BJT Amplifiers and Oscillators MCQs

Question 1

Super-n transistor is a

Accepted Answer

Darlington configuration

Answer

matched pair

Answer

cascade configuration

Answer

cascode configuration

Question 2

Which of the following is a disadvantage of directly coupled transistor amplifier?

Accepted Answer

Variations in current due to temperature changes in one stage are amplified by other stages

Answer

The low frequency response is poor

Answer

Identical transistor are required

Answer

Both N-P-N transistor are required

Question 3

Which of the following statements is correct in case of a CE configuration transistor amplifier?

Accepted Answer

No phase change between input and output currents

Answer

No phase change between input and output voltages

Answer

1800 phase change between input and output currents

Answer

None of the above

Question 4

The high cut-off frequency on the pole-zero diagram of an amplifier is determined by the

Accepted Answer

pole close to the origin

Answer

zero closest to the origin

Answer

zero farthest from the origin

Answer

pole farthest from the origin

Question 5

___ configuration has invariably high cut-off frequency.

Accepted Answer

CB

Answer

CE

Answer

CC

Answer

All of the above

Question 6

The bandwidth of a difference amplifier is comparable to that of a

Accepted Answer

cascade amplifier

Answer

Darlington amplifier

Answer

single-stage CE amplifier

Answer

double-stage CE amplifier

Question 7

A push-pull amplifier requires which of the following?

Accepted Answer

Equal input voltages with 1800 out of phase

Answer

An output transformer with a centre-tap in the secondary

Answer

Equal input voltages in phase

Answer

Equal input voltages with 90? out of phase

Question 8

____has the lowest efficiency.

Accepted Answer

Class A

Answer

Class B

Answer

Class C

Answer

Class AB

Question 9

Which of the following statements regarding transformer-coupled amplifiers is correct?

Accepted Answer

D.C. load line is nearly vertical

Answer

A.C. load line is nearly vertical

Answer

Both load lines are nearly horizontal

Answer

None of the above