17
2-48. What class of biasing does the RC
oscillator use?
1. A
2. B
3. C
4. AB
2-49. In an RC network, (a) what type of
impedance is presented and (b) does the
current lead or lag?
1. (a) Inductive
(b) leads
2. (a) Inductive
(b) lags
3. (a) Capacitive (b) lags
4. (a) Capacitive (b) leads
2-50. In the phase-shift oscillator, a phase shift
of 180 degrees for regenerative feedback
is provided by what minimum number of
RC networks?
1. One
2. Two
3. Three
4. Four
2-51. What determines the phase angle of an RC
network?
1. Input voltage
2. Output voltage
3. Values of resistance and inductance
4. Values of resistance and capacitance
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INTENTIONALLY.
Figure 2D.—Phase-shift oscillator.
IN ANSWERING QUESTIONS 2-52
THROUGH 2-56, REFER TO FIGURE 2D.
2-52. What is the maximum amount of phase
shift provided by Q1 in the figure?
1. 0 degrees
2.
60 degrees
3.
90 degrees
4. 180 degrees
2-53. What type of feedback is provided through
the RC networks to the base of Q1?
1. Neutral
2. Negative
3. Regenerative
4. Degenerative
2-54. At any other than the desired frequency,
what type of feedback is provided by the
circuit?
1. Neutral
2. Positive
3. Regenerative
4. Degenerative
2-55. What components make up the frequency-
determining device?
1. C1, C2, CE, R1, R2, RB
2. C2, C3, CE, R2, RB, RE
3. C1, C2, C3, R1, R2, RB
4. Cout, C1, C2, R1, R2, RE
