When the top of the output voltage wave is cut down in an amplifier whose phase shift between input and output is 180〫, it means that () distortion occurred.
A. cutoff
B. saturation
C. crossover
D. frequency
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A simple capacitor filter fed by a full-wave rectifier develops 14.5 V dc at 8.5% ripple factor. The output ripple voltage (rms) is
A. 12V
B. 14.5V
C. 1.2V
D. None of them
To implement a voltage amplifier, () feedback should be introduced.
A. voltage-series negative
B. voltage-shunt negative
C. current-series negative
D. current-shunt negative
Which state is wrong ()?
A. Series feedback connections tend to increase the input resistance; while, shunt feedback connections tend to decrease the input resistance.
B. Shunt feedback connections tend to decrease the input resistance and voltage feedback tends to decrease the output impedance.
C. Voltage feedback tends to decrease the output impedance, while, current feedback tends to increase the output impedance.
D. Series feedback connections tend to increase the input resistance and the current feedback tends to decrease the output impedance.
In the oscillator, the feedback signal must be ().
A. positive
B. negative
C. positive or negative.
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