1. An oscillator is a circuit that:
A. Converts DC to AC
B. Converts high-frequency signals to low-frequency signals
C. Generates continuous waveforms without an external signal input
D. Filters AC signals
Answer: C. Generates continuous waveforms without an external signal input
2. The main function of an oscillator is to:
A. Amplify a signal
B. Generate a periodic waveform
C. Filter noise from signals
D. Regulate voltage
Answer: B. Generate a periodic waveform
3. The frequency of oscillation in an RC oscillator depends primarily on:
A. The resistance and capacitance values
B. The inductance and capacitance values
C. The temperature
D. The input power
Answer: A. The resistance and capacitance values
4. The most common type of RC oscillator is the:
A. Hartley oscillator
B. Colpitts oscillator
C. Phase-shift oscillator
D. Crystal oscillator
Answer: C. Phase-shift oscillator
5. In an RC oscillator, the phase shift required for sustained oscillations is:
A. 90 degrees
B. 180 degrees
C. 360 degrees
D. 0 degrees
Answer: B. 180 degrees
6. An important feature of the phase-shift oscillator is that:
A. It uses an inductor and capacitor in the feedback loop
B. It can generate very high frequencies
C. It typically uses three RC stages in the feedback network
D. It is more stable than LC oscillators
Answer: C. It typically uses three RC stages in the feedback network
7. In a Wein-bridge oscillator, the feedback network is made of:
A. Resistor-inductor (RL) network
B. Resistor-capacitor (RC) network
C. Inductor-capacitor (LC) network
D. Capacitor-diode (CD) network
Answer: B. Resistor-capacitor (RC) network
8. In an RC oscillator, the frequency of oscillation is inversely proportional to:
A. The resistance value only
B. The capacitance value only
C. The product of resistance and capacitance
D. The inductance value
Answer: C. The product of resistance and capacitance
9. In an LC oscillator, the frequency of oscillation is determined by:
A. The resistance and capacitance values
B. The inductance and capacitance values
C. The capacitance and inductance only
D. The resistance of the inductor
Answer: B. The inductance and capacitance values
10. The Hartley oscillator is a type of LC oscillator that uses:
A. Two inductors and one capacitor in the feedback loop
B. One inductor and two capacitors in the feedback loop
C. Two capacitors and one inductor in the feedback loop
D. Only one inductor in the circuit
Answer: A. Two inductors and one capacitor in the feedback loop
11. Which type of LC oscillator uses a split capacitor to produce oscillations?
A. Colpitts oscillator
B. Hartley oscillator
C. Clapp oscillator
D. Crystal oscillator
Answer: A. Colpitts oscillator
12. The frequency of oscillation in a Colpitts oscillator is determined by:
A. The inductance and capacitance in the feedback loop
B. The resistance and capacitance in the feedback loop
C. The resistance and inductance in the feedback loop
D. The feedback voltage and the transistor gain
Answer: A. The inductance and capacitance in the feedback loop
13. A crystal oscillator uses a quartz crystal for its:
A. Inductance
B. Capacitance
C. Feedback resistance
D. Mechanical resonance
Answer: D. Mechanical resonance
14. The primary advantage of using a crystal in an oscillator circuit is:
A. Low power consumption
B. Stability and precision in frequency
C. High frequency
D. Low distortion
Answer: B. Stability and precision in frequency
15. In a crystal oscillator, the frequency of oscillation is determined by the:
A. Capacitance of the crystal only
B. Resistance of the crystal
C. Inductance and capacitance of the crystal
D. Mechanical properties of the crystal
Answer: D. Mechanical properties of the crystal
16. Which type of oscillator is commonly used in clocks and frequency control applications?
A. RC oscillator
B. LC oscillator
C. Crystal oscillator
D. Phase-shift oscillator
Answer: C. Crystal oscillator
17. The Pierce oscillator is a type of crystal oscillator that uses:
A. A single crystal and two capacitors in the feedback network
B. A quartz crystal and an inductor in the feedback network
C. A transistor and a capacitor in the feedback network
D. A transistor and two resistors in the feedback network
Answer: A. A single crystal and two capacitors in the feedback network
18. Crystal oscillators are typically used in applications where:
A. High-frequency signals are needed
B. Extremely high stability of frequency is required
C. Low power consumption is the priority
D. Simple design is needed
Answer: B. Extremely high stability of frequency is required
19. In an LC oscillator, the phase shift needed to maintain oscillations is:
A. 0 degrees
B. 90 degrees
C. 180 degrees
D. 360 degrees
Answer: C. 180 degrees
20. Which of the following oscillators is typically used in RF (radio-frequency) applications?
A. Phase-shift oscillator
B. LC oscillator
C. Crystal oscillator
D. RC oscillator
Answer: B. LC oscillator