DIPLOMA IN ELECTRONICS AND INSTRUMENTATION ENGINEERING

DIPLOMA IN ELECTRONICS AND INSTRUMENTATION ENGINEERING

SCHEME OF INSTRUCTIONS AND EXAMINATIONS

(FIRST YEAR)
Subject Code
Name of the Subject
Instruction
period / week
Total Period / year

Scheme of Examination

Theory
Practical/Tutorial
Duration (hours)
Sessional Marks
End Exam Marks
Total
Marks
THEORY:

EI-101

English

3
-
90
3
20
80
100

EI-102

Mathematics - I
5
-
150
3
20
80
100

EI-103

Engineering Physics
4
-
120
3
20
80
100

EI-104

Engineering Chemistry and Environmental Studies
4
-
120
3
20
80
100

EI-105

Electronics Components and Materials
3
-
90
3
20
80
100

EI-106

Basic Electrical Engineering
5
-
150
3
20
80
100
PRACTICAL:

EI-107

Engineering Drawing

-
6
180
3
40
60
100

EI-108

Electronics Components and Materials Lab

6
180




EI-109A

Physics Lab

3
45
20
30
50

EI-109B

Chemistry Lab


45
20
30
50

EI-110

Computer Fundamentals lab

3
90
3
40
60
100
TOTAL
24
18
1260

280
720
1000

ELECTRONIC COMPONENTS AND MATERIALS
Subject Title              :           Electronic Components and Materials
Subject Code             :           EI-105
Periods/Week            :           04
Periods/Year              :           120

                                                             TIME SCHEDULE                                                            

S. No
Major Topics
No. of  period
Weightage of marks
Short Answer Questions
Essay Questions
1
Resistors
20
16
2
1
2
Capacitors
20
16
2
1
3
Inductors
15
13
1
1
4
Switches and Relays
15
13
1
1
5
Microphones & Loud speakers
15
13
1
1
6
PCBs
15
13
1
1
7
Electronics Engineering Materials
10
13
1
1
8
Insulating & Magnetic Materials
10
13
1
1
Total
120
110
10
8
OBJECTIVES: On completion of the study of the subject a student should be able to
Comprehend the following.
1.0            Identify working and constructional details of different types of resistors
and their Uses
1.1        Define the property of resistance.
1.2        Classify types of resistors.
1.3        Derive the relation R=ρl/a
1.4        List the specifications of a resistor, and state their importance.
1.5        Explain the necessity of preferred values in resistor.
1.6        Identify Resistance Value by using Colour Code.
1.7        Find the equivalent resistance when two resistors are connected in series.
1.8        Find the equivalent resistance when two resistors are connected in parallel.
1.9        Simple problems on series and parallel connected resistors.
1.10     Compare the features of carbon film metal film (thick and thin) and wire wound resistors with respect to size, power rating, tolerance, temperature coefficient and applications
1.11     Describe constructional details of carbon and wire wound potentiometers.
1.12     Compare the features of carbon and wire wound potentiometers
1.13     Mention the need for tapering in potentiometers.
1.14     Describe the working of rheostat and mention its application.
1.15     Define Positive Temperature coefficient and Negative Temperature coefficient.
1.16     Explain the effects of temperature on resistance.
1.17     Define temperature co-efficient of resistance and deduced the relation   Rt=Ro(1+αot)
1.18   List the common faults in resistors.
2.0 Familiarise with different types of capacitors used in electronic circuits and their applications
2.1        Define the term capacitance.
2.2       Classify the types of capacitors.
2.3       List the specifications of a capacitor and state their importance
2.4       State the factors affecting the capacitance of a   capacitor.  
2.5      Define Di-electric constant and Di-electric strength of a material.
2.6      State the properties, range of values and applications of paper, mica, glass, polyester, polystyrene, ceramic (different types) and electrolytic (different types) capacitors.
2.7       State different types of variable capacitors and mention their applications.
2.8       State losses in capacitors.
2.9       Find equivalent capacitance of Capacitors connected in i) series, and ii) parallel and simple problems.
2.10     List the common faults in capacitors.

3.0  Familiarise with different types of inductors used in electronic circuit  and their applications
3.1    Define self-inductance, mutual inductance and coefficient of coupling.
3.2    Draw the symbols of iron core, air core, and ferrite core inductors.
3.3    Classify inductors.
3.4    List the specifications of inductors.
3.5    List the various core materials used in the construction of inductors.
3.6    Find equivalent inductance when they are connected in series aiding and opposing.
3.7    Find equivalent inductance when they are connected in parallel aiding and opposing.
3.8    Describe the construction features and applications of A.F. and R.F chokes.
3.9    Simple problems on self inductance, mutual inductance and coefficient of coupling.

4.0  Familiarise with different types of switches, Connectors and Relays.

4.1        Define a switch.
4.2        Classify switches according to poles and throws  (SPST, SPDT, DPST,DPDT, Multi-pole multi-throw).
4.3        Explain the working of toggle, push button, rotary, slider, keyboard, and thumb wheel switches with a mention their ratings and applications.
4.4        Sketch the I.S.I symbols of SPST, SPDT, DPST, DPDP, Multi-pole multi throw switches.
4.5        State the need of fuse in electronic equipment.
4.6        Mention different types of fuses.
4.7        Mention the ratings of fuse.
4.8        Explain the necessity of connectors in electronic circuits.
4.9        List different types of connectors.
4.10     Mention the use of MCB.
4.11     Define a relay.
4.12    Classify different relays based on principle of operation, polarization and application.
4.13    Mention specifications and applications of relays.
4.14    Explain the construction & working of general-purpose electromagnetic relay.
4.15    Explain the performance characteristics of relay.
4.16    List the contact materials used in relays and list their characteristics.

5.0 Familiarise different types of microphones and loud speakers.
5.1     Define Microphone.
5.2     List the different types of microphones based on impedance, polar characteristics and principle of working.
5.3     Explain the working of carbon, condenser, Crystal, ribbon and dynamic microphones along with their polar characteristics.
5.4     Mention the specifications of microphones.
5.5     Define Loudspeaker.
5.6     Explain the constructional features and principle of operation of PMMC Loudspeaker and its ratings.
5.7      Mention the necessity of Baffle for a Loudspeaker and list the types of Baffles (like open, infinite, bass reflex, acoustic labyrinth).
5.8      Mention the use of woofers and tweeters.
5.9      Give the need for a Horn loud speaker.
5.10    Compare the performance of characteristics of cone type and horn type loud    speakers.
5.11    Explain the principle of magnetic and crystal headphones and their uses.
5.12    Mention the specifications of Loudspeaker.

6.0  Comprehend PCB materials and their fabrication
6.1        Explain the need of PCB in electronic equipment.
6.2        Classify PCBs.
6.3        List types of laminates used in PCBs.
6.4        Mention the methods of layout preparation of PCB.
6.5        List the methods of transferring layout on the copper clad sheet.
6.6        List the steps involved in screen-printing for making PCBs.
6.7        List the materials used in screen-printing.
6.8        Describe the photo processing techniques for PCB preparation.
6.9        Mention the methods of etching, cleaning and drilling of PCB.
6.10     Describe the steps involved in making double-sided PCB.
6.11     List the materials used in soldering.
6.12     List the soldering methods of PCBs.
6.13     State the standard PCB specification.
6.14      

7.0  Understand Electronics Engineering Materials.
7.1        Classify materials.
7.2         Classify solids.
7.3        Explain the atomic structure.
7.4         Give the properties of conductors.
7.5        List the conducting materials.
7.6        List the mechanical properties of conductors.
7.7         Give the properties of semiconductors.
7.8        Explain the general properties like conductivity, Resistivity.
7.9        Define super conductivity.
7.10     List the examples for superconductors.

8.0  Understand Insulating Materials.
8.1        Define Insulating material.
8.2        Give the properties of insulating materials.
8.3        Classify insulating materials.
8.4        Explain thermoplastics and thermosetting plastics and give examples.
8.5        List the properties of Poly Vinyl Chloride(PVC).
8.6        List the applications of PVC.
8.7        Classify magnetic materials.
8.8        List the magnetic materials used in Industries.
8.9        Explain soft magnetic materials with examples
8.10     Explain hard magnetic materials with examples.
8.11     Explain soft ferrites.

COURSE CONTENTS

1.            Resistors: Classification of resistors, colour code, Specifications, preferred values of resistors, their properties and uses – Carbon film metal film wire wound resistors, characteristics and applications. Constructional details of carbon and wire wound Potentiometers - tapering. Effect of temperature on resistance. faults in resistors.

2.            Capacitors: Classification, specifications of capacitors, dielectric constant, dielectric strength, properties and applications of paper, mica, ceramic polyester, polystyrene, glass and electrolytic capacitors. Variable capacitors and applications, capacitor connected in series and parallel.

3.            Inductors : Self Inductance, mutual inductance, coefficient of coupling, A.F. and R.F. chokes.

4.            Switches, connectors and Relays: Different types of switches and connectors used in Electronic circuits, their specifications, constructional details and ratings. Fuses. Types of relays-Relay contacts, constructional features of relays.

5.            Microphones and Loudspeakers: Types of microphones – carbon, condenser, ribbon, moving coil, and crystal. Constructional features, principle of working, characteristics, construction of PMMC Loudspeakers, Baffles, horns and head phones.

6.            PCBs: Classification of PCBs, screen-printing of PCBs, photo processing, double sided PCBs, soldering methods of PCBs, standard PCB specifications.
7.            Electronic Engineering materials: Materials-Classifications-Solids-Atomic Structure-Conductors and semi conductors and their properties-super conductivity-examples
8.            Insulating materials : Insulating materials- properties- classification. Thermoplastics, Thermosetting plastics, PVC Properties & applications- Magnetic materials, examples. Ferrites.

Reference Books

1.    Electronic devices and applications by B. Soma Nathan Nair, PHI.
2.    Principles of Electronic Communications by AnokSingh (For speakers & Microphones)
3.    Electronic components      by       Dr.K.Padmanabham.
4.    Electronic Instruments and Systems by B.P Gupta TMH
5.    Principles of Electronics by V.K.Mehatha
6.    P.C.Bs                                 by      Boshart, TMH
7.    Basic Electronics                by      Grob.,              TMH
8.    Electronic devices & Circuits  by Millman & Halkias, TMH
9.    Fundamentals of Acoustics   by   Lawrence & Frag.
10.  Electronic Components     by       F.J. Waters.



























BASIC ELECTRICAL ENGINEERING

Subject Title              :           Basic Electrical Engineering
Subject Code             :           EI-106
 Periods/Week           :           04
 Periods/Year             :           120

            TIME SCHEDULE

Sl. No.
Major Topics
Periods
Weightage
Short questions
Essay questions
1.
Basic principles of Electricity
22
16
2
1
2.

Work, Power & Energy

08
13
1
1
3.
Heating effects of electric Current
14
13
1
1
4.
Magnetic effects of Electric current
22
21
2
1 ½
5.
Electromagnetic Induction
20
16
2
1
6.
Electrostatics 
20
18
1
1 ½
7
Batteries
14
13
1
1

Total
120
110
10
8

                                                                                
OBJECTIVES
Upon completion of the course the student shall be able to
1.0        Comprehend the Basic principles of electricity
               1.1     Explain structure of atom , electron configuration of elements.
1.2      Define Valence electron; distinguish between Conductors, Insulators and Semiconductors with reference to valence electrons.
1.3      Explain the concept of electric charge, state  SI unit for charge.
1.4      Explain the concept of potential, potential difference and E.M.F.. Mention their S.I. Units.
1.5      Explain the concept of electric current and differentiate between conventional electric current and electron current.
1.6      State and explain Ohm’s law.
1.7      Explain the concept of electrical Resistance and Conductance and mention their S.I. Units
1.8      State the parameters affecting the resistance.
1.9      Define specific resistance and state its S.I. Unit.
1.10   Explain temperature Coefficient of resistance and solve simple problems on variation of resistance with temperature.        
1.11   Derive the formula for equivalent resistance when resistances are connected in series, parallel and series-parallel.
1.12   Solve problems on series, parallel and series-parallel circuits for total current, branch current, power, and p.d. across and in part of the circuit.


2.0          Explain the concept of Work, Power & Energy
2.1       Explain the concepts of work done, energy expended and power dissipated in electric circuit and state  S.I. Units of  Work, Power and Energy
2.2          Express Work, Power and Energy in Electrical, Mechanical and Thermal Units.
2.3           Define Efficiency.
2.4          Calculate electricity bill for domestic consumers.
2.5          Solve problems on work, power and energy in Electrical, Mechanical and Thermal units.

3.0          Appreciate the Heating effects of Electric Current
3.1       Explain the Mechanical equivalent of heat.
3.2       State the heat produced due to flow of current.
3.3       Explain the practical applications of heat produced due to Electric current in metal
Filament lamps, Electric kettle, Electric cooker, Electric Iron, Space heaters, Geyser,Infrared lamp.
3.4       Define Thermal efficiency.
3.5       Solve problems on the above.

4.0          Appreciate the Magnetic effects of Electric Current
4.1       Draw the lines of force around a magnet
4.2       Explain the concept of field lines around current carrying conductors
4.3       State Right Hand Thumb rule.
4.4       Plot the field pattern due to
a) Straight current carrying conductor
            b) Solenoid and
c) Toroid.
4.5  Explain Work law and its applications.
4.6       State Laplace law (Biot-Savart’s Law)
4.7       Give expressions for field strength (No derivation)
a)    Around a Straight conductor
b)    At the Centre of a circular conductor
c)    At any point on the axis of a circular conductor
d)    On the axis of a solenoid
4.8       Explain the Mechanical force on a current carrying Conductor placed inside a Magnetic field.
4.9       Derive an expression for the magnitude of force on a conductor placed  inside a magnetic field.
4.10     State the Fleming’s Left Hand rule
4.11     Derive an expression for the force between two parallel current carrying conductors.       
4.12     State the nature of the force with different current directions in parallel conductors
4.13     Define Ampere
4.14     Solve problems on the above.
4.15     Define magnetizing Force, Permeability, Flux and Reluctance
4.16     Derive the concept of Magnetic circuits
4.17     Solve problems on simple magnetic circuits
4.18     Compare Magnetic circuit with Electric circuit.
4.19State Magnetic leakage co-efficient.
5.0       Explain Electro Magnetic Induction
5.1       State Faraday’s laws of Electro - Magnetic Induction.
5.2       Explain Dynamically and Statically induced E.M.F.
5.3       State Lenz’s law and explain Fleming’s Rright Hand rule.
5.4       Explain the concept of Self and Mutual inductance.
5.5       Derive expressions for Self and Mutual inductance.
5.6       State co-efficient of coupling.
5.7       Explain the total inductance with series connections with reference to direction of flux.
5.8       Develop an expression for the energy stored in a magnetic field.
5.9       Develop an expression for the energy stored per unit volume
5.10     Develop an expression for Lifting power of a magnet.
1.1  Solve problems on the above.

6.0       Comprehend Electric Charge and Electrostatic Field
6.1       State Coulomb’s laws of electrostatics and define unit charge
6.2       Define Absolute and Relative permittivity.
6.3       Solve problems on the above
6.4       Explain electrostatic field.
6.5       Plot electrostatic field due to
a)     Isolated positive charge
b)     Isolated negative charge
c)     Unlike charges placed side by side
d)    Like charges placed side by side
6.6       State electric Flux, electric Flux density and Field intensity.
6.7       Compare Electrostatic and Magnetic circuits.
6.8       State Gauss theorem.
6.9       Explain electric potential and potential difference.
6.10     Explain Di-electric strength and Di-electric constant
6.11     Define Capacitance and state its unit.
6.12     Derive the formula for capacitance of a capacitor.
6.13     State different types of capacitors
6.14     Give uses of different capacitors
6.15     Explain equivalent capacitance of
a)     Capacitors connected in series;
b)     Capacitors connected in parallel
6.16     Derive an expression for the energy stored in a capacitor
6.17Solve problems on the above

7.0 Comprehend the Batteries
7.1        Classify cells as Primary and Secondary cells.
7.2           Compare Primary and Secondary cells. 
7.3        Name the types of storage cells as Lead-Acid, Nickel-Iron and Nickel
       -Cadmium
7.4        Explain the parts of Lead-Acid battery.
7.5        Write chemical reactions during charging and discharging of Lead-Acid
battery.
7.6       List indications of fully charged Lead-Acid battery.
7.7          Explain parts of Nickel – Iron cells
7.8       Write chemical reactions during charging and discharging of Nickel – Iron cell.
7.9        State applications of (a) Lead-Acid battery (b) Nickel-Iron cell
(c) Nickel-Cadmium battery.
7.10      Compare Lead-Acid cell with Nickel-Iron cell.
7.11     Explain charging of batteries by Constant Current method and Constant Voltage method.
7.12     State precautions to be taken during charging & discharging of        batteries.
7.13     Explain Trickle charging
7.14     State capacity of a battery and factors affecting capacity.
7.15     Define maintenance free battery
7.16     Differentiate between maintenance free batteries and lead-acid batteries
7.17     Explain the construction and working of maintenance free batteries
7.18     State the applications of maintenance free batteries.


COURSE CONTENT


1.    Comprehend the Basic principles of electricity:
Atomic Structure, Differences conductors, Insulators and semiconductors, Concept of Electric charge, Concept of Potential, Concept of Electric Current. Ohms law, Concept of Electrical resistance, parameters affecting resistance, Specific resistance, temperature coefficient, Work Power and Energy, Series, parallel and Series-Parallel circuits.
     
2.    Work, Power & Energy
Units of Work, Power and Energy. – Conversion of Units-Efficiency

3.    Heating Effects of Electrical Current  
Mechanical Equivalent of Heat - Heat produced due to flow of current in resistance- Applications

4.    Magnetic Effects of Electric Current
Lines of force - Field pattern due to long straight current carrying conductor-Field pattern of solenoid and Toroid -Work Law and its applications -Biot Savart Law(Laplace Law) -Field strength at centre and any point on the axis of a circular current carrying conductor- Field Strength around a straight current carrying conductor- Field strength on the axis of a solenoid-Mechanical force on a current carrying conductor placed inside a magnetic field -  Direction of force -  Fleming’s  Left Hand rule -Force between two parallel current carrying conductors – Ampere - Magnetic circuit-  Magnetising force – Permeability - Flux - Reluctance - Comparison of Magnetic circuit with electric circuit - Magnetic leakage.

5.    Electro Magnetic Induction
Faraday’s laws - Dynamically and Statically induced E.M.F -Lenz’s Law & Fleming’s Right Hand rule -Self and Mutual inductance - Co-efficient of coupling - Inductances in series -Energy stored in a magnetic field - Energy stored per unit volume - Lifting power of magnet
6.    Electrostatics
Atom, Ion, Positive and Negative charges -Laws of Electrostatics – Coulomb - Permittivity - Electrostatic induction -Electrostatic field - Lines of force -Comparison of Electrostatic and Magnetic lines of force - Strength of electric field- Flux density -Gauss theorem - Electric potential  - potential difference –Di-electric strength – Di-electric constant - Capacitance –Capacitor types - Capacitors in series and parallel- Energy stored in a capacitor.
7.  Batteries
Primary cell and Secondary cell – Lead-Acid, Nickel-Iron and Nickel-Cadmium-Chemical reactions during charging and discharging  –  Charging of Batteries- Constant Current method and Constant Voltage method-Trickle charging - Capacity of Battery-  Maintenance free batteries

REFERENCES

1.     Electrical Technology Vol.I   by B.L.Theraja
2.     Basic Electrical Engineering by T.K.Nagsarkar & M.S.Sukhija – Oxford.
3.     Electrical Technology by Hughes
4.     Electrical Techology Vol.I by J.B.Gupta
5.     Elements of Electrical Engineering by G.B.Bharadhwajan & A. Subba Rao.
6.     Basic Electrical Engineering by D C Kulshreshtha.
7.   Theory and Problems of Basic Electrical Engineering by D.P.Kothari & I.J.Nagarath-PHI
8.   Basic Electrical Engineering by Abhijit Chakrabarthi,Sudipta nath, Chandan Kumar Chada.














ELECTRONIC COMPONENTS LAB


Subject Title                          :           Electronic Components Lab
Subject Code                         :           EI-108
Periods/Week                        :           06
Periods/Year                          :           180

 

TIME SCHEDULE


Major Topic
No. of Periods
1
Identification of components
35
2
Soldering Practice
40
3
Study and use of Electronic equipment
40
4
Testing of Electronic components & characteristics
40
5
Wiring practice
35
Total
180


OBJECTIVES: Upon completion of the subject the student shall be able to

1.0       Identification of components
1.1                Identify different types resistors with different wattage
1.2                Identify different types capacitors with different wattage
1.3                Identify different types Inductors
1.4                Identify colour coding of different resistors
1.5                Identify different types of switches and relays
1.6                Identify microphones and loudspeaker connections
2.0       Soldering                  
2.1        Get familiarised to use of various soldering tools, Components & different cables.
2.2        Assemble and disassemble components using soldering irons.
2.3        Use different types of soldering irons.
2.4        Use solder squeezer on electronic PCBS.
2.5        Use instant soldering gun.
2.6        Solder on printed circuit boards using passive and active components.

3.0          Study and use of electronic equipment
3.1        Familiarise with the symbols of electronic circuit components by drawing.
3.2        Measurement of AC/DC Voltages and currents using voltmeters and current meters.
3.3        Measurement of voltages, currents and resistance using analogue and digital multimeters and continuity test.
3.4        Study and use of AF / RF signal generators.
3.5        Study and use of C.R.O. (single trace & Dual trace) for measuring frequency and amplitude.
3.6        Study and use various regulated power supply units.

4.0          Testing of electronic components
4.1      Measure the value of resistor using ohmmeter / multimeter and compare with the colour code value.
4.2      Test and measure the value of capacitor using R.L.C. meter and compare with the marked / colour code value.
4.3                    Test the given transformer and measure primary and secondary D.C. resistance & Voltages by using multimeter.
4.4                    Test the given loud speaker and measure the voice coil resistance-using multimeter.
4.5                    Test the working of different types of switches, relays, connectors and cables.

5.0          Wiring Practice.
5.1      Familiarise with various tools used in electric wiring.
5.2      Fundamentals of house wiring. Types of wiring and types of wires used for light points and power points.
5.3      Study of different types of switches used in electrical wiring.
5.4      Connection of one lamp with switch.
5.5      Simple staircase wiring – one lamp control with two switches.
5.6      Connection of tube light with function of choke, tube and starter.
5.7      Connection of ceiling fan and reversing the direction of ceiling fan.

Reference Lab Manual:
1.       Electronic Devices and Circuits by David A Bell 4 Edition PHI
2.       Hand soldering and circuit board repair by H.(Ted)Smith, Thomas Delmar.
3.       Electronic instruments and systems – principles, maintenance and troubleshooting. by R.G. Gupta.
4.        


     






Rationale: Electronics Components lab as the student is expected to understand and demonstrate
  practical skills in handling,identifying and using different instruments and various electronic components
with ease. Emphasis is laid on imparting essential skills that required for subsequent learning.
List of Experiments with Objectives and Key competencies
S.NO
Name of the Experiment
Objectives
Key Competencies
1
 Identification of resistor
 Identification of resistor
Identification of resistors
2
Identification of capacitor
Identification of capacitor
Identification of capacitors
3
Identification of inductor
Identification of inductor
Identification of inductors
4
 Identification of different types of switches and relays
 Identification of different
types of switches and relays
Identification of different types of switches and relays
5
Identification of microphones
and loudspeaker connections
Identification of microphones
 and loudspeaker connections
Identification of microphones and loudspeaker connections
6
Soldering
soldering tools, Components
 & different cables.
Soldering tools, components & different cables
7
Soldering
Assembly and disassembly
components using soldering irons
Assembly and disassembly components using soldering irons
8
Soldering
Different types of soldering irons
Different types of  soldering irons
9
Soldering
Solder on printed circuit boards using passive and active components
Practicing of soldering with different components on pcb
10
Soldering
Use instant soldering gun.
understanding the usage of soldering gun
11
Soldering
solder squeezer on electronic
 PCBS
practice the removal of components on PCB using soldering iron
12
Study and use of electronic equipment
 Familiarise with the symbols of
 electronic circuit components by drawing.
Identify the symbols used in electronic circuits
13
Study and use of electronic equipment
Measurement of AC/DC Voltages and currents using voltmeters and ammeters
To measure theAC/DC voltages currents using voltmeters and ammeters
14
Study and use of electronic equipment
Measurement of voltages, currents and resistance using analogue and digital multimeters and continuity test.
To measure the voltages currents and resistance using analog and digital multimeters
15
Study and use of electronic equipment
 Study and use of
AF / RF signal generators.
Understanding the wave forms of AF/RF signal generators
16
Study and use of electronic equipment
Study and use of C.R.O.
(single trace & Dual trace) for
measuring frequency and amplitude.
To calculate the frequency and amplitude of given waveform in cro
17
Study and use of electronic equipment
Study and use various regulated power supply units.
Studied various regulated
 power supply units


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