Transformer coupling can be used in______________amplifiers?
(A) Either power or voltage
(B) Only power
(C) Only voltage
(D) None of the above
An AF amplifier is shielded to ________________?
(A) Keep the amplifier cool
(B) Protect from rusting
(C) Prevent induction due to stray magnetic fields
(D) None of the above
The disadvantage of impedance matching is that it _______________?
(A) Gives distorted output
(B) Gives low power output
(C) Requires a transformer
(D) None of the above
The point of intersection of d.c. and a.c. load lines is called________________?
(A) Saturation point
(B) Cut off point
(C) Operating point
(D) None of the above
If a transistor amplifier draws 2mA when input voltage is 10 V, then its input impedance is ____________?
(A) 20 kΩ
(B) 2 kΩ
(C) 10 kΩ
(D) 5 kΩ
The output transformer used in a power amplifier is a _____________ transformer?
(A) 1:1 ratio
(B) Step-up
(C) Step-down
(D) None of the above
The pulsating d.c. applied to power amplifier causes________________?
(A) Burning of transistor
(B) Hum in the circuit
(C) Excessive forward voltage
(D) None of the above
If the gain versus frequency curve of a transistor amplifier is not flat, then there is distortion ?
(A) Amplitude
(B) Intermodulation
(C) Frequency
(D) None of the above
If the power rating of a transistor is 1W and collector current is 100mA, then maximum allowable collector voltage is________________?
(A) 1V
(B) 100V
(C) 20V
(D) 10V
What will be the collector efficiency of a power amplifier having zero signal power dissipation of 5 watts and a.c. power output of 2 watts ?
(A) 20%
(B) 80%
(C) 40%
(D) 50%