1. . In oscillators ________ feedback is used.
(A) Positive feedback
(B) Negative feedback
(C) Both (a) and (c)
(D) Regenerative feedback
2. . The Wien bridge oscillator is used at ________ frequencies.
(A) High
(B) Low
(C) Intermediate
(D) Radio
3. . In Wien bridge oscillator, bridge network has ________ circuit.
(A) Lag network
(B) Lead network
(C) Lead-lag network
(D) Inductive
4. . A lead circuit has a phase angle that is ________?
(A) Greater than 180°
(B) Between 0 and -90°
(C) Greater than 90°
(D) Between 0 and +90°
5. . A lag circuit has a phase angle that is ________?
(A) Between 0 and -90°
(B) Between 0 and +90°
(C) Greater than 90°
(D) Greater than 180°
6. . A Wien bridge oscillator uses ________ feedback.
(A) All of the above
(B) Negative
(C) Regenerative
(D) Positive
7. . Initially, the loop gain of a Wien bridge oscillator is ________?
(A) Unit
(B) Zero
(C) Greater than unity
(D) Less than unity
8. . A Wien bridge oscillator is sometimes called ________.
(A) Notch filter
(B) Twin-T oscillator
(C) Phase shifter
(D) Wheatstone Bridge
9. . RC phase shift oscillator has ________ lead-lag circuits?
(A) Three
(B) Four
(C) Two
(D) One
10. . For oscillations to set up in a circuit, the closed loop gain must be greater than unity and phase shift around the loop must be ________?
(A) 90°
(B) 360°
(C) 270°
(D) 180°
11. . The most widely used LC oscillator is ________?
(A) RC phase shift
(B) Pulse tone
(C) Colpits
(D) Hartley
12. . Link coupling refers to ________ coupling.
(A) Both (a) and (b)
(B) Resistive
(C) Transformer
(D) Capacitive
13. . The Hartley oscillator uses two ________ in LC network.
(A) Inductors
(B) Capacitors
(C) Transistors
(D) Resistors
14. . The Colpits oscillator uses two ________ in LC network.
(A) Resistors
(B) Inductors
(C) Transistors
(D) Capacitors
15. . The material with piezoelectric effect is ________.
(A) Quartz
(B) All of the above
(C) Tourmaline
(D) Rochelle salt
16. . Crystals have a ________.
(A) Low Q
(B) High Q
(C) Small inductance
(D) Large resistance
17. . Hartley and Colpits oscillators are types of ________.
(A) RC oscillators
(B) Crystal oscillators
(C) Ramp generators
(D) LC oscillators
18. . Pulse tone oscillator uses ________ multivibrators.
(A) Four
(B) Two
(C) Three
(D) One
19. . RC phase shift oscillator produces ________ wave.
(A) Triangular
(B) Square
(C) Sinusoidal
(D) Saw tooth
20. . The main property of crystal oscillator is its ________.
(A) Stability
(B) Reliability
(C) Economy
(D) High frequency
21. . The pulse width out of a one-shot multivibrator increases when ________.
(A) Supply voltage increases
(B) Timing capacitance increases
(C) UTP decreases
(D) Timing resistor decreases
22. . The output waveform of 555 timer is ________.
(A) Sinusoidal
(B) Rectangular
(C) Triangular
(D) Elliptical
23. . The quantity that remains constant in a pulse width modulator is ________.
(A) Period
(B) Pulse width
(C) Duty cycle
(D) Space
24. . The kind of oscillator found in an electric wristwatch is the ________.
(A) Wien bridge
(B) Quartz crystal
(C) Hartley
(D) Colpits
25. . An astable 555 timer has ________ stable states.
(A) Zero
(B) One
(C) None of the above
(D) Two