BJT Amplifiers and Oscillators MCQs

Question 1

Crystal oscillators are often used for providing

Accepted Answer

stable carrier wave in radio transmitters

Answer

square wave output

Answer

triangular wave output

Answer

frequency multiplication

Question 2

If the frequency of incoming rectangular waves in a staircase generator is 100 Hz, the number of steps in the output staircase pattern is

Accepted Answer

200

Answer

100

Answer

500

Answer

50

Question 3

A CB amplifier has very low input resistance because

Accepted Answer

low emitter ac resistance re' shunts all other resistances

Answer

it handles small input signals

Answer

emitter bulk resistance is small

Answer

its base is at ac ground

Question 4

CE amplifier is characterised by

Accepted Answer

signal phase reversal

Answer

low voltage gain

Answer

moderate power gain

Answer

very high output impedance

Question 5

A CC amplifier has the highest

Accepted Answer

current gain

Answer

voltage gain

Answer

power gain

Answer

output impedance

Question 6

In a CC amplifier, voltage gain

Accepted Answer

cannot exceed unity

Answer

depends on output impedance

Answer

is dependent on input signal

Answer

is always constant

Question 7

In a class-A amplifier, conduction extends over 360? because Q-point is

Accepted Answer

centred on load line

Answer

located on load line

Answer

located near saturation point

Answer

located at or near cut-off point.

Question 8

The circuit efficiency of a class-A amplifier can be increased by using

Accepted Answer

transformer-coupled load

Answer

low dc power input

Answer

direct-coupled load

Answer

low-rating transistor

Question 9

The output of a class-B amplifier

Accepted Answer

consists of positive half-cycle only

Answer

is distortion-free

Answer

is like the output of a full-wave rectifier

Answer

comprises short-duration current pulses