Oscillators » Exercise – 2
51. A circuit that can change the frequency of oscillation with an application of a dc voltage is sometimes called ________.
(a) a voltage-controlled oscillator.
(b) a crystal oscillator.
(c) a Hartley oscillator.
(d) an astable multivibrator.
52. Nota
53. Nota
54. Sinusoidal oscillators operate with ________ feedback.
(a) positive
(b) negative
(c) either positive or negative
(d) neither positive nor negative
55. The lead-lag circuit in the Wien-bridge oscillator has a resonant frequency at which the attenuation is ________.
(a) 1/2.
(b) 1/4.
(c) 1/3.
(d) 1/5.
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