NCATT EXAM 2025 QUESTIONS
AND ANSWERS
Negative Temperature coefficient: As temperature increases, resistance..... -
....ANSWER ...-Decreases
Using a swamping resister for thermal stability, what type of feedback is developed
to control the amplifier? - ....ANSWER ...-Degenerative
What dissipates heat into the air? - ....ANSWER ...-Heatsink
What amplifier coupling can amplify DC voltages as well as AC signals? -
....ANSWER ...-Direct Coupler
In a common collector amp, degenerative feedback is how many degrees out of
phase with the input signal? - ....ANSWER ...-180
The common base amplifier has a voltage gain _______ than one, but the current
gain______than one - ....ANSWER ...-Greater. Less.
Sinusoidal Oscillator produces what waveform? - ....ANSWER ...-Sine
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 1
,Requirements for sustaining oscillations in an oscillator - ....ANSWER ...-
Power supply, FDD, Amplifier, Regenerative Feedback
What determines width output pulses in a bistable multivibrator? -
....ANSWER ...-PRT of the input triggers
Bi-stable multvibrator also known as - ....ANSWER ...-Flip-flop/frequency
divider
What type of output wave is created by an astable multivibrator? -
....ANSWER ...-square wave or rectangle wave
Astable multivibrator is a what type of oscillator - ....ANSWER ...-Free
running oscillator
The monostable multivibrator output PRF is determined by the -
....ANSWER ...-input trigger frequency
Transistor amplifier operating in class B, collector current will flow_____of the
input signal? - ....ANSWER ...-180 or 50%
Class A amplifier - ....ANSWER ...-360 or 100%
Class C amplifier - ....ANSWER ...-90 degrees or less than 50%
Class AB amplifier - ....ANSWER ...-More than 180%, less than 360 degrees
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 2
, What type of amplifier coupling is used for impedence matching and circuit
isolation? - ....ANSWER ...-Transformer
The interchange of energy between the inductor and capacitor in a tank circuit is
called - ....ANSWER ...-Flywheel effect
Amplifier class of operation is determined by - ....ANSWER ...-Amount of
forward bias
what is resistance of normally closed contacts when the relay is de-energized -
....ANSWER ...-0 or short
What distinguishes a solenoid from a basic relay? - ....ANSWER ...-Plunger is
pulled into the coil
What part of a basic relay returns the armature to its de-energized position -
....ANSWER ...-Spring
What parts of a relay comprise the primary (control) circuit? -
....ANSWER ...-Core and Coil
What parts of a relay comprise the secondary (controlled) circuit? -
....ANSWER ...-Armature, contacts, and spring
How many paths of current are required for a holding relay coil? -
....ANSWER ...-Two
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 3
AND ANSWERS
Negative Temperature coefficient: As temperature increases, resistance..... -
....ANSWER ...-Decreases
Using a swamping resister for thermal stability, what type of feedback is developed
to control the amplifier? - ....ANSWER ...-Degenerative
What dissipates heat into the air? - ....ANSWER ...-Heatsink
What amplifier coupling can amplify DC voltages as well as AC signals? -
....ANSWER ...-Direct Coupler
In a common collector amp, degenerative feedback is how many degrees out of
phase with the input signal? - ....ANSWER ...-180
The common base amplifier has a voltage gain _______ than one, but the current
gain______than one - ....ANSWER ...-Greater. Less.
Sinusoidal Oscillator produces what waveform? - ....ANSWER ...-Sine
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 1
,Requirements for sustaining oscillations in an oscillator - ....ANSWER ...-
Power supply, FDD, Amplifier, Regenerative Feedback
What determines width output pulses in a bistable multivibrator? -
....ANSWER ...-PRT of the input triggers
Bi-stable multvibrator also known as - ....ANSWER ...-Flip-flop/frequency
divider
What type of output wave is created by an astable multivibrator? -
....ANSWER ...-square wave or rectangle wave
Astable multivibrator is a what type of oscillator - ....ANSWER ...-Free
running oscillator
The monostable multivibrator output PRF is determined by the -
....ANSWER ...-input trigger frequency
Transistor amplifier operating in class B, collector current will flow_____of the
input signal? - ....ANSWER ...-180 or 50%
Class A amplifier - ....ANSWER ...-360 or 100%
Class C amplifier - ....ANSWER ...-90 degrees or less than 50%
Class AB amplifier - ....ANSWER ...-More than 180%, less than 360 degrees
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 2
, What type of amplifier coupling is used for impedence matching and circuit
isolation? - ....ANSWER ...-Transformer
The interchange of energy between the inductor and capacitor in a tank circuit is
called - ....ANSWER ...-Flywheel effect
Amplifier class of operation is determined by - ....ANSWER ...-Amount of
forward bias
what is resistance of normally closed contacts when the relay is de-energized -
....ANSWER ...-0 or short
What distinguishes a solenoid from a basic relay? - ....ANSWER ...-Plunger is
pulled into the coil
What part of a basic relay returns the armature to its de-energized position -
....ANSWER ...-Spring
What parts of a relay comprise the primary (control) circuit? -
....ANSWER ...-Core and Coil
What parts of a relay comprise the secondary (controlled) circuit? -
....ANSWER ...-Armature, contacts, and spring
How many paths of current are required for a holding relay coil? -
....ANSWER ...-Two
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 3
