should be less than unity
  3. The phase of a feedback signal with respect to input should be 0° or 360°
  4. Both A and C

Answer
Answer. d

8. One of the following is the primary function of an oscillator

  1. produces sinusoidal oscillations
  2. generates non sinusoidal waveforms
  3. generates sustained oscillations at a constant amplitude and specific frequency
  4. none of the above

Answer
Answer. c

9. Which of the following is not a sinusoidal oscillator?

  1. LC oscillator
  2. RC phase shift oscillator
  3. Relaxation oscillator
  4. Crystal oscillator

Answer
Answer. c

10. LC oscillators are used for produce a waveform with frequency ranging from

  1. 1MHz to 500 MHz
  2. 100 KHz to 500 MHz
  3. 1 KHz to 1 MHz
  4. 1MHz to 100 GHz

Answer
Answer. a

11. A quartz crystal oscillator consists of

  1. only series resonant frequency
  2. only parallel resonant frequency
  3. both series and parallel frequencies
  4. neither series nor parallel frequency

Answer
Answer. c

12. Colpitts oscillator is also called as

  1. Tank circuit oscillator
  2. LC oscillator
  3. Resonant circuit oscillator
  4. All of the above

Answer
Answer. d

13.  Which oscillators are easy to fabricate in a monolithic IC?

  1. Crystal oscillator
  2. Hartley oscillator
  3. Wien bridge oscillator
  4. Relaxation oscillator

Answer
Answer. d

14. Voltage controlled oscillators are used commonly in

  1. Pulse Modulators Frequency Modulators Phase Clocked loops
  2. Frequency Modulators
  3. Phase Clocked loops
  4. All the above

Answer
Answer. d

15. In the Wien Bridge oscillator circuit shown in figure, the bridge is balanced when

  1. $\frac{R_3}{R_4}=\frac{R_1}{R_2}$,$\omega=\frac{1}{\sqrt{R_1C_1R_2C_2}}$
  2. $\frac{R_2}{R_1}=\frac{C_2}{C_1}$,$\omega=\frac{1}{R_1C_1R_2C_2}$
  3. $\frac{R_3}{R_4}=\frac{R_1}{R_2}+\frac{C_2}{C_1}$,$\omega=\frac{1}{\sqrt{R_1C_1R_2C_2}}$
  4. $\frac{R_3}{R_4}+\frac{R_1}{R_2}=\frac{R_1}{R_2}$,$\omega=\frac{1}{R_1C_1R_2C_2}$

Answer
Answer. c