EASY PSC | Technician Grade II (Electronics)

Question 1

Removing bypass capacitor across the emitter-leg resistor in a CE amplifier causes:

A

Increase in current gain

B

Decrease in current gain

C

Increase in voltage gain

D

Decrease in voltage gain

Question 2

The breakdown mechanism in a lightly doped p-n junction under reverse biased condition is called:

A

Avalanche breakdown.

B

Zener breakdown.

C

Breakdown by tunnelling

D

High voltage breakdown

Question 3

BIOS means:

A

Binary input/output service

B

Basic input/output system

C

Basic information of system

D

None of these

Question 4

A network configuration in which each computer is attached to a central unit is called a ………….. network.

A

Star

B

Bus

C

Hybrid

D

None of these

Question 5

In an intrinsic semiconductor, the Fermi-level is:

A

Closer to the valence band

B

Midway between conduction and valence band

C

Closer to the conduction band

D

Within the valence band

Question 6

Data is transmitted using light through a ……………. cable.

A

Twisted pair

B

Fiber-optic

C

Coaxial

D

Microwave

Question 7

An oscillator of the LC type that has a split capacitor in the circuit is:

A

Hartley oscillator

B

Colpitts oscillator

C

Weinbridge oscillator

D

R-C phase shift oscillator

Question 8

After the magnetizing force has been removed, the ratio of the remaining magnetic flux to the saturated magnetic flux is called:

A

Saturation

B

Retentivity

C

Hysterisis

D

Coercivity

Question 9

The shape of warning sign is:

A

Triangular

B

Square

C

Circular

D

Oblong

Question 10

If a voltmeter marked in volts is used to measure a 3500 milli volt potential, what reading would it show?

A

3.5 volts

B

0.35 volt

C

35 volts

D

350 volts

Question 11

In a series resonant circuit at resonance, the circuit has:

A

low mutual inductance

B

high impedance

C

low impedance

D

high mutual inductance

Question 12

HDTV stands as :

A

High Definition Television

B

Half Definition Television

C

Huge Definition Television

D

None of these

Question 13

A circuit designed to increase the level of its input signal is called:

A

A receiver

B

A modulator

C

An oscillator

D

An amplifier

Question 14

In a Yagi-Uda 3 element directional antenna, the …………… is the longest radiating element.

A

Director

B

Driven element

C

Reflector

D

None of these

Question 15

The connecting leads in an IC chip are made of:

A

Aluminium

B

Silicon

C

Calcium

D

None of these

Question 16

A type of memory chip whose contents can be quickly changed by the computer at any time is called:

A

VDT

B

RUM

C

ROM

D

RAM

Question 17

The NAND gate output will be low if the two inputs are:

A

00

B

01

C

10

D

11

Question 18

A flip-flop has two outputs which are:

A

Always zero

B

Always one

C

Always complementary

D

In one of the above states

Question 19

Primary source of power for satellite is:

A

lead acid battery

B

nickel-cadmium battery

C

solar cells.

D

regulated power supply

Question 20

Which of the following is the fastest logic?

A

TTL

B

ECL

C

CMOS

D

LSI

Question 21

How many flip flops are required to construct a decade counter?

A

10

B

3

C

4

D

2

Question 22

A universal logic gate is one, which can be used to generate any logic function. Which of the following is a universal logic gate?

A

OR

B

AND

C

XOR

D

NAND

Question 23

A full adder logic circuit will have:

A

Two inputs and one output

B

Three inputs and three outputs

C

Two inputs and two outputs.

D

Three inputs and two outputs

Question 24

The 2”s complement of the number 1101110 is :

A

0010001

B

0010011

C

0010010

D

None of these

Question 25

A watt-hour meter measures:

A

Energy

B

Current

C

Voltage

D

Power

Question 26

The Schmitt trigger circuit behaves as a :

A

Triangular wave generator

B

Mono stable multi vibrator

C

Bi-stable multi vibra

D

Free running multi vibrator

Question 27

Satellite communication works through:

A

Radar

B

Transponder

C

Receptor

D

None of these

Question 28

The fourth color band on a resistor mean:

A

The value of the resistor in ohms

B

The power rating in watts

C

The resistance material

D

The resistance tolerance in percent

Question 29

MPEG stands as:

A

Moving Pictures Expert Group

B

Most Pictures Expert Group

C

Moving Pictures Enhance Group

D

None of these

Question 30

In our TV system, which system is being followed?

A

PAL

B

NTSC

C

SECAM

D

None of these.

Question 31

What is a coaxial cable?

A

Two wires side-by-side in a plastic ribbon

B

Two wires side-by-side held apart by insulating rods

C

Two wires twist around each other in a spiral

D

A center wire inside an insulating material which is covered by a metal sleeve or shield

Question 32

Wien bridge oscillator can typically generate frequencies in the range of:

A

1 KHz-1 MHz

B

1 MHz-10 MHz

C

10 MHz-100 MHz

D

100 MHz-150 MHz

Question 33

In a full-wave rectifier without filter, the ripple factor is :

A

1.21

B

0.482

C

1.79

D

2.05

Question 34

The arrangement of the computers in a network is called the :

A

NOS

B

Topology

C

Node layout

D

Protocol

Question 35

Which of the following diodes has a negative-resistance region?

A

Schottky

B

Varactor

C

Power

D

Tunnel

Question 36

N-type silicon is obtained by:

A

Doping with tetravalent element

B

Element Doping with trivalent element

C

Doping with pentavalent

D

Doping with a mixture of trivalent and tetravalent.

Question 37

D-MOSFET can be operated in ……………. mode.

A

saturation

B

depletion

C

enhancement

D

depletion and enhancement

Question 38

What is the phase difference between input and output signal in a CE amplifier?

A

0°

B

45°

C

180°

D

90°

Question 39

The voltage gain of CC amplifier is:

A

Less than 1

B

Greater than 1

C

Equal to 1

D

None of these

Question 40

Which of the following statements is true?

A

FET and BJT, both are unipolar

B

FET and BJT, both are bipolar

C

FET is bipolar and BJT is unipolar

D

FET is unipolar and BJT is bipolar

Question 41

Which of the following amplifiers is known as an emitter follower?

A

CE amplifier

B

CC amplifier

C

CB amplifier

D

Cascade amplifier

Question 42

Power is defined as:

A

The rate at which current flows in a circuit

B

The rate at which energy is radiated or dissipated

C

The accumulation of energy over time

D

The amount of heat generated in a circuit

Question 43

Three equal resistance of magnitude 5 Ohm each are connected in delta. The resistance between any two pair of terminals of the delta will be:

A

5 Ohm

B

5/3 Ohm

C

10/3 Ohm

D

3/5 Ohm

Question 44

The other name for beta of BJT is :

A

Current amplification factor

B

Voltage amplification factor

C

Power amplification factor

D

None of these

Question 45

One coulomb-per second is equal to one:

A

Watt

B

Joule

C

Volt

D

Ampere

Question 46

The reverse saturation current of a silicon diode:

A

Doubles for every 10°C increase in temperature

B

Does not change with temperature

C

Halves for every 1°C decrease in temperature

D

Increases by 1.5 times for every 2°C increment in temperature.

Question 47

In class-A amplifier, the output current flows for :

A

A part of the cycle or the input signal

B

The full cycle of the input signal

C

Half the cycle of the input signal

D

3/4th of the cycle of the input signal

Question 48

For silicon the forbidden gap is :

A

1.1 ev

B

0.25 ev

C

0.5 ev

D

0.7 ev

Question 49

The modulation used in cellular communication is:

A

Amplitude modulation

B

Pulse code modulation

C

Digital modulation

D

Narrow band frequency modulation

Question 50

Manganin is an alloy of:

A

Copper, manganese and nickel

B

Copper and manganese

C

Manganese and nickel

D

Manganese, aluminium and nickel

Question 51

In Quadrature Amplitude Modulation, (QAM), the carrier is modulated by :

A

Amplitude

B

Phase

C

Frequency

D

Both (A) and (B)

Question 52

What are the steps followed to achieve Pulse Code Modulation?

A

Sampling, quantizing, modulation

B

Detecting, sampling, quantizing

C

Sampling, quantizing, coding

D

Coding, modulating, packetizing

Question 53

An ideal power supply is characterized by:

A

Very large output resistance

B

Very small output resistance

C

Zero internal resistance

D

Infinite internal resistance

Question 54

What is the "power factor"?

A

Ratio of true power to apparent power

B

Peak power times 0.707

C

Sin of the phase difference between E and I

D

None of the above

Question 55

A house served by a 220 V supply light, is protected by a 9-Ampere fuse. The maximum number of 60W bulbs in parallel that can be turned on is:

A

11

B

33

C

22

D

44

Question 56

Holes are the minority carriers in which type of semiconductor?

A

Extrinsic

B

Intrinsic

C

N-type

D

None of the above

Question 57

Doubling the number of turns of wire in an inductor:

A

Reduces the value of inductance by one-half

B

Multiplies the value of inductance by two

C

Reduces the value of inductance by one-fourth

D

Multiplies the value of inductance by four

Question 58

Which bus is bidirectional?

A

Data bus

B

Control bus

C

Address bus

D

Multiplexed bus

Question 59

If the input to a comparator is a sine wave, the output is a:

A

Ramp voltage

B

Rectangular wave

C

Sine wave

D

Sawtooth wave

Question 60

Convert the binary number 1011010 to hexadecimal:

A

5A

B

5F

C

5B

D

None of the above

Question 61

A half-cycle average voltage of 12 V is equal to what rms voltage?

A

13.33 V

B

8.48 V

C

18.84 V

D

7.64 V

Question 62

ASCII stands for:

A

American Serial Communication interface

B

Additive Signal Coupling Interface

C

American Standard Code for Information Interchange

D

None of the above

Question 63

How is power dissipated in a resistor?

A

By voltage

B

By heat

C

By current

D

None of the above

Question 64

You can determine the direction of the lines of force surrounding a conductor by using :

A

The left-hand rule

B

The right-hand rule

C

Lenz”s law

D

None of the above

Question 65

Moving iron meter is suitable for measurement of:

A

AC

B

DC

C

AC/DC

D

DC/AC with rectifier

Question 66

The effective value of a sine wave is equal to :

A

0.707 of peak voltage

B

0.636 of peak voltage

C

Sin 45° of peak voltage

D

Both 0.707 of peak voltage and sin 45° of peak voltage

Question 67

How is ac current related to ac voltage in a purely capacitive circuit?

A

AC current is 0.707 of the ac voltage

B

AC current lags ac voltage:

C

AC current is 0.637 of the ac voltage

D

AC current leads ac voltage

Question 68

A basic S-R flip-flop can be constructed by cross-coupling which basic logic gates?

A

AND or OR gates

B

XOR or XNOR gates

C

NOR or NAND gates

D

AND or NOR gates

Question 69

AJFET:

A

Is a voltage-controlled device

B

Has a low input resistance

C

Is a current-controlled device

D

None of the above.

Question 70

When does maximum power transfer happen from the source to the load?

A

When the source resistance is greater than the load resistance

B

When the source resistance is less than the load resistance

C

When there is negligible source resistance

D

When the source resistance equals the load resistance

Question 71

To connect a computer with a device in the same room, you might be likely to use:

A

A coaxial cable

B

A dedicated line

C

All of the above.

D

None of the above

Question 72

Frames from one LAN can be transmitted to another LAN via the device:

A

Router

B

Bridge

C

Repeater

D

None of the above

Question 73

The geostationary satellite used for communication systems:

A

Rotates with the earth

B

Remains stationary relative to the earth

C

Is positioned over equator

D

All of the above

Question 74

High frequency transformers sometimes make use of ferrite cores because it has:

A

High resistance

B

High hysteresis

C

Low permeability

D

None of the above

Question 75

An emitter follower has :

A

High input impedance and high output impedance

B

High input impedance and low output impedance

C

Low input impedance and high output impedance

D

Low input impedance and low output impedance

Question 76

To prepare a P type semiconducting material the impurities to be added to silicon are:

A

Gallium, Arsenic

B

Gallium, Phosphorous

C

Arsenic, Antimony

D

Boron, Gallium

Question 77

The device used for locating open circuits or short circuits in a circuit is:

A

Ammeter

B

Voltmeter

C

Ohm meter

D

None of the above

Question 78

To increase the input resistance and decrease the output resistance in negative feedback, the type used is:

A

Voltage Shunt

B

Current Series

C

Voltage Series

D

Current Shunt

Question 79

A register in the microprocessor that keeps track of the answer or results of any arithmetic or logic operation is the :

A

Stack pointer

B

Accumulator

C

Program counter

D

None of the above

Question 80

The waveform used in X-direction in CRO for deflecting the electron beam from left or right is:

A

Rectangular

B

Triangular

C

Square

D

Saw tooth

Question 81

The machine which transmits documents/maps/photographs over telephone line:

A

Fax

B

Type writer

C

Teleprinter

D

None of the above

Question 82

Tesla is a unit of:

A

Field strength

B

Inductance

C

Flux density

D

None of these

Question 83

The equivalent of 1 micro ampere is :

A

10000A

B

1000A

C

One millionth of an ampere

D

None of the above

Question 84

An affordable technology that uses existing telephone lines to provide high-speed connections is called:

A

ISDN

B

DSL

C

Cable modem

D

Microwave

Question 85

At resonance, the term bandwidth includes all frequencies that allow what percentage of maximum current to flow?

A

50

B

62.3

C

70.7

D

95.3

Question 86

Which of the following is a passive component?

A

Semi-conductor device

B

Capacitors

C

Vacuum tube device

D

All of the above

Question 87

The process by which Impurities are added to a pure semi-conductor is:

A

Doping

B

Drift

C

Diffusing

D

Mixing

Question 88

An ideal operational amplifier has:

A

Infinite output impedance

B

Zero input impedance

C

Infinite bandwidth

D

All of the above

Question 89

A digital-to-analog converter is an application of the :

A

Scaling adder

B

Voltage-to-current converter

C

Non inverting amplifier

D

Adjustable bandwidth circuit

Question 90

A portion of the output that provides circuit stabilization is considered to be:

A

Distortion

B

Negative feedback

C

Open-loop

D

Positive feedback

Question 91

The ratio between differential gain and common-mode gain is called:

A

Amplitude

B

Common-mode rejection

C

Differential-mode rejection

D

None of the above

Question 92

The Schmitt trigger is used for:

A

Peak detection

B

Filtering

C

In put noise rejection

D

Pulse shaping

Question 93

What type of application would use an injection laser diode?

A

A 10BASE-T Ethernet

B

A liquid crystal display

C

A fiber optic transmission line

D

A good flashlight

Question 94

A transducer”s function is to:

A

Convert energy

B

Transmit electrical energy

C

Produce mechanical energy

D

Prevent current flow

Question 95

Which component is considered to be an "OFF" device?

A

Transistor

B

JFET

C

D-MOSFET

D

E-MOSFET

Question 96

In a PLL, to obtain lock, the signal frequency must:

A

Come within the lock range

B

Be less than the capture frequency

C

Come within the capture range

D

Be greater than the capture frequency

Question 97

The U and V colour difference signals have phase difference of:

A

60⁰

B

90°

C

45°

D

180°

Question 98

The sensitivity of oscilloscope is determined by:

A

Horizontal amplifier

B

Sweep oscillator

C

Vertical amplifier

D

C.R.T

Question 99

The frequency of colour subcarrier is:

A

(A)

B

(B)

C

(C)

D

(D)

Question 100

The major difference between ground and virtual ground is that virtual ground is only a :

A

Voltage reference

B

Current reference

C

Power reference

D

None of the above

096/2014 - Technician Grade II (Electronics) - Kerala Co-operative Milk Marketing Federation Ltd