76. What is the typical value of quality factor for crystal oscillators?
(a) 20,000
(b) 1000
(c) 100
(d) 10
77. A feedback amplifier has a ________ upper 3-dB frequency and a ________ lower 3-dB frequency compared to an amplifier without feedback.
(a) smaller, higher
(b) higher, smaller
(c) smaller, smaller
(d) higher, higher
78. For a phase-shift oscillator, the gain of the amplifier stage must be greater than ________.
(a) 19
(b) 29
(c) 30
(d) 1
79. In the Wien bridge oscillator, which of the following is (are) frequency-determining components?
(a) R1 and R2
(b) C1 and C2
(c) R1, R2, C1, and C2
(d) None of the above
80. In the IC phase-shift oscillator, what should the ratio of feedback resistor Rf to R1 be?
(a) Zero
(b) Greater than –29
(c) Less than 29
(d) Any value
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