61. Which of the following improvements is (are) a result of the negative feedback in a circuit?
(a) Higher input impedance
(b) Better stabilized voltage gain
(c) Improved frequency response
(d) All of the above
62. Which of the following is (are) feedback?
(a) Voltage-series
(b) Voltage-shunt
(c) Current-series
(d) All of the above
63. Nota
64. At what phase shift is the magnitude of βA at its minimum in the Nyquist plot?
(a) 90º
(b) 180º
(c) 270º
(d) 0º
65. Which of the following is required for oscillation?
(a) β A > 1
(b) The phase shift around the feedback network must be 180º.
(c) Both βA > 1 and the phase shift around the feedback network must be 180º.
(d) None of the above
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