electronics & communication engineering workshop...

Electronics & Communication Engineering Workshop Manual

Department of Electronics & Communication Engineering

VEMU INSTITUTE OF TECHNOLOGY::P.KOTHAKOTA NEAR PAKALA, CHITTOOR-517112

(Approved by AICTE, New Delhi & Affiliated to JNTUA, Anantapuramu)

Electronics & Communication Engineering Workshop Manual

Name:_____________________________________________

H.T.No:____________________________________________

Year/Semester:______________________________________

Department of Electronics & Communication Engineering

VEMU INSTITUTE OF TECHNOLOGY::P.KOTHAKOTA NEAR PAKALA, CHITTOOR-517112

(Approved by AICTE, New Delhi & Affiliated to JNTUA, Anantapuramu)

JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY ANANTAPUR

I B.Tech. I-Sem (ECE)

(19A04101) Electronics & Communication Engineering Workshop

Course Objectives:

To introduce electronic components, measuring instruments and tools used in electronic

workshop.

To equip with the knowledge of understanding data sheets of electronic components

To give practical experience on soldering the electronic components on a PCB

To introduce EDA tools

To know about the internal parts of a computer, assembling a computer from the parts,

preparing a computer for use by installing the operating system

To provide training on Productivity tools like word processors, spreadsheets,

presentations

To provide knowledge in understanding working of various communication systems Learning

Outcome:

• Students able to learn electrical model for various semiconductor devices and learns the

practical applications of the semiconductor devices

PART A: List of Experiments

(For Laboratory Examination-Minimum of Ten Experiments)

List of Exercises / Experiments:

1. Familiarization of commonly used Electronic Workshop Tools : Bread board, Solder, cables,

relays, switches, connectors, fuses, Cutter, plier, screwdriver set, wire stripper, flux, knife/blade,

soldering iron, de-soldering pump etc.

• Provide some exercises so that electronics hardware tools and instruments are learned to be

used by the students

2. Familiarization of Electronic Measuring Instruments like Voltmeters, Ammeters, multimeter,

LCR-Q meter, Power Supplies, CRO, DSO, Function Generator, Frequency counter.

• Provide some exercises so that electronic measuring instruments are learned to be used by

the students

3. Electronic Components:

Familiarization/Identification of electronic components (Resistors, Capacitors, Inductors,

Diodes, transistors, IC’s etc.) – Functionality, type, size, color coding, package, symbol, cost etc

4. Testing of electronic components like Resistor, Capacitor, Diode, Transistor, ICs etc.

• Compare values of components like resistors, inductors, capacitors etc with the measured

values by using electronic instruments

5. Study of Cathode Ray Oscilloscope (CRO)

• Find the Amplitude and Frequency of a signal

• Measure the Unknown Frequency & Phase difference of signals using Lissajous Figures

6. Interpret data sheets of discrete components and IC’s.

• Write important specifications/ratings of components & ICs and submit it in the form of a

report

7. Introduction to EDA Tools: MULTISIM/PSPICE/TINA schematic capture tool, Learning of

basic functions of creating a new project, getting and placing parts, connecting placed parts,

simulating the schematic, plotting and analyzing the results

• Provide some exercises so that students are familiarized in using EDA tools.

8. Assembling and Testing of simple electronic circuits on breadboards; identifying the

components and its location on the PCB, soldering of the components, testing the assembled

circuit for correct functionality.

9. Familiarization with Computer Hardware & Operating System:

• Identify the internal parts of a computer, and its peripherals. Represent the same in the

form of diagrams including Block diagram of a computer. Write specifications for each

part of a computer including peripherals and specification of Desktop computer. Submit

it in the form of a report.

• Disassemble and assemble the PC back to working condition. Students should be able to

trouble shoot the computer and identify working and non-working parts. Student should

identify the problem correctly by various methods available (eg: beeps). Students should

record the process of assembling and trouble shooting a computer.

• Install Operating system on the computer. Students should record the entire installation

process.

10. Familiarization with Office Tools

• Word Processor: Able to create documents using the word processor tool. Students

should be able to prepare project cover pages, content sheet and chapter pages at the end

of the task using the features studied.

• Spreadsheet: Able to create, open, save the application documents and format them as

per the requirement. Some of the tasks that may be practiced are Managing the worksheet

environment, creating cell data, inserting and deleting cell data, format cells, adjust the cell size,

applying formulas and functions, preparing charts, sorting cells.

• Presentations: creating, opening, saving and running the presentations, Selecting the style

for slides, formatting the slides with different fonts, colors, creating charts and tables,

inserting and deleting text, graphics and animations, bulleting and numbering, Hyper-

linking, running the slide show, setting the timing for slide show.

11. Familiarization of PA system with different microphones, loud speakers, mixer etc.

Represent the same in the form of diagrams, write specifications and submit it in the form of a

report.

12. Understand working of various Communication Systems like Television, Satellite

Transmitter & Receiver, Radio Receiver, Mobile Phone. Prepare demo boards/charts of various

communication systems.

PART B: Equipment required for Laboratory

1. Electronic tools

2. Regulated Power supplies

3. Analog/Digital Storage Oscilloscopes

4. Analog/Digital Function Generators

5. Digital Multimeters

6. Decade Résistance Boxes/Rheostats

7. Decade Capacitance Boxes

8. Ammeters (Analog or Digital) and Voltmeters (Analog or Digital)

9. Active & Passive Electronic Components

10. Bread Boards and Connecting Wires

11. CRO Probes etc.

12. Computer hardware.

VEMU INSTITUTE OF TECHNOLOGY::P.KOTHAKOTA

NEAR PAKALA, CHITTOOR-517112 (Approved by AICTE, New Delhi & Affiliated to JNTUA, Anantapuramu)

Department of Electronics &Communication Engineering

LIST OF EXPERIMENTS TO BE CONDUCTED

PART A: Electronic Workshop Practice and List of Experiments

1. Familiarization of commonly used Electronic Workshop Tools

2. Familiarization of Electronic Measuring Instruments

3. Familiarization/Identification of electronic components

4. Testing of electronic components


6. Interpret data sheets of discrete components and IC’s.

7. Introduction to EDA Tools(MULTISIM)

8. Assembling and Testing of simple electronic circuits on breadboards(PCB)

9. Familiarization with Computer Hardware & Operating System


11. Familiarization of PA system with different microphones, loud speakers, mixer etc.

Represent the same in the form of diagrams, write specifications and submit it in the form

of a report.

12. Familiarization of various Communication Systems

.

CONTENTS

S.NO. NAME OF THE EXPERIMENT PAGE NO

PART A: Electronic Workshop Practice

1. Familiarization of commonly used Electronic Workshop Tools 1-11

2. Familiarization of Electronic Measuring Instruments 12-22

3. Familiarization/Identification of electronic components 23-38

4. Testing of electronic components 39-47

5. Study of Cathode Ray Oscilloscope (CRO) 48-59

6. Interpret data sheets of discrete components and IC’s. 60-107

7. Introduction to EDA Tools(MULTISIM) 108-116

8.

Assembling and Testing of simple electronic circuits on

breadboards(PCB) 117-119

9. Familiarization with Computer Hardware & Operating System 120-142

10. Familiarization with Office Tools 143-148

11.

Familiarization of PA system with different microphones, loud speakers,

mixer etc. Represent the same in the form of diagrams, write

specifications and submit it in the form of a report.

149-156

12. Familiarization of various Communication Systems 157-164

PART B: (Advanced Experiments)

1.

2.

DOS & DONTS IN LABORATORY

1. While entering the Laboratory, the students should follow the dress code (Wear shoes, White

Apron & Female students should tie their hair back).

2. The students should bring their observation note book, Lab manual, record note book,

calculator, and necessary stationary items.

3. While sitting in front of the system, check all the cable connections and Switch on the

computer.

4. If a student notices any fluctuations in power supply, immediately the same thing is to be

brought to the notice of technician/lab in charge.

5. At the end of practical class the system should be switch off safely and arrange the chairs

properly.

6. Each program after completion should be written in the observation note book and should be

corrected by the lab in charge on the same day of the practical class.

7. Each experiment should be written in the record note book only after getting signature from

the lab in charge in the observation note book.

8. Record should be submitted in the successive lab session after completion of the experiment.

9. 100% attendance should be maintained for the practical classes.

SCHEME OF EVALUVATION

S No Date Name Of The Experiment

Marks Awarded

Sign. Observ

ation

(10M)

Viva

voce

(10M)

Total

(20M)

PART-A (Electronic Workshop Practice)

1. Familiarization of commonly used Electronic

Workshop Tools

2. Familiarization of Electronic Measuring Instruments

3. Familiarization/Identification of electronic

components

4. Testing of electronic components


6. Interpret data sheets of discrete components and

IC’s.

7. Introduction to EDA Tools(MULTISIM)

8. Assembling and Testing of simple electronic circuits

on breadboards(PCB)

9. Familiarization with Computer Hardware &

Operating System


11.

Familiarization of PA system with different

microphones, loud speakers, mixer etc. Represent

the same in the form of diagrams, write

specifications and submit it in the form of a report.

12. Familiarization of various Communication Systems

PART-B (Advanced Experiments)

1.

2.

Signature of Lab In-charge

ECE Workshop I Year I Sem

VEMU INSTITUTE OF TECHNOLOGY, DEPT OF E.C.E Page 1

Exp.no:1 Date:

Familiarization of commonly used Electronic work shop tools

Aim:To study and identify commonly used Electronic work shop tools

Apparatus required:

1. All Electronicworkshop tools each 1 no.

Theory:

A good workspace set up, to stock with the proper tools and equipment.

1) Breadboards:

In order to temporarily construct a circuit without damaging the components used to build it,

we must have some sort of a platform that will both hold the components in place and

provide the needed electrical connections. In the early days of electronics, most

experimenters were amateur radio operators. They constructed their radio circuits on wooden

breadboards. Although more sophisticated techniques and devices have been developed to

make the assembly and testing of electronic circuits easier, the concept of the breadboard still

remains in assembling components on a temporary platform.

Fig(1.1)(a): A typical Breadboard



Fig(1.1)(b): Breadboard connection details

2) Solder:

Soldering is the process of joining two or more electronic parts together by melting solder

around the connection. Solder is a metal alloy and when it cools it creates a strong electrical

bond between the parts. Even though soldering can create a permanent connection, it can also

be reversed using a desoldering tool as described below.

Fig (1.2)(a): Soldering



Soldering Tools

While working with printed circuit boards and breadboards one needs to use some soldering

tools to connect the circuits with wires and components. For this, there are soldering and de-

soldering tools as follows:

a) Soldering Iron:

A soldering iron is a device for applying heat to melt solder to form an electrical and

physical connection between two surfaces. It is composed of a heated metal tip and an

insulated handle. For electrical projects, wires are usually soldered to PCBs, other wires,

or terminals.

Fig(1.2) (b):Soldering Iron

b) Soldering Station:

The soldering tool stand is used to keep the soldering iron in a place away from

flammable materials. The station also comes with a sponge to clean the tip of the

soldering iron.

Fig(1.2) (c):Soldering Iron Stand



c) De-soldering Tools:

These tools are used to remove the soldered wires and components on printed circuit

boards for repair and troubleshooting usually when there is a fault in the connections.

These include pumps and copper braid wicks. A de-soldering pump draws solder away

with a quick vacuum action.

Fig(1.2) (d):De-soldering Pump

3) Relay:

A relay is an electrically operated switch that opens or closes when power is applied.

Inside a relay is an electromagnet which controls a mechanical switch

Fig (1.3):Relay

Relays are the primary protection as well as switching devices in most of the control

processes or equipments. All the relays respond to one or more electrical quantities like

voltage or current such that they open or close the contacts or circuits. A relay is a



switching device as it works to isolate or change the state of an electric circuit from one

state to another.

Classification or the types of relays depend on the function for which they are used. Some

of the categories include protective, reclosing, regulating, auxiliary and monitoring

relays.

4) Cables:

An electrical cable, or power cable, is used to transmit electrical power. Electrical

cables provide connection and allow power stations, wired computer networks,

televisions, telephones and other electricity-powered devices to work. There are many

types of electrical cables that differ in configuration, size and performance.

Types of cable:

Fig (1.4) (a): Coaxial Cable Fig(1.4)(b):Ribbon Cable

Fig (1.4)(c):Twisted Pair Cable Fig (1.4)(d):Shielded Cable



5) Switch :

Switches can come in many forms such as pushbutton, rocker, momentary and others.

Their basic function is to interrupt electric current by turning a circuit on or off.

The symbol of switch is

fig (1.5)(a): Switch symbolfig(1.5)(b) : Switches

6) Connectors:

An electronic connector is an electro-mechanical device whose purpose is to quickly and

easily disconnect or interrupt a circuit path. Connectors come in a variety of sizes,

shapes, complexities and quality levels. Their function dictates their design and different

features are added to adjust the ease of connection, mating type, durability, insulation

between pins, etc. In addition, because many connectors must perform their job in rugged

conditions, their construction is often adjusted to provide protection from vibrations,

extreme temperatures, dirt, water, contaminants, and more.

fig(1.6): Connectors



7) Fuses:

In electronics and electrical engineering, a fuse is an electrical safety device that operates

to provide overcurrent protection of an electrical circuit. Its essential component is a

metal wire or strip that melts when too much current flows through it, thereby

interrupting the current. It is a sacrificial device; once a fuse has operated it is an open

circuit, and it must be replaced or rewired, depending on type.

fig(1.7) : Symbols for a Fuse

Fuses have been used as essential safety devices from the early days of electrical

engineering.

8) Wire Cutter

Wire cutters are essential for stripping stranded and solid copper wire.

fig(1.8): Wire cutter

Electronics cutters are available in several different sizes and variations.



9) Plier:

Pliers are a hand tool used to hold objects. They are also useful

for bending andcompressing a wide range of materials. Generally, pliers consist of a pair

of metalfirst-class levers joined at a fulcrum positioned closer to one end of the levers,

creating short jaws on one side of the fulcrum, and longer handles on the other side.

fig(1.9): Plier

10) Screwdriver set:

These tools are made of hard steel and are tempered at the tip to loosen or tighten screws

with slotted heads.Screwdrivers can be availed in different shapes and size, mainly including:

Standard/Flat Screw Driver: It is a wedge-shaped driver resembling a negative sign at the tip

and is used for driving screws with a single slot head.

Philips Screw Driver: It has a cross tip resembling a positive (+) sign and used to drive

screws with cross slot heads.

Stubby Screw Driver: It has a short shank or blade and is used in tight spaces where a

standard screw driver can’t be used.



Fig(1.10): Screwdrivers

11) Wire stripper:

A wire stripper is a small, hand-held device used to strip the electrical insulation from

electric wires.



Fig(1.11): Wire stripper

12) Flux:

In metallurgy, a flux (derived from Latin fluxes meaning "flow") is achemical cleaning

agent, flowing agent, or purifying agent. Fluxesmay have more than one function at a

time. They are used in both extractive metallurgy and metal joining.

Fig(1.12): Flux

13) Knife/blade:

It’s one of the essential elements while dealing with electronics as it can cut through most of

the materials. It’s portable, practical, and even has a belt clip for convenient carrying.

Fig(1.13):Knife/blade



Procedure:

1. Take all the tools and place it on the table.

2. Study about each tool thoroughly.

Result: Thus the various Electronic work shop tools are studied.



Exp.no:2 Date:

Familiarization of Electronic measurement instrument

Aim:To study and identify Electronic measurement instruments.

Apparatus required:

1. All electronic measurement instruments each 1 no.

Theory:

With almost every electronic project, one needs to measure certain parameters associated with

the device or circuit like voltage, resistance, current, or some signals, etc. For this purpose, one is

required to have the following tools:

1) Multimeter:

A multimeter is quite important as it measures voltage, current, resistance, and other aspects

of electricity and circuits. Usually, these are small in size, run on batteries, and carry large

digital displays. There is also a knob to select the measurement function and a pair of test

leads for connecting the device to the circuit.

Fig (2.1)(a): Multimeter Fig(2.1)(b):front panel of Multimeter



2. LCR Meter:

LCR meters are used for measuring inductance, capacitance, and resistance involved in

an electronic setup. These are available in two variants- a low-cost version and a high-

cost version. The former one measures the total impedance of a component while the

latter measures all the impedance of the components, equivalent series resistance (ESR)

and the Quality (Q) factor of the component.

Fig (2.2)(a): LCR Meter

Fig(2.2)(b): Front panel of LCR Meter

3. Oscilloscope(CRO):

An oscilloscope displays time-varying signals like voltage waveform patterns on a screen

which help in visualizing the circuit functions. While the basic models



Fig(2.3):Oscilloscope

Functions of front panel controls of CRO

a) Power ON: connects CRO to main supply.

b) AC-DC Control: This controls facilitates to measure DC or AC Quantities.

c) Intensity control: this varies the brightness of the trace.

d) Focus control: It is used to sharp a pattern at the desired brightness.

e) Position: A potentiometer will move horizontal line or trace horizontally.

f) Position: A potentiometer will move vertical line or trace vertically.

g) Volts/Div: It is used to vary the trace amplitude.

h) Time/Div: It is used to vary the trace Timeperiod.

i) Auto /Normal: It is a two way switch, to make normal position of the trace.

j) Astimig: It is used to control the focus of trace.

k) Trig-Level: It is used to control the movement of the trace at lower frequencies.

l) Channel selector: Used to select the channel.

m) INT-Exit mode: In exit position the horizontal deflection system is fed from external

source through the external input. In INT position the horizontal deflection system is fed

from the internally generated sweep waveform.

4. Digital storage oscilloscope (DSO):

A digital storage oscilloscope (often abbreviated DSO) is an oscilloscope which stores

and analyses the signal digitally rather than using analog techniques. It is now the most



common type of oscilloscope in use because of the advanced trigger, storage, display and

measurement features

The input analogue signal is sampled and then converted into a digital record of the

amplitude of the signal at each sample time. The sampling frequency should be not less

than the Nyquist rate to avoid aliasing. These digital values are then turned back into an

analogue signal for display on a cathode ray tube (CRT), or transformed as needed for the

various possible types of output—liquid crystal display, chart recorder, plotter or network

interface

Fig(2.4): Digital storage oscilloscope

6.Function generator :

A function generator is usually a piece of electronic test equipment or softwareused to

generate different types of electrical waveforms over a wide range of frequencies. Some

of the most common waveforms produced by the function generator are the sine wave ,

square wave, triangular wave and sawtooth shapes. These waveforms can be either

repetitive or single-shot

Fig(2.6): Function generator

Functions of front panel controls of Function generator:

1. ON/OFF Switch: this is SPST switch, it may toggle or push button switch used to on or off

the mains supply.

2. Display Screen: Here the frequency input is shown.



3. Coarse and Fine knobs: These knobs are to put different input frequency. Coarse is used to

vary the frequency with large difference. Fine knob is used to vary frequency in decimals.

4. Frequency Range Buttons: These are to change the range of frequency after it’s control we

change frequency with the help of Coarse and Fine Knobs.

5. Duty Cycle knob: It changes the duty cycle of wave.

6. INV button: It invert the signal.

7. Function buttons: To change the type of waveform.

8. ATTN buttons: This control is used to set the voltage level.

9. Sync terminal: This connector sends TTL trigger signals.

10. Output terminal: Through this terminal we get the output from generator.

11. GND: this provides ground reference from output.

7. Ammeters:

An ammeter (from Ampere Meter) is a measuringinstrument used to measure

the current in a circuit. Electric currents are measured in amperes (A), hence the name.

Instruments used to measure smaller currents, in the milliampere or microampere range, are

designated as milliammeters or microammeters.

A Ammeter in a circuit diagram is represented by the letter A in a circle

Fig(2.7)(a): Ammeter function and symbol

Fig(2.7)(b): Ammeter



8. Voltmeters:

A voltmeter is an instrument used for measuring electrical potential difference between

two points in an electric circuit. Analog voltmeters move a pointer across a scale in

proportion to the voltage of the circuit; digital voltmeters give a numerical display of

voltage by use of an analog to digital converter.

A voltmeter in a circuit diagram is represented by the letter V in a circle

Fig(2.8)(a) : voltmeter function and symbol

Fig(2.8)(b): Voltmeter

7. Frequency counter:

A frequency counter is an electronic instrument, or component of one, that is used for

measuring frequency. Frequency counters usually measure the number of cycles of

oscillation, or pulses per second in a periodic electronic signal. Such an instrument is

sometimes referred to as a cymometer.



Fig(2.7): Frequency counter

8. Power supplies:

A power supply is an electrical device that supplies electric power to an electrical load.

The primary function of a power supply is to convert electric current from a source to the

correct voltage, current, and frequency to power the load. As a result, power supplies are

sometimes referred to as electric power converters

Fig(2.8): Power supply

Functions of front panel controls of RPS:

1) On/off switch: The switch is used to supply the external AC power to RPS.

2) Coarse control: It is a rotary switch used to get more than 0.5V variation of voltage.



3) Fine control: it is linear potentiometer used to get very small variations like 0.1V.

4) Over load: An over load indicator blinks when the current control knob is minimum, so

the current is raised until no indicator is given by over load indicator.

5) Current meter: It indicates the current drawn by the circuit.

6) Voltmeter: It indicates the selected voltage appears at the output terminals.

Procedure:

1. Take all the Electronic measurement instrument and place it on the table.

2. Studyeach Electronic measurement instruments thoroughly.

Result: Thus the Electronic measurement instrument are studied



#Exercise About Electronic measuring instruments:

Measurement of AC/DC Voltage & Current using Voltmeter and Ammeter

Aim: To measure DC voltage, DC current, AC voltage, AC current using voltmeter and

Ammeter.

Apparatus Required:

S.no. Name of the component Range Quantity

1 Regulated power supply (0-30)V 1

2 Ammeter (0-20)mA 1

3 Voltmeter (0-20)V 1

4 Function Generator (20-20K)Hz 1

5 Bread board - 1

6 Resistor 1K ohm 1

7 Probes - 1

8 Connecting wires - As per required

Circuit diagram for measurement of dc voltage and current:

Figure (A)

Circuit diagram for measurement of ac voltage and current:

Figure (B)



Procedure:

1. Connect the circuit as shown in figure (A).

2. Apply different voltages from regulated power supply.

3. Tabulate the ammeter and voltmeter readings.

4. Plot a graph between voltage and current by taking voltage on x-axis and current on y-

axis.

5. Now connect the circuit as shown in figure (B).

6. Apply different voltage from AFO.

7. Repeat 3&4 steps again.

Model Graph:

Tabular column for measurement of dc voltage and current:

S.no Voltmeter reading(Volts) Ammeter reading(mA) R=V/I(ohms)



Tabular column for measurement of ac voltage and current:

S.no Voltmeter reading(Volts) Ammeter reading(mA) R=V/I(ohms)

Result:



Exp.no:3 Date:

Identification of Electronic components

Aim:To study functionality of Electronic components and Draw the symbols for the various

electronic circuit symbols.

Apparatus required:

1. All Electronic components each 1 no.

Theory:

An electronic circuit comprises of various types of components, which are classified into

two types: active components like transistors, diodes, IC’s; and passive components like

capacitors, resistors, inductors, etc.

In designing of an electronic circuit following are taken into consideration:

• Basic electronic components: capacitors, resistors, diodes, transistors, etc.

• Power sources: Signal generators and DC power supplies.

• Measurement and analysis instruments: Cathode Ray Oscilloscope (CRO), multimeters, etc.

3.1)Passive Electronic Components

These components can store or maintains energy either in the form of current or voltage. Some

of these components are discussed below.

1. Resistor:

Resistors are the most commonly used components in electronic circuits and devices. The

main purpose of a resistor is to maintain specified values of voltage and current in an

electronic circuit. A Resistor works on the principle of Ohm’s law and the law states that

the voltage across the terminals of a resistor is directly proportional to the current flowing

through it.

V = I R

Where V is the potential difference between two points which include a resistance R. I is

the current flowing through the resistance.

The unit of resistance is Ohm and the symbol of resistor is as follows:



Fig(3..11)(a): Symbol of resistor

Color coding:

Tab (3.1.1): Color coding

Tab (3.1.2): Color coding and its values in range



The colors brown, red, green, blue, and violet are used as tolerance codes on 5-band

resistors only. All 5-band resistors use a colored tolerance band. The blank (20%) “band”

is only used with the “4-band” code (3 colored bands + a blank “band”).

Fig (3.1)(b): resistor with 4-band and 5-band code

Example #1

A resistor colored Yellow-Violet-Orange-Gold would be 47 kΩ with a tolerance of +/- 5%.



Example #2

A resistor colored Green-Red-Gold-Silver would be 5.2 Ω with a tolerance of +/- 10%.

Example #3

A resistor colored White-Violet-Black would be 97 Ω with a tolerance of +/- 20%. When you

see only three color bands on a resistor, you know that it is actually a 4-band code with a

blank (20%) tolerance band.

Resistors are further classified based on the following specifications such as the power

rating, type of material used and resistance value. This resistor types are used for different

applications.

a) Fixed resistors:

This type of resistor is used to set the right conditions in an electronic circuit. The values of

resistance in fixed resistors are determined during the design phase of the circuit, based on

this there is no need to adjust the circuit.



b) Variable resistors:

A device that is used to change the resistance according to our requirements in an electronic

circuit is known as a variable resistor. These resistors comprise of a fixed resistor element

and a slider which taps on to the resistor element. Variable resistors are commonly used as a

three terminal device for calibration of the device.

2) Capacitors:

A capacitor made from two conductive plates with an insulator between them and it stores

electrical energy in the form of an electric field. A capacitor blocks the DC signals and

allows the AC signals and also used with a resistor in a timing circuit.

The stored charge is Q=CV

Where

C is the capacitance of a capacitor and V is the applied voltage.

Fig(3.1.2):Capacitor



These capacitors are different types like film, ceramic, electrolytic and variable

capacitors. For finding its value number and color coding methods are used and it also

possible to find the capacitance value with LCR meters.

Types of Capacitors:

1. Film Capacitors

2. Ceramic Capacitors

3. Electrolytic Capacitors

4. Variable Capacitors

Each capacitor has its own capacitance which is expressed as the Charge in the capacitor divided

by the Voltage. Thus Q/V. When you use a capacitor in a circuit, some important parameters

should be considered. First is its Value, The value is printed on the body of most of the

capacitors in uF or as EIA code. In Color coded capacitors, the values are represented as color

bands and by using a capacitor color code chart; it is easy to identify the capacitor. Below is the

Color chart to identify a color coded capacitor.



Capacitor Colour Code Table:

Table: (3.1.2): Capacitor Colour Code

Example:

For example, if the colors on a 4 color band capacitor is in this order: yellow, brown, red and

green. The values of color band will be likes this: Yellow = 4, Brown = 1, Red = 100 or 102 and

Green = 5%.

3) Inductors:

An inductor is also referred as AC resistor which stores electrical energy in the form of

magnetic energy. It resists the changes in the current and the standard unit of inductance is

Henry. Capability of producing magnetic lines is referred as inductance.

The inductance of the inductor is given as L= (µ.K.N2.S)/I.



Where,

L is inductance,

µ is Magnetic permeability,

K is magnetic coefficient,

S is the Cross section area of the coil,

N is the Number of turns of the coils,

And I is the Length of the coil in axial direction.

Fig(3.1.3): Inductor symbol

3.2) Active Electronic Components:

These components rely on a source of energy and are able to control the electron flow through

them. Some of these components are semiconductors like diodes, transistors, integrated circuits,

various displays like LCD, LED, CRTs and power sources like batteries, PV cells AND OTHER

AC AND DC SUPPLY SOURCES.



4) DIODES:

A diode is a device that allows current to flow in one direction and usually made with

semiconductor material. A Diode is an electronic component with two terminals that are anode

and cathode. It allows electron current flow from cathode to anode but it blocks another

direction. The diode will have low resistance in one direction and high resistance in another

direction.. These are mostly used in converting circuits like AC to DC circuits.

A Diode is an electronic component with two terminals that are anode and cathode. It allows

electron current flow from cathode to anode but it blocks another direction. The diode will have

low resistance in one direction and high resistance in another direction

These are of different types like PN diodes, Zener diodes, LEDs, photo diodes, etc.

Fig(3.2.1) (a): Symbol of diode

Different Types of Diodes

The diodes are classified into various types that are discussed below along with their symbols:



Fig(3.2.1) (b) : Symbol of various diodes

:

Fig (3.2.1) (c): types of diodes

Diode: A diode allows the current flow in one direction.

Light Emitting Diode: It will emit the light when the electric current flows through it.

Zener Diode: It will allow a constant electric current after the breakdown voltage.

Photo Diode: Photodiode will convert light into respective current or voltage.



Tunnel Diode: Tunnel diode is used for very high-speed operations.

Schottky Diode: Schottky diode is for forwarding low voltage drop.

5) TRANSISTORS:

A transistor is a three terminal semiconductor device. Mostly it is used as switching device and

also as an amplifier. This switching device can be a voltage or current controlled.By controlling

the voltage applied to the one terminal controls the current flow through the other two terminals.

Transistors are of two types, namely bipolar junction transistor (BJT) and field effect transistors

(FET). And further these can be PNP and NPN transistors.

Fig (3.2.2) (a) :symbol of transistors

Types of transistors along with symbols as shown below:

NPN transistor: A P-type doped semiconductor material is placed in between two N-type

semiconductor materials. The terminals are the emitter, base, and collector.

PNP transistor: A N-type doped semiconductor material is placed in between two P-type

semiconductor materials. The terminals are an emitter, base, and collector.

Phototransistor: It is similar to bipolar transistors, but it converts light to current.

Field Effect Transistor: FET controls the conductivity with the help of an electric field.



Fig(3.2.2) (b) : Symbol of various transistors

N-channel JFET: The Junction Field Effect Transistors are simple of FET for switching.

P-channel JFET: P-type semiconductor is placed in between N-type junctions.

Enhancement MOSFET: Similar to DMOSFET but an absence of conducting channel.

Depletion MOSFET: The current flows from source to drain terminal.

6) INTEGRATED CIRCUITS:

An Integrated circuit is a special component which is fabricated with thousands of transistors,

resistors, diodes and other electronic components on a tiny silicon chip. These are the building

blocks of current electronic devices like cell phones, computers, etc. These can be analog or

digital integrated circuits. Mostly used ICs in electronic circuits are Op-amps, timers,



comparators, switches ICs and so on. These can be classified as linear and nonlinear ICs

depending on its application.

Fig (3.2.3) :Integrated Circuits

Types of Integrated Circuits:

Like electronic circuit, ICs can also be categorized as digital IC and analog ICbased on their

applications.

Analog IC

In this type of ICs, the input and output both signals are continuous. The output signal level

depends upon the input signal level and the output signal level is a linear function of input signal

level. Linear ICs or analog ICs are most commonly used as audio frequency amplifier and radio

frequency amplifier. Op amps, voltage regulators, comparators and timers are also well-known

examples of linear ICs or analog ICs.

Digital IC

The logic Gates, such as AND gate, OR gate, NAND gate, XOR gate, flip flops, counters;

microprocessors are some well-known examples of digital ICs. These ICs operate with binary

data such as either 0 or 1. Normally in digital circuit, 0 indicates 0 V and one indicate +5 V.

List of various electronic components:

S.no Name of the component Symbol of the component

1 Resistor 2 Variable resistor

3 Photo resistor

4 Capacitor



5 Variable capacitor

6 Inductor 7 Variable inductor

8 Transformer

9 Center tap transformer

10 Diode

11 Zener diode

12 Photo diode

13 LED

14 NPN transistor

15 PNP transistor

16 Photo transistor

17 SCR

18 Armature

19 Push button switch

20 Relay

21 Circuit breaker

22 DC source



23 Amplifier

24 AC source

25 Analog ground

26 Antenna

27 Loud speaker

28 Crystal

29 Earth

30 Fuse

31 Potentiometer

32 Traic

33 Tunnel diode

34 FET

35 UJT

36 Diac



Procedure:

1. Take all the components and place it on the table.

2. Study each component thoroughly and symbols for various electronic components.

Result:Thus the various electronic components were studied.



Exp.no:4 Date:

Testing of electronic components

a)Testing of Resistance

Aim:To measure resistance of a resistorby using DMM.

Apparatus required:

1. Digital multimeter

2. Test leads

3. Sample Resistors

Procedure:

1. Switch on the multimeter.

2. Connect the black test leads to the common terminal and red test leads to V() terminal.

3. Set the Function switch to Ohms range.

4. Connect the test leads across the resistance under measurement.

5. Resistance value is displayed on LCD.

6. Use the color code and find the value resistance for the resistors.

7. Compare the measured value with the value found by color code.

Circuit diagram:



Tabular column for measurement of resistance:

S.no Theoritical value Measured value Error

Calculations:

Results:Thus measured the resistance of resistors by using DMM.

.



b)Testing of Capacitance

Aim:To measure capacitance of capacitors by using DMM.

Apparatus required:

1. Digital multimeter

2. Test lead

3. Sample Capacitors

Procedure:

1. Make sure the capacitor is discharged.

2. In the Digital Multimeter, set the knob to capacitance settings.

3. Connect the multimeter probes to the terminals of the capacitor. In case of a polarized

capacitor, connect the red probe with thepositive terminal of the capacitor (generally, the

longer lead) and the black probe to the negative terminal. In case of non – polarized

capacitor, connect it either way as they do not have polarity.

4. Now, check the readings on the Digital Multimeter. If the multimeter readings are closer to

the actual values (mentioned on the capacitor), then the capacitor can be considered as a

good capacitor.

5. If the difference between the actual value and the measured reading is significantly large

(or sometimes zero), then you should replace the capacitor as it is a dead one.

6. Use the color code and find the value resistance for the resistors.

7. Compare the measured value with the value found by color code.

Circuit diagram:



Tabular column for measurement of capacitance:

S.no Theoritical value Measured value Error

Calculations:

Results:Thus measured the resistance of resistors by using DMM.



c)Testing of Diode

Aim:To identify the terminals and test the given diode by using DMM.

Apparatus required:

1. Digital Multimeter

2. Sample diodes

Procedure:

• Identify the terminals anode and cathode of the diode.

• Keep the digital multimeter (DMM) in diode checking mode by rotating the central knob

to the place where the diode symbol is indicated. In this mode multimeter is capable to

supply a current of 2mA approximately between the test leads.

• Connect the red probe to the anode and black probe to the cathode. This means diode is

forward-biased.

• Observe the reading on meter display. If the displayed voltage value is in between 0.6 to

0.7 (since it is silicon diode) then the diode is healthy and perfect. For germanium diodes

this value is in between 0.25 to 0.3.

• Now reverse the terminals of the meter that means connect the red probe to cathode and

black to anode. This is the reverse biased condition of the diode where no current flows

through it. Hence the meter should read OL (which is equivalent to open circuit) if the

diode is healthy.

Circuit diagram:



Tabular column:

S.no. Connecting Com lead to cathode

and V lead to anode measure

resistance

Connecting Com lead to anode and

V lead to cathode measure

resistance

Observations:

1. Number of the diode :

2. Type of material used :

3. Break down voltage :

4. Diode working condition :

Calculations:

Results:Thus identified the terminals and tested the given diode by using DMM.



d)Testing of Transistor

Aim:To identify the terminals and test the given Transistor by using DMM.

Apparatus required:


2. Sample diodes

Procedure:

1) Insert the probesinto the multimeter. The black probe goes into the common terminal and

the red probe goes into the terminal marked for testing diodes.

2) Turn the selector knob to the diode test function.

3) Replace the probe tips with alligator clamps.

4) Determine which leads are the base, emitter and collector.

5) Clamp the black probe to the base of the transistor.Touch the red probe to the

emitter. Read the display on the multimeter and note whether the resistance is high or

low.

6) Move the red probe to the collector. The display should give the same reading as when

you touched the probe to the emitter.

7) Remove the black probe and clamp the red probe to the base.Touch the black probe to the

emitter and collector. Compare the reading on the multimeter's display to the readings

you got previously.

8) Touch the black probe to the emitter and collector. Compare the reading on the

multimeter's display to the readings you got previously.

Touch the black probe to the emitter and collector.Compare the reading on the multimeter's

display to the readings you got previously.

9) If the previous readings were both high and the current readings are both low, the

transistor is good.

10) If the previous readings were both low and the current readings are both high, the

transistor is good.



11) If both readings you receive with the red probe are not the same, both readings with the

black probe are not the same, or the readings don't change when switching probes, the

transistor is bad.

Circuit diagram:

Tabular column:

Transistor terminals(black

probe)

Transistor terminals(black

probe)

Resistor value(high or low)

Base Emitter

Base Collector

Emitter Collector

Emitter Base

collector Base

collector Emitter

Calculations:

Results:Thus identified the terminals and tested the given diode by using DMM.



e)Testing of ICs

Aim:To identify the terminals and test the given ICs by using DMM.

Apparatus required:


4. Sample ICs

Procedure:

• Set your multimeter to the continuity mode.

• Connect all of the pins altogether from one of the side in IC to the multimeter cable.

• Take the terminal-cable from multimeter and connect it one by one to each of the pins of

another side separately.

• If the beep sound occurs of there is a continuity in more than 50% of the combinations

then there is a good chance of the IC to be shorted from inside

• In this Method you have to test an IC that weather the package is damaged or is blown.

• Take the observation of the IC from each of the sides possible, if you see even a little

crack, burned mark or its broken from either side then the IC is surely to be Damaged or

Leaked..

Circuit diagram:

Results: Thus identified the terminals and tested the given diode by using DMM.



Exp.no:5 Date:

Study of Cathode rayOscilloscope(CRO)

Study of CRO & Measurement of Voltage Amplitude & Frequency

Aim: 1. Study of CRO and to find the Amplitude and Frequency using CRO.

2. To measure the Unknown Frequency & Phase difference using CRO.

Components and Equipments Required: 1. Cathode-ray oscilloscope,

2. Function Generator (2),

3. Decade Resistance Box (DRB),

4. Capacitor,

5. CRO Probes and

6. Bread Board.

Theory: An outline explanation of how an oscilloscope works can be given using the block diagram

shown below.

Fig. 1: Cathode Ray Oscilloscope



Like a television screen, the screen of an oscilloscope consists of a Cathode Ray Tube.

Although the size and shape are different, the operating principle is the same. Inside the tube is a

vacuum. The electron beam emitted by the heated cathode at the rear end of the tube is

accelerated and focused by one or more anodes, and strikes the front of the tube, producing a

bright spot on the phosphorescent screen.

The electron beam is bent, or deflected, by voltages applied to two sets of plates fixed in

the tube. The horizontal deflection plates or X-plates produce side to side movement. As you can

see, they are linked to a system block called the time base. This produces a saw tooth waveform.

During the rising phase of the saw tooth, the spot is driven at a uniform rate from left to right

across the front of the screen. During the falling phase, the electron beam returns rapidly from

right ot left, but the spot is 'blanked out' so that nothing appears on the screen. In this way, the

time base generates the X-axis of the V/t graph.

The slope of the rising phase varies with the frequency of the saw tooth and can be

adjusted, using the TIME/DIV control, to change the scale of the X-axis. Dividing the

oscilloscope screen into squares allows the horizontal scale to be expressed in seconds,

milliseconds or microseconds per division (s/DIV, ms/DIV, μs/DIV). Alternatively, if the

squares are 1 cm apart, the scale may be given as s/cm, ms/cm or μs/cm.

The signal to be displayed is connected to the input. The AC/DC switch is usually kept

in the DC position (switch closed) so that there is a direct connection to the Y-amplifier. In the

AC position (switch open) a capacitor is placed in the signal path. The capacitor blocks DC

signals but allows AC signals to pass.

The Y-amplifier is linked in turn to a pair of Y-plates so that it provides the Y-axis of the

theV/t graph. The overall gain of the Y-amplifier can be adjusted, using the VOLTS/DIV control,

so that the resulting display is neither too small nor too large, but fits the screen and can be seen

clearly. The vertical scale is usually given in V/DIV or mV/DIV.

The trigger circuit is used to delay the time base waveform so that the same section of the input

signal is displayed on the screen each time the spot moves across. The effect of this is to give a

stable picture on the oscilloscope screen, making it easier to measure and interpret the signal.

Changing the scales of the X-axis and Y-axis allows many different signals to be

displayed. Sometimes, it is also useful to be able to change the positions of the axes. This is

possible using the X-POS and Y-POS controls. For example, with no signal applied, the normal



trace is a straight line across the centre of the screen. Adjusting Y-POS allows the zero level on

the Y-axis to be changed, moving the whole trace up or down on the screen to give an effective

display of signals like pulse waveforms which do not alternate between positive and negative

values.

Fig. 2: Front View of Oscilloscope

Screen: Usually displays a V/t graph, with voltage V on the vertical axis and time t on the

horizontal axis. The scales of both axes can be changed to display a huge variety of signals.

Fig(3)

On/Off Switch: Pushed in to switch the oscilloscope on. The green LED illuminates.

X-Y Control: Normally in the OUT position. When the X-Y button is pressed IN, the

oscilloscope does not display a V/t graph. Instead, the vertical axis is controlled by the input

signal to CH II. This allows the oscilloscope to be used to display a V/V voltage/voltage graph.

The X-Y control is used when you want to display component characteristic curves, or Lissajous

figures. (Links to these topics will be added later.)



TV-Separation: Oscilloscopes are often used to investigate waveforms inside television

systems. This control allows the display to be synchronized with the television system so that the

signals from different points can be compared.

TimeDiv: Allows the horizontal scale of the V/t graph to be changed.

With more experience of using the oscilloscope, you will develop a clear understanding of the

functions of the important trigger controls and be able to use them effectively.

Intensity and Focus: Adjusting the INTENSITY control changes the brightness of the

oscilloscope display. The FOCUS should be set to produce a bright clear trace.

If required, TR can be adjusted using a small screwdriver so that the oscilloscope trace is exactly

horizontal when no signal is connected.

X-POS: Allows the whole V/t graph to be moved from side to side on the oscilloscope screen.

This is useful when you want to use the grid in front of the screen to make measurements, for

example, to measure the period of a waveform.

Y-POS I and Y-POS II: These controls allow the corresponding trace to be moved up or down,

changing the position representing 0 V on the oscilloscope screen.

To investigate an alternating signal, you adjust Y-POS so that the 0 V level is close to the centre

of the screen. For a pulse waveform, it is more useful to have 0 V close to the bottom of the

screen. Y-POS I and Y-POS II allow the 0 V levels of the two traces to be adjusted

independently.

Invert: When the INVERT button is pressed IN, the corresponding signal is turned upside down,

or inverted, on the oscilloscope screen. This feature is sometimes useful when comparing signals.

CH I And CH II Inputs: Signals are connected to the BNC input sockets using BNC plugs.



Volts / Div: Adjust the vertical scale of the V/t graph. The vertical scales for CH I and CH II can

be adjusted independently.

DC/AC/GND Slide Switches: In the DC position, the signal input is connected directly to the Y-

amplifier of the corresponding channel, CH I or CH II. In the AC position, a capacitor is

connected into the signal pathway so that DC voltages are blocked and only changing AC signals

are displayed.

In the GND position, the input of the Y-amplifier is connected to 0 V. This allows you to check

the position of 0 V on the oscilloscope screen. The DC position of these switches is correct for

most signals.

Trace Selection Switches: The settings of these switches control which traces appear on the

oscilloscope screen.

Measurement of Amplitude & Frequency:

Fig(6):



Model waveforms:

Fig(7)

waveforms: Fig. 7: Sinusoidal waveform



A) Measurement of Amplitude:

Procedure: 1. Make the connections as per the diagram shown above.

2. Put the CRO on a single channel mode and bring the CRO into operation by adjusting the

trace of the beam to a normal brightness and into a thin line.

3. Now apply the sinusoidal wave of different amplitudes by using the LEVEL and COARSE

buttons of the function generator.

4. Note on the vertical scale the peak to peak amplitude (Vpp).

Observations:

B) Measurement of Frequency:

Procedure: 1. Make the connections as per the diagram shown above.

2. Put the CRO on a single channel mode and bring the CRO into operation by adjusting the

trace of the beam to a normal brightness and into a thin line.

3. Now apply the sinusoidal wave of different frequencies by using the LEVEL and COARSE

buttons of the function generator.

4. Note down the horizontal scale period (T) in second by observing difference between the two

successive peaks of the waveform.



Observations:

C) Measurement of Unknown Frequency:

Fig. 8: Measurement of Unknown Frequency



Procedure: 1. Connect the unknown frequency to the vertical (Y) deflection plates (CH -1) and the known

frequency to the horizontal (X) deflection plates (Ch-2) from two function generators as shown

in the figure.

2. Press X- Y mode button on the CRO and obtain the LISSAJOUS PATTERN. The lissajous

pattern is obtained when two sinusoidal signals of different frequencies are applied to the X and

Y deflection plates of the CRO. If the two frequencies are equal, we get a circle or ellipse.

3. Note down Nx (Number of touching points on X- axis), Ny( Number of touching points on Y

– axis), Fx ( Frequency of known signal).

4. If the LISSAJOUS pattern obtained is not clear to note the readings, Vary the known

frequency such that a clear lissajous pattern is obtained.

5. The unknown frequency Fy is given by Fy = (Nx * Fx) / (Ny)

Observations:



D) Measurement of Phase Difference:

Fig. 9: Measurement of Phase Difference



Procedure:

1. Connect the RC phase shift network as shown above in the circuit diagram.

2. Obtain a sinusoidal signal of 5V (Pk- Pk) at 1 KHz from the function generator.

3. Connect the signal from the function generator to the input of the RC phase shift network and

the same signal to the CH-1 of the CRO.

4. Connect the output of the Phase shift network to the CH-2 of the CRO.

5. Press X- Y mode button.

6. The pattern obtained on the screen will be an ellipse.

7. The phase difference between the two signals (θ) is given by θ = sin-1(B/A).

8. By varying the different values of the resistances from DRB, frequencies, note the values of B

and A and hence find θ.

Observations:



Results: 1. Working of CRO is studied. Amplitude and Frequency a signal is found using CRO.

2. Unknown Frequency & Phase difference are measured using CRO.



Exp.no:6 Date:

Study of Datasheets of discrete components and IC’s

Aim:To write important specifications of/ratings of components and ICs and also submit it in

the form of a report.

Apparatus required:

1. All electronic components and ICs.

Theory:

a) Resistor:

1k ohm 1/4W 5% Carbon Film Resistor

Features:

1. Automatically insertable

2. High quality performance

3. Non - Flame type available

4. Cost effective and commonly used

5. Too low or too high can be supplied on a case to case basis

6. For 1k ohm resistor the fearures:

• High Reliability 1k ohm Resistor

• ±5% Tolerance Carbon Film Type

• Excellent Heat and Humidity Withstand Performance

• Long Life

• RoHS Compliant

• Note: Picture for General Indication, Not Actual Color Code



b) Capacitor:

CERAMIC CAPACITORS

Ceramic Disc Capacitors

• With tolerance of ±20%

• Dielectric Strength of 250% for less

than 1 sec

• High quality and stable operating

voltage

• Also available in prepacked quantities

of 100 and 1,000

HIGH VOLTAGE CERAMIC CAPACITORS

High Voltage Ceramic Disc Capacitors


• Operating Temperature: -10°C to +85°C

• Low Leakage Current

• Dielectric Withstand of 2.5 times rated voltage

for less than 1 sec.

• Available in rolls of 100 or 1,000 at special

prices.

MONOLITHIC CAPACITORS

Monolithic Multilayer Capacitors


• Temperature range -10°C to +85°C

• Miniature Size

• Available in 1,000 pieces ammo style

packing

https://www.futurlec.com/CapCerHigh.shtml

https://www.futurlec.com/CapCerMono.shtml

https://www.futurlec.com/CapCer.shtml

https://www.futurlec.com/CapCerHigh.shtml

https://www.futurlec.com/CapCerMono.shtml



1pF 50V Ceramic Capacitor

Features:

• Standard Type - 1pF 50V

• Long Life

• Low CostA

• Easy Mounting

• RoHS Compliant

c) Diode:

Mechanical Characteristics

• Case: Epoxy, Molded

• Weight: 0.4 gram (approximately)

• Finish: All External Surfaces Corrosion Resistant and Terminal Leads are

Readily Solderable

• Lead and Mounting Surface Temperature for Soldering Purposes:

• 220°C Max. for 10 Seconds, 1/16, from case

• Available Tape and Reeled, 5000 per reel, by adding a “RL” suffix to the part number

• Polarity: Cathode Indicated by Polarity Band

• Marking: 1N4001, 1N4002, 1N4003, 1N4004, 1N4005, 1N4006, 1N4007

Symbol:

1N4007



PACKAGE DIMENSIONS:



d) Zener Diode:

ELECTRICAL CHARACTERISTICS:



RATINGS AND CHARACTERISTIC CURVES 1N5230:

e) Transistor:

1)NPN Transistor:(BC547)

Symbol:



PACKAGE DIMENSIONS:

2)PNP Transistor:(BC556)

• Symbol:



PACKAGE DIMENSIONS:

f) NPN general purpose transistors BC107:



PACKAGE OUTLINE:



g)MOSFET(BS170):

BS170



Characteristic curve:



• Integrated circuits: (ICs)

1)NAND(7400):



Physical Dimensions:



2) NOR(7402):



3)AND(7408):



3)OR(7432):



4)EX-OR(7486):



i) Operational Amplifier(741 op-amp):



j)TIMER(555):



j)NEGATIVE VOLTAGE REGULATORS

L7900 SERIES



k) VOLTAGE REGULATORS

L7800 SERIES



Procedure:

1 Switch on the multimeter.

2 Connect the black test leads to the common terminal and red test leads to V() terminal.

3 Set the Function switch to Ohms range.

4 Connect the test leads across the resistance under measurement.

5 Resistance value is displayed on LCD.

6 Use the color code and find the value resistance for the resistors.

7 Compare the measured value with the value found by color code.

Circuit diagram:



Results: Important specifications of/ratings of components and ICs along datasheets were

mentioned and also submitted it in the form of a report.



Exp.no:7 Date:

Introduction to EDA Tools

Aim: To Learning of basic functions of creating a new project, getting and placing parts,

connecting placed parts, simulating the schematic, plotting and analyzing the results using

MULTISIM/PSPICE/TINA Schematic capture tool.

Apparatus required:

PC, Multisim software tool

Theory:

MULTISIM:

The most popular simulator is SPICE (Simulation Program with Integrated Circuit Emphasis)

designed at the University of California at Berkeley. This simulator is so powerful that

commercial simulators are based on it. Of the many simulators available, Multisim has emerged

as the best for circuit simulation. Multisim is a SPICE-based simulator, produced by National

Instruments Inc. in Austin, TX, with a schematic-capture interface that allows easy circuit

topology input and specification of simulation data.

The first circuit we analyze in Multisim is shown in Fig. 2.1. It is a resistive circuit with an

independent DC voltage source.

Figure 2.1: Resistive circuit with an independent DC voltage source.

This circuit has three resistors and an independent voltage source. When we open Multisim, it

shows a blank schematic page where we can draw our schematic circuit, several windows, and

some toolbars, as shown in Fig. 2.2. Some of the icons in the toolbars are conventional ones such

as Open file, Copy, Save, etc. The windows shown are the larger window to draw the circuit

called the Design Toolbox window, and the Results/Nets/Components window. One of the

toolbars is the Components toolbar and it contains links to some of the different components

available to draw our circuits. Table 2.1 gives a short description of the icons available in this

toolbar.



Figure 2.2: Multisim window.

Note that a schematic page with a default name Design1 is open. This opens the window

Shown in Fig. 2.3. There we can begin to draw our circuit. We first place the DC voltage source.

We do this by selecting the Sources icon (the left-most icon) in the Components Toolbar. There

we select DC_POWER→POWER_SOURCES→DC_POWER and press OK. The DC voltage

source is shown in the schematic page attached to the mouse. It can be moved along the

schematic page by moving the mouse. It is placed in the desired position by left clicking the

mouse. The same window is open again to select a new component. If we wish to place another

DC voltage source we select it and press the OK button. Now we place the resistors, otherwise

we press the Close button.

Figure 2.3: Selecting the DC_POWER source.



We click on the Basic icon in the Component toolbar. The window in Fig. 2.4 is open. There are

two possibilities to choose a resistor. The first one is in the RATED VIRTUAL set of

components and the second one is the RESISTOR set. The VIRTUAL set has components that

can have any value, for example, we can place a resistor with a value of 23.457 ohms. In the

resistor set we can only place resistors with predetermined commercial values. In our example

we can use both sets. For R1 we use the RATED VIRTUAL set and for R2 and R3 we use the

resistor set. Thus, after placing R1 we are returned to the same window to select the following

component and there we press the Close button.

Figure 2.4: Selecting resistor R1.

For R2 and R3 we select the RESISTOR set and place them in the schematic page (Fig. 2.5 (a)).

Figure 2.5: (a) Schematic page with components



To place R2 in a vertical position we select it with the mouse and press Control-R. We repeat

with R3. Finally, we have to place a ground symbol, which it is available from the sources icon.

We note there are two ground symbols: GROUND and DGND. The last one is used in digital

circuit simulation. We choose GROUND and place it on the schematic page.

The schematic page with the components is shown in Figure 2.5: (b)

Figure 2.5: (b) With resistors R2 and R3 after rotation.

To wire up the components we place the pointer in the upper end of the DC power source, we

click the left mouse button to start the wire, then drag the pointer to the left end of R1 and left

click again. A wire connecting the voltage source and resistor R1 has been created. Now, connect

the remaining elements. The complete circuit is shown in Fig. 2.6.

Figure 2.6: Resistive circuit.



In this figure, node numbers are shown next to each node. Node numbers or names are displayed

if we select in the main menu Edit Properties which opens the dialog window shown in Fig. 2.7

and in the Net names box we select Show all, as shown there.

Figure 2.7: Dialog window for displaying node numbers on the schematic diagram.

Figure 2.8: Window to change the value of resistor R1.



Figure 2.9: Final circuit in Multisim.

Figure 2.10: Choosing the DC Operating Point Analysis



Figure 2.11: Window to choose the variables to display.

Figure 2.12: Variables to be displayed after the analysis.



press the Add button. The variables selected are now displayed in the right window (see Fig.

2.12). Now press the Simulate button and after the analysis is run, Multisim displays the values

of the variables selected before I(v1) and V(2) shown in Fig. 2.13. There we see that the current

through the voltage source is -4 mA, indicating that the current is leaving the positive terminal

in. in the voltage source, and that the voltage at node 2 is 2 volts.

Figure 2.13: Values of the variables chosen in Fig. 2.12.

Figure 2.14: Window to select a voltmeter in the indicators window.



Procedure:

1. Observe the circuit behavior before the actual manufacturing

2. Use ideal components to isolate design and circuit limitations

3. Make measurements that are hard to make in the real circuit because they might damage the

circuit

4. Perform repeated simulations with parametric values for a component

5. Observe temperature dependence of the circuit behavior

6. Observe circuit behavior under parasitic elements due to real components.

7. These are only a few of the many advantages of using circuit simulation.

Result:



Exp.no:8 Date:

Assembling and Testing of simple electronic circuits on breadboards

Aim: To identifying the components and its location on the PCB, Soldering of the components,

testing the assembled circuit for correct functionality.

Apparatus required:

1. All Electronic workshop tools each 1 no.

Theory:

A breadboard is a rectangular plastic board with a bunch of tiny holes in it. These holes let you

easily insert electronic components to prototype (meaning to build and test an early version of)

an electronic circuit, like this one with a battery, switch, resistor, and an LED (light-emitting

diode).

Fig (8.1): assembling electronic components on breadboard

The connections are not permanent, so it is easy to remove a component if you make a mistake,

or just start over and do a new project. This makes breadboards great for beginners who are new

to electronics.

The manual artwork PCB design is the method used by most manufacturing of PCB with this

method extremely accurate, high density PCB can be constructed. This artwork is then

photographed to produce a negative which can be used with sensitized printed circuit. The

simplest PCBs are single sided boards (one copper layer). However, the copper traces can also be

installed on both sides of the board, creating a double sided PCB. They become more and more

complex as additional layers are added to the original design. These new layers have their own

copper trace formations. The copper connections cannot cross one another without the path of

the electrical charge being compromised, so multi layered PCBs become necessary for advanced

http://www.pcbtrain.co.uk/blog/single-layer-vs-multi-layer-pcbs



electronics. However, in the single sided boards one side is reserved for the copper trace and the

other side houses the components.

On top of the copper layer sits the solder mask and the silkscreen. The solder mask is what

makes the PCB its recognisable green colour. This has the function of insulating the copper from

any metal parts that might accidently come into contact with it. However, parts of the metal will

remain exposed so that they can be soldered to. The silkscreen sits on top of the solder mask

again. This has letters and numbers drawn on it which make the assembly of the PCB easier for

the engineer.

Fig (8.2): PCB

If the copper traces behave like the skeleton of the PCB, acting as its basic structure – then the

components are the vital organs. Each one has a different function. They give the circuit the

unique qualities that make it fit for its intended purpose. Depending on the device or electronic

item a PCB is designed for, different components will be needed for different circuits. These

components can consist of a wide range of electronic parts. Some common PCB components

include:

Battery: provides the voltage to the circuit.

Resistors: control the electric current as it passes through them. They’re color coded to

determine their value.

LEDs: light emitting diode. Lights up when current flows through it, and will only allow current

to flow in one direction.

Transistor: amplifies charge.

Capacitates : these are components which can harbor electrical charge.

Inductor: stores charge and stops and change in current.

https://www.pcbtrain.co.uk/blog/12-cool-facts-about-pcbs-that-you-probably-didnt-know

http://www.pcbtrain.co.uk/blog/wp-content/uploads/2015/08/shutterstock_164657354forweb.jpg



Diode: allows current to pass in one direction only, blocking the other.

Switches: can either allow current or block depending if they are closed or open.

PCB Assembly

Fig (8.3): PCB Assembling

These components can be attached to the board in various ways. In general, an engineer will

choose to use either the surface mount method or the through-hole method to attach the

components. Following a schematic pattern and using the numbers on the silkscreen, the

engineer uses solder to attach the components to the board. The engineer must be very careful

when soldering. As solder is a metal that an engineer melts so that they can manipulate it. Any

stray blobs that are out of place and touch other metal components could cause the circuit to

short. This can be dangerous, causing fires or even small explosions. When the components are

installed correctly, the PCB is ready to be used in a device.

Procedure:

1. Know the Working of the Breadboard

2. Analyze the circuit diagram

3. Get required components

4. Follow the breadboard diagram for the circuit, connecting one component at a time.

5. Insert the components on breadboard

6. Give power supply.

7. Always connect the batteries or power supply to your circuit last.

Result:

https://www.pcbtrain.co.uk/products-and-services/surface-mount/

http://www.pcbtrain.co.uk/blog/wp-content/uploads/2015/08/shutterstock_88863952forweb.jpg



Exp.no:9 Dates:

Familiarization with Computer Hardware &Operating System

Aim: (A) To identify the internal parts of a computer, and its Peripherals.

Apparatus required:

PC, printer, scanner, and other available devices and parts Internal hardware components are

motherboard, processor, chipset, hard disk, CMOS, RAM, BIOS, SMPS.

Theory:

Computer is an electronic device which takes the input information from the input device and

generates the output information and it will be displayed on the output. It enables arithmetic

computations, data processing, information management (storage) and knowledge reasoning in

an efficient manner.

BLOCK DIAGRAM OF COMPUTER

.

Fig (9a) (1): BLOCK DIAGRAM OF COMPUTER



Central Processing Unit (Processor):

It is the main execution component. System on Chip (SoC) type processors contains control

unit, ALU and Cache memory. Intel is the largest processor manufacturer for Desktops and

Servers, but not for smart phones.. Intel Celeron G 470 is one of the cheapest processor. Intel

core series is popular one. Core i5 and Core i7 are apt for graphic uses.

Fig (9a) (2): Central Processing Unit (Processor)

Motherboard: is the most important h/w component as all other components are connected to

it and Communicate through it. Intel makes the best motherboards, suitable for their processors.

Gigabyte and Asus also make low cost motherboard brands compatible for Intel and AMD

processors. USBports, graphics, sound, wifi, BT etc are integrated in motherboard.

Fig (9a) (3): Motherboard



Key Board:

Key board is like a type writer, which contains keys to feed the data or information into the

computer. Keyboards are available in two modules. These are: i. standard key board with 83-88

keys ii. Enhanced key board with 104 keys or above

Fig (9a) (4): Keyboard

Mouse:

Every mouse has one primary button (left button) and one secondary button (right button). The

primary button is used to carry out most tasks, where as secondary button is used in special cases

you can select commands and options

Fig (9a) (5): Mouse

Monitor: Monitor of a computer is like a television screen. It displays text characters and graphics in

colors or in shades of grey. The monitor is also called as screen or display or CRT (cathode ray

tube). In the monitor the screen will be displayed in pixels format.

i. 800 by 600 pixels

ii. 1024 by 768 pixels

Fig (9a) (6): Monitor



Printer:

A device that prints images (numbers, alphabets, graphs, etc…) on paper is known as Printer. We

have different types of printers to take printouts. These are as follows:

i. Dot matrix printer ii. Inkjet printer iii. Laser printer

Fig (9a) (7): Printer

USB (Universal serial bus):

USB is the General-purpose connection for PC. You can find USB versions of many different

devices, such as mice, keyboards, scanners, cameras, and even printers. a USB connector's

distinctive rectangular shape makes it easily recognizable. USB has a number of features that

makes it particularly popular on PCs. First, USB devices are hot swappable. You can insert or

remove them without restarting your system.

Fig (9a) (8): USB (Universal serial bus)

Parallel port:

Most printers use a special connector called a parallel port. Parallel port carry data on more than

one wire, as opposed to the serial port, which uses only one wire. Parallel ports use a 25-pin

female DB connector. Parallel ports are directly supported by the motherboard through a direct

connection or through a dangle.

Fig (9a) (9): Parallel port



Chipset:

It is a set of electronic components in an integrated circuit that manages the data flow between

the processor, memory and peripherals. It is usually found on the motherboard. Chipsets are

usually designed to

work with a specific family of microprocessors. Because it controls communications between the

processor and external devices, the chipset plays a crucial role in determining system

performance.

Fig (9a) (10): Chipset

Hard disk:

It saves data and files permanently. Since it is a magnetic device, it is much slower than

processor. SSD (Solid state drive) is newly used storage for same purpose of HDD. SSD can also

be used side by side

with HDD. SSD don't need electric motor to rotate disks as it don't have disks or any moving

mechanical parts as in HDD.

Fig (9a) (11): Hard disk



RAM:

Program and data has to be brought to RAM from HDD for execution.

It is mainly a semi conductor device (flip flops). So it has speed matching to that of Processor.

Size of the RAM decides speed of execution. The more the size, more data and program can

placed in RAM and quickly delivered to processor. Minimum RAM required is 2GB. 4GB is

optimum and 8GB is recommended for highend graphics/games applications. Cost doubles or

rather increases when size increases.

Fig (9a) (12): RAM

BIOS: It is a computer chip on the motherboard. This chip contains a special program that helps

the computer processor to interact and control the other components like disc drives, video cards,

sound cards, network cards,floppy drives, USB ports, hard drives, and others.

Fig (9a) (13): BIOS

CMOS: It stores information about the computer components esttings like system time, date and

other configuration settings. 3Volt CR2032 is a specification . CMOS battery gives power to

CMOS chip.

Fig (9a) (14): CMOS



SMPS:

SMPS is used to supply the power to Mother Board HDD,CD ROM, FDD. In SMPS holds a

transformer, voltage control and fan. Identification is the rectangular box shape and panel name

is switching mode power supply.

Fig (9a) (15): SMPS

Speakers:

Speakers make your system much more delightful to use entertain you while you are working on

computer

Fig (9a) (16): Speakers

Scanner:

Scanner used to scan images and text

Fig (9a) (17): Scanner



Procedure:

1. Take all the tools and place it on the table.

2. Study about each tool thoroughly.

Result:



Aim: (B) Assembling and disassembling the system hardware components of the personal

computer

Apparatus required:

Mother Board, CPU, RAM, SMPS, Hard Disk Drive, CD ROM, IO Devices

Theory:

Computer is an electronic device which takes the input information from the input device and

generates the output information and it will be displayed on the output. It enables arithmetic

computations, data processing, information management (storage) and knowledge reasoning in

an efficient manner.

Procedure:

Dis-assemble a PC and physically demonstrate the internal components, connections, ports. Later

reassemble and confirm the physical connections. It’s optional to demonstrate networking

devices

1. Mother Board Installation:

a. Open the cabinet on either side.

b. The back side of the cabinet has readymade provision for the installation of the I/O shields. An

I/O shield is used for connecting the input and output devices through it.

C. Check whether the mother board is placed in such a way that the I/O ports of the motherboard

correctly fit in the I/O shields. Ensure all the specified screws for the motherboard are fixed and

intact.



CPU Installations:

1. CPU is one of the most dedicated components of the computer. The CPU pins have to

be clearly studied before fixing into the relevant processor space on the motherboard.

After the CPU is rightly placed in its position the lever is to be locked.

2 As a part of the CPU installation, before the CPU is fixed in the right position a lever is

provided, which needs to be unlocked. This lever is perpendicular to the motherboard.

3 The CPU, which is a square shaped electronic component, comes with pins below it. One

should find for an indication on one of the corners of the CPU on both sides. This arrow mark is

also found on the motherboard which guides for the fixation of the CPU. Once match of the pins

verses motherboard slot gently push the CPU.



4 After the CPU is rightly placed in its position, the lever is to be locked.

CPU heat sink fan installation:

5 The CPU heat sink fan is to be carefully plugged on to the CPU by pushing down the metal

plastic clips.

6 The metal/plastic clips provided with heat sink fan should fix on to the CPU socket and have to

be locked.

7 Once the CPU het sink fan is fixed and locked, it should be connected to the Power supply

available on the mother board through the power connector.

RAM Installation:

8 Next is installing the RAM. Insert the RAM into an available expansion socket. Note how the

RAM is keyed to the socket. This ensures the RAM can be plugged into the socket one way only.

Finally press the RAM firmly into position, making certain the Ram is completely seated in the

socket.



SMPS Installations:

9 Next is installing the SMPS. This is an electronic power supply unit that provides and regulates

the power supply to all components of a computer system. As shown in the diagram the SMPS

needs to install into cabinet at the place provided for it.

10 After placing the SMPS into the relevant provider space fix the outer screws to it intact.

11 Next installing the ATX power connector. It is a 20/24-pin power connector. This is the

primary power supply to the mother board.



Hard Disk Drive Installation:

12 Installing the Hard Disk Drive (HDD) is clearly understood in the following steps. First see

the rare of the HDD. It consists of the 3 types of pins. One left side the HDD has multiple pins

termed as the IDE connector. In the middle is the jumper setting pins for the HDD. On the

extreme right side is the power connector pins. Every device except FDD (floppy Disk Drive)

uses this type of power connector. And HDD and CDD (Compact Disk Drive) connected by this

type of IDE cable.

13 Mount the HDD into mounting slot meant for the HDD with the rear end facing and secure

the inner screws intact.

14 Connect the IDE cable to the HDD as well as the mother board as shown in the figure.



15 Remember for all the power connectors to be plugged in, one needs to align the Red line on

the cable to Pin-1 of the IDE port. Hence connect the power cable to the

HDD rare end by gently pushing the connector.

CD ROM Installation:

16 Next installing the CD-ROM. Remove the cover of front side of the cabinet curtaining of the

CD-ROM.

17 Push CD-ROM case into opened space.



18 Secure CD-ROM with inner screws.

19 Connect the one end of cable to motherboard and another end to CD-ROM

20 Connect the power connector to the CD-ROM

IO Devices Installations:

21 Finally connect all peripheral devices like mouse, key-board, monitor, etc, to the I/O ports

shown in the figure below.



a) Keyboard:

Keyboard has round shape connectors. The male connector appears at the edge of the keyboard‟s

cable and the female connector appears at the back side of the system unit. We are using the 6

pins round keyboard connector.

b) Mouse:

The mouse connector is same as the keyboard connector. The male connector appears at the edge

of mouse cable and female connector appears at the backside of the system. It is also having 6

pins to connect the mouse.

c) Monitor:

The monitor of computer has „D‟ shape connectors. The male Monitor connector has 15 pins

and it appears at the edge of monitor‟s cable. The female monitor connector appears at the back

of the system unit. 19

d) Printer:

Printer connector is the oldest connector of a computer. The male printer connector has 25 pins

and it appears at the edge of the printer cable and the backside of the system unit.

e) Audio / Speaker:

3. The third symbol displays “Mic-in”.

Line-out - it sends the out put to speakers.

Line-in-- it takes the input from speakers.

Mic-in - it takes the input from microphone.



f) Ethernet / Networking:

The Ethernet connectors are used when two or more than two computers need to be linked with

other over a computer network like LAN (local area network). The shape of male Ethernet

connector is quite similar to male modem connector except it is more flat. The female Ethernet

connector appears at the back of the system unit.

g) USB:

USB (universal serial bus) is the latest and most popular connector. Using USB connectors, we

can connect so many different devices to our computer. Any device equipped with USB has slim

male connector with slim metal coating appearing at the end of the devices cable. For connecting

the device, a female USB connector is provided at the back of the system unit. We can identify

the USB connector with this symbol.

Results:



Aim: (C) To install operating system on the computer.

Apparatus required:

PC, Windows 7 Installation disk, Drivers CD

Theory: An operating system is an intermediary between user and computer h/w. OS has two parts, shell

and kernel. Different types of OS are required for different systems viz desktop, real time,

embedded server, Smartphone, workstations, mainframe, and super computer systems

Procedure:

Demonstrate following steps.

Step1. Insert the Windows 7 operating system disk into your DVD drive, and then restart your

computer

Step2. You will see a prompt that says ‘Press any key to continue’ after the ZT logo

disappears. When you see this press any key immediately.

Fig.1

Step3. ‘Starting Windows’ with the Windows7 logo will appear.



Fig.2

Step4. Language options, by default English will be set along with “time and currency format”

and “keyboard or input method”

Fig.3

Step5. Click “Install Now”

Fig. 4

Step6. End User License Agreement (E.U.L.A.), check the box to accept, and click “Next”



Fig. 5

Step7. “Which type of installation?” window will appear. Upgrade will be greyed out; the only

option you should be able to choose is Custom

Fig.6

Step8. “Where do you want to install windows?” Make sure the partition is highlighted.

Step9. Delete the partition by clicking on Drive options (advanced) on the bottom right corner of

the field. Make sure the partition is highlighted and click on Delete. If drive advanced options is

greyed out, then the partition will not have to be deleted.

*NOTE: Deleting the partitions will erase all data on the system



Fig. 7

Step10. Disk 0 Unallocated Space should be the only listing at this point. If it is press next, If not

please proceed to delete any additional partitions that may be listed.

Fig. 8

Step11. The next screen will show “Installing Windows”. This process should take

approximately 10 minutes after which the system will reboot

*NOTE: Do not press any keys during this boot up process so as to not disturb the rest of the

installation.

Step12. The next screen will show “Installing Windows” again to complete the installation

process.



Fig.9

Step13. “Setup is starting Windows” will appear on the screen, then you will be asked to create a

user name and a computer name.

Fig.10

Step14. The next step will prompt you to create a password for your account (optional).

Fig.11

Step15. The next screen will come up and ask you to choose one of three options: “Use

recommended settings”, “Install important updates only” and “Ask me later”.



Fig. 12

Step16. This screen will allow you to choose your local time zone and also adjust the date and

time.

Fig. 13

Step17. Click on the appropriate location of your computer to enable Windows 7 to apply the

correct network settings.

Fig. 14

The installation is done! You have successfully installed Windows 7 on your ZT computer

Results:



Exp.no:10 Date:

Familiarization with Office Tools

Aim: (A) To able to create documents using the word processor tool.

Apparatus required:

PC with Ubuntu OS

Theory:

LibreOffice Writer lets us to design and produce text documents that can include graphics,

tables, or charts. We can then save the documents in a variety of formats, including the

standardized Open Document format (ODF), Microsoft Word .doc format, or HTML. And we

can easily export our document to the Portable Document Format (PDF) LibreOffice Writer lets

us to create both basic documents, such as memos, faxes, letters , resumes and merge documents,

as well as long and complex or multi-part documents, complete with bibliographies, reference

tables and indexes. LibreOffice Writer also includes such useful features as a spellchecker, a

thesaurus, AutoCorrect, and hyphenation as well as a variety of templates for almost every

purpose. We can also create our own templates using the wizards. Text documents in LibreOffice

have an integrated calculation function that helps we to execute sophisticated calculations or

logical links. We can easily create a table in a text document in order to perform calculations.

The drag-and-drop feature enables to work quickly and efficiently with text documents in

LibreOffice



Fig. 10.1 Open Microsoft Word by clicking on the program icon

Fig. 10.2 Window for a new Word document

Fig. 10.3 Screen for a newly named Word processor document



Procedure:

1. Search web to select an appropriate model for biodata and covering Letter

2. Prepare own biodata to apply for a position job w.r.t selected course of study

3. Save the file either in open format (.odt) or Microsoft format (.doc). Normally “odt” isn't

supported by paid platforms (eg: Windows). But Ubuntu supports their formats. (“Format drop

down” option is just above the “save” button in save window.)

4. Click on “save with password” check-box option, if needed. It is available on left bottom side

in save window

5. Its optional to convert the file to Portable Document Format (File->Export as PDF), so that the

file will be seen intact in all OS platforms. Also PDF is apt for printing.

6. Repeat the steps from 1 to 5 for creating a covering letter

7. Send files to the email of trainer (optional)

Result:



Aim: (B) To able to create, open, save the application documents and format them as per the

requirement.

Apparatus required:

PC with Ubuntu OS

Theory:

LibreOffice Calc is a spreadsheet application used to calculate, analyze, and manage our data.

We can also import and modify Microsoft Excel spreadsheets. It provides functions, including

statistical and banking functions that we can use to create formulas to perform complex

calculations on our data. Function Wizard to help we create our formulas. It let us to drag-and-

drop tables from databases, form letters in LibreOffice Writer, Convert Excel files, or to open

and save in a variety of other formats (eg: MS office).

Procedure:

1. Collect data and prepare sheets

2. Save the file either in open format(.ods) or Microsoft format(.xls). Normally “ods” isn't

supported by paid platforms (eg: Windows). But Ubuntu supports almost all formats. (“Format

drop down” option is just above the “save” button in save window.)


in save window



5. Send files to the email of trainer (optional)

Result :



Aim: (C) To creating, opening, saving and running the presentation, selecting the style of

slides,

Apparatus required:

PC with Ubuntu OS

Theory:

Impress has a comprehensive range of easy-to-use drawing and diagramming Tools to add style

and sophistication to your presentation. We can save even more time by downloading templates

from the LibreOffice template repository. Impress supports multiple monitors, and the

standardly-incorporated Presenter Console Extension gives you yet more control over your slide

show presentation, such as the ability to see the upcoming slide, view your slide notes, and

control the presentation timer while the audience is looking at the current slide. Create custom

slide shows to meet the needs of our audience using slides within the current presentation.

Procedure:

1. Collect data and prepare slides

2. Save the file either in open format (.odp) or Microsoft format (.ppt). Normally “odp” isn't

supported by paid platforms (eg: Windows). But Ubuntu supports their formats. (“Format drop

down” option is just above the “save” button in save window.)


in save window



5. Also try saving the file in various other formats like XML or auto play (“.pps”) (Eg: File -->

Save As Microsoft PowerPoint 97/2000/XP/2003 Auto play and open it to get familiarize with

the format)



6. Send files to the email of trainer (optional) We can change the order of the slides in our

custom slide show, by dragging and dropping the slides under Selected Slides.To start a custom

slide show:

1. Choose Slide Show –> Custom Slide Show.

2. Select the show we want to start from the list.

3. Click Start.

Result:



Exp.no:11 Date:

Familiarization of PA systems with different microphones, loud

speakers & mixers

Aim: To study and identify the different microphones, loud speakers & mixers

Apparatus required:

microphones, loud speakers & mixers

Theory:

Microphones:

Microphones are an essential part of any audio recording system. The microphone picks

up the sound and converts it into electrical energy that can then be processed by electronic

amplifiers and audio processing systems.

Fig (11 .1): Typical moving coil / dynamic microphone

Microphones come in all shapes and sizes. Also different types of microphone may use different

technologies. These different types of microphone have different properties, and therefore

knowledge of the various forms of microphone will enable the best microphone type to be

chosen for a given application.

In terms of their technology, most microphones use electromagnetic induction (dynamic

microphones), capacitance change (condenser microphones) or piezoelectricity (crystal or

ceramic microphones) to produce an electrical signal from air pressure variations.



Microphones produce very small output signal levels. Accordingly they need to be connected to

a preamplifier before the signal can be recorded or reproduced.

A knowledge of the different types of microphone also enables the way it is used to play to its

strengths. So even if you are not a tecchie, it helps to know a little about them to use them to

their best.

Microphone parameters

When choosing a microphone for any given application, it is necessary to take account of the

various attributes, specifications and performance parameters that it has.

Some of the key parameters for microphones include:

• Fidelity

• Sensitivity

• Frequency response

• Directional attributes

• Robustness

• Cost

• Convenience of use

• Appearance

The importance of the different microphone parameters will depend upon the application. Before

making a choice of any given microphone it is necessary to decide what is important.

• Type of microphone:

There are many different types of microphone that are a available. Each type of microphone has

its own attributes, and different types of microphone are used in different applications so that the

best performance can be achieved under any given circumstances.

The different types of microphone can be categorised in a number of different ways. Dependent

upon the application, different approaches may be applicable. Sometimes the different types may



be differentiated by they technology, other times it may be by the directional properties, and

sometimes it may be by the diaphragm diameter.

Moving coil / dynamic microphone: This type of microphone is widely used for stage

performances and many other applications. The moving coil microphone, has a small cone with a

coil wound at its apex. This is held in a magnetic field and a current is induced in the coil as it

moves in line with the sound vibrations.

Condenser microphone: The condenser microphone consists of a capacitor of which one plate

is the microphone diaphragm. As sound waves hit the diaphragm, it vibrates and causes changes

in capacitance. This can be converted into changes in voltage. The condenser microphone gains

its name from the fact that when it was invented, capacitors were called condensers.

Electret microphone : This type of microphone is effectively a derivative of the condenser

microphone type. It is electrostatic capacitor-based and this eliminates the need for a polarizing

power supply by using a permanently charged material. Although the technology has been used

for some higher end microphones, it is normally associated with small microphones for use in

electronic equipment. Here its size, and low cost of manufacture make it ideal for many

applications where ultimate performance is not needed.

Ribbon microphone : This is a form of high quality microphone that was widely used in the

radio industry. Now it is less widely used as other types can offer equal performance more

conveniently. It typically consists of a narrow aluminium ribbon which is corrugated to make it

flexible. It is suspended between the poles of a magnet so that when the aluminium diaphragm

moves, then a current is induced in the electrical circuit.

Crystal / ceramic: The crystal or ceramic microphone uses the piezo-electric effect to generate

voltages. It is found that certain substances create a voltage across them when they are stressed.

In a crystal or ceramic microphone a diaphragm is attached to a slice of piezo-electric material

and the sound vibrations pass to the diaphragm which in turn passes them to the piezo-electric

crystal.



Boundary microphone / PZM: The bounadary microphone offers a number of advantages over

other types. It uses the boundary between the air and hard surfaces like a wall or a floor to

enhance the sensitivity and also provide other enhancements to adding more naturalness to the

sound etc. One popular incarnation of the boundary microphone is know as the PZM or pressure

zone microphone. This name was introduced by the Crown Corporation for their incarnation of

the technology.

Carbon microphone: The carbon microphone was the first practicable form of microphone and

as a result it was used for many years was the main type of microphone available. It was based

on the fact that when carbon crystals are compressed, their resistance reduces

Loudspeakers:

Loudspeakers have been used for many years to convert electrical signals into audio

sound waves.

Although the basic principles of the loudspeaker are relatively easy to grasp, the actual design of

a high quality unit is not simple: designing one and optimising it for the best sound is a difficult

process.

Loudspeakers are complex as the performance depends upon that of the loudspeaker units

themselves, how they are combined, if more than one is used in a system, and how the speakers

interact with the enclosure. They are even affected by their surroundings, the amplifier and a

number of other factors. A typical loudspeaker unit



Fig (11 .2): Loudspeakers:

Loudspeaker for home use with three types of dynamic drivers

1. Mid-range driver

2. Tweeter

3. Woofers

The hole below the lowest woofer is a port for a bass reflex system.

Loudspeaker basics

The purpose of a loudspeaker is to convert an electrical signal into sound waves providing the

most faithful reproduction that is feasible for its design.

There is obviously a very wide range in the quality of loudspeakers. Cost size, and many other

factors contribute to the overall quality.

Often loudspeakers are taken for granted. They are either contained within a radio or other audio

player, or possibly within a loudspeaker system, possibly containing two or more loudspeaker

drive units.

There are a number of different loudspeaker drive unit technologies as described below. These

can then be contained within different types of enclosures. Each factor needs to be taken into

consideration when designing or selecting a loudspeaker system.

Loudspeaker types & technologies

There are several different technologies and approaches used within loudspeakers. As a result

there are several different types of loudspeaker that can be used, and mention of these will be

often be seen in the literature.

Moving coil: The moving coil type of loudspeaker is the type that is most commonly seen. It

consists of a cone attached to a coil that is held within a magnetic field. The moving coil

https://en.wikipedia.org/wiki/Bass_reflex



loudspeaker s the type which everyone thinks about when looking for a loudspeaker unit. It

basically consists of a diaphragm, typically attached to a coil though which the audio is passed.

Cross section through a typical moving coil loudspeaker. The coil is suspended within a

magnetic field and this means that the variations in current flow resulting from the electrical

audio signal cause the coil, and hence the cone to move. This results in the loudspeaker

converting the electrical audio signal into sound.

Horn: The horn loudspeaker type is often used for tweeters. Although it uses the same

electromagnetic effect as the moving coil loudspeaker, a diaphragm held within a magnetic field

that is varied in line with the audio. This causes the diaphragm to vibrate and these vibrations are

then magnified by a horn.

Horn loudspeakers are used in many areas of auto technology, and although they are used to

good effect in some high quality applications, they tend to be found more widely in public

address and outside uses.

The horn loudspeaker consists of a transducer, which is often a moving coil transducer, and this

is connected to a horn. This can be thought of a matching element very similar to a waveguide

horn antenna, and this enables much higher levels of efficiency to be obtained. This could be

noticed on old gramophones that used a horn to enable the sound to reach usable levels. Without

the horn, the gramophone sound was almost inaudible.

Electrostatic: The electrostatic loudspeaker type is uses a totally different principle to that of

the moving coil and horn loudspeaker types. Instead the electrostatic loudspeaker is one in

which sound is generated by utilising the force exerted on a membrane suspended in an

electrostatic field.

These are various other technologies can all be used to create loudspeakers.

Loudspeaker systems

Loudspeaker systems vary enormously. Some only have a single drive unit or loudspeaker unit,

but often these single speaker systems have limited response at the low and high frequency ends

of the frequency spectrum.

As a result many systems consist of two or even three different loudspeaker drive units, each

targeted at covering a different frequency range.

Typical type of loudspeaker system

It can be seen from the diagram above of a typical hi-fi loudspeaker system, that there are several

elements to the overall system.



• Loudspeaker drive units: The loudspeaker units themselves are of paramount importance as

they convert the electrical currents into sound waves. Hi-Fi loudspeakers may have one or

more loudspeakers of the different types mentioned below. For free standing systems two and

sometimes there speakers with different ranges are used.

• Cross-over unit: If multiple speakers are used, then it helps to have the required frequencies

routed to the relevant speakers. Traditionally crossover units tended to consist of inductor and

capacitors and many still do today. Modern amplifiers sometimes have different outputs for

low end and top end speakers, so into is case the crossover unit is effectively contained within

the amplifier.

• Cabinet: There are many different types of loudspeaker cabinet. Often an infinite baffle

system is used, that consists of a closed box. This needs to be as rigid and airtight as possible

to ensure that the only vibrations come from the loudspeakers themselves. Accordingly these

boxes are made from very rigid wood or other material.

• Internal sound absorbed material: To prevent resonances being set up inside the

loudspeaker cabinet, sound absorbed material is used within the infinite baffle systems.

Loudspeaker enclosures

Most loudspeakers are mounted in an enclosure or cabinet. This not only protects the

loudspeaker from damage, but it also enhances the performance of the sound.

Some hi-fidelity systems can cost significant amounts. A huge amount of design can be invested

in the loudspeaker cabinet.

Several different types of cabinet and mounting system are used: baffle including the infinite

baffle, doublet, infinite baffle, reflex, column, transmission line and more.

Each of these different types of loudspeaker enclosure has its own advantages and disadvantages

and can be used to its best effect in different situations.

Electronic mixer :

Fig (11 .3): Electronic mixer

An electronic mixer is a device that combines two or more electrical or electronic signals into

one or two composite output signals. There are two basic circuits that both use the term mixer,

https://en.wikipedia.org/wiki/Electronics

https://en.wikipedia.org/wiki/Signal_(information_theory)



but they are very different types of circuits: additive mixers and multiplicative mixers. Additive

mixers are also known as "analog adders" to distinguish from the related digital adder circuits.

Procedure:

1. Take all the components and place it on the table.

2. study and identify the different microphones, loud speakers & mixers

Result:

https://en.wikipedia.org/wiki/Adder_(electronics)



Exp.no:12 Date:

Understanding working of various communication systems

Aim: To study the working of various communication systems like, Radio receiver, Television,

Satellite transmitter & receiver, mobile phone.

Apparatus required:

Radio receiver, Television, Satellite transmitter & receiver, mobile phone.

Theory:

Radio:

Radio is the radiation (wireless transmission) of electromagnetic energy through space. All of

you are fond of tuning in to your favourite radio channel to listen to the programs you like the

most.Have you ever wondered how these programs reach from the distantly placed radio stations

to your radios and music systems

Radio signals are created by two kinds of waves: sound waves that represent the sounds being

sent to the audience and the radio frequency waves that carry the sound waves to radios in homes

and cars. Let us understand the whole process in detail.

Interesting Facts about Radio • Wireless radio was discovered by a German inventor, Heinrich

Hertz, in the late 1800s. • An Italian inventor, Guglielmo Marconi, is known as the ‘Father of

Radio’ because he made practical and useable radio sets based on the Hertz discovery. • Radio

waves travel at the speed of light- 186,282 miles per second.

Interesting Facts about Radio • Radio waves transmit music, talks, pictures and information

invisibly through the air, often over millions of kilometres—it happens every day in thousands of

different ways! • There are a vast number of everyday technologies that depend on radio waves

apart from the radio broadcasts. Cordless phones, cell phones, radio controlled toys, television

broadcasts and satellite communication—everything depends on the radio waves. Even gadgets

like radar and microwave ovens use radio waves.



Radio Receiver:

In radio communications, a radio receiver, also known as a receiver, wireless or

simply radio is an electronic device that receives radio waves and converts the information

carried by them to a usable form. It is used with an antenna. The antenna intercepts radio waves

(electromagnetic waves) and converts them to tiny alternating currents which are applied to the

receiver, and the receiver extracts the desired information. The receiver uses electronic filters to

separate the desired radio frequency signal from all the other signals picked up by the antenna,

an electronic amplifier to increase the power of the signal for further processing, and finally

recovers the desired information through demodulation.

The information produced by the receiver may be in the form of sound, moving images

(television), or data. A radio receiver may be a separate piece of electronic equipment, or

an electronic circuit within another device. Radio receivers are very widely used in modern

technology, as components of communications, broadcasting, remote control, and wireless

networking systems. In consumer electronics, the terms radio and radio receiver are often used

specifically for receivers designed to reproduce sound transmitted by radio broadcasting stations,

historically the first mass-market commercial radio application.

The most familiar form of radio receiver is a broadcast receiver, often just called a radio, which

receives audio programs intended for public reception transmitted by local radio stations. The

sound is reproduced either by a loudspeaker in the radio or an earphone which plugs into a jack

on the radio. The radio requires electric power, provided either by batteries inside the radio or a

power cord which plugs into an electric outlet. All radios have a volume control to adjust the

loudness of the audio, and some type of "tuning" control to select the radio station to be received.

Radio receivers are essential components of all systems that use radio. Besides broadcast

receivers, described above, radio receivers are used in a huge variety of electronic systems in

modern technology. They can be a separate piece of equipment (a radio), or a subsystem

incorporated into other electronic devices. A transceiver is a transmitter and receiver combined

in one unit. Below is a list of a few of the most common types, organized by function

Fig (12 .1): radio receiver

https://en.wikipedia.org/wiki/Radio

https://en.wikipedia.org/wiki/Radio_wave

https://en.wikipedia.org/wiki/Antenna_(radio)

https://en.wikipedia.org/wiki/Electromagnetic_wave

https://en.wikipedia.org/wiki/Alternating_current

https://en.wikipedia.org/wiki/Electronic_filter

https://en.wikipedia.org/wiki/Radio_frequency

https://en.wikipedia.org/wiki/Electronic_amplifier

https://en.wikipedia.org/wiki/Demodulation

https://en.wikipedia.org/wiki/Television

https://en.wikipedia.org/wiki/Electronic_circuit

https://en.wikipedia.org/wiki/Consumer_electronics

https://en.wikipedia.org/wiki/Radio_broadcasting

https://en.wikipedia.org/wiki/Commercial_radio

https://en.wikipedia.org/wiki/Audio_signal

https://en.wikipedia.org/wiki/Radio_station

https://en.wikipedia.org/wiki/Loudspeaker

https://en.wikipedia.org/wiki/Earphone

https://en.wikipedia.org/wiki/Electric_power

https://en.wikipedia.org/wiki/Battery_(electricity)

https://en.wikipedia.org/wiki/Electric_outlet

https://en.wikipedia.org/wiki/Loudness

https://en.wikipedia.org/wiki/Radio

https://en.wikipedia.org/wiki/Transceiver

https://en.wikipedia.org/wiki/Transmitter



Television :

Television or TV is a telecommunication medium used for transmitting moving images in

monochrome (black-and-white), or in color, and in two or three dimensions and sound. • The

term can refer to a television set, a television program ("TV show"), or the medium of television

transmission. Television is a mass medium for entertainment, education, news, politics, gossip,

and advertising.

Television is one of the most significant inventions of the twentieth century and has been

regarded as a powerful medium for information and entertainment. The development of

communication technology has evidently enabled television industry to revolutionize itself, thus

enhancing the source of information and entertainment

The types of television

• Mechanical

• Electronic

• Color

• Digital

• Smart TV Fig (12 .2): Smart TV

• 3D

The broadcast system • Terrestrial television • Cable television • Satellite television • Internet

television

Broadcast television reception - Televisions receive a video signal representing a moving

image, composed of a sequence of still images, and a synchronized audio signal representing the

associated sound. The channel received by a TV occupies a wider bandwidth than an audio

signal, from 600 kHz to 6 MHz.

https://en.wikipedia.org/wiki/Video_signal

https://en.wikipedia.org/wiki/Audio_signal

https://en.wikipedia.org/wiki/Bandwidth_(signal_processing)



• Terrestrial television receiver, broadcast television or just television (TV) - Televisions

contains an integral receiver (TV tuner) which receives free broadcast television from

local television stations on TV channels in the VHF and UHF bands.

• Satellite TV receiver - a set-top box which receives subscription direct-broadcast satellite

television, and displays it on an ordinary television. A rooftop satellite dish receives many

channels all modulated on a Ku band microwave downlink signal from a geostationary direct

broadcast satellite 22,000 miles (35,000 km) above the Earth, and the signal is converted to a

lower intermediate frequency and transported to the box through a coaxial cable. The

subscriber pays a monthly fee.

Satellite:

A communications satellite is an artificial satellite that relays and amplifies

radio telecommunications signals via a transponder; it creates a communication channel

between a source transmitter and a receiver at different locations on Earth.

Fig (12 .3): Satellite

Basic Elements

Satellite communications are comprised of 2 main components:

• The Satellite

The satellite itself is also known as the space segment, and is composed of three separate

units, namely the fuel system, the satellite and telemetry controls, and the transponder.

The transponder includes the receiving antenna to pick-up signals from the ground

station, a broad band receiver, an input multiplexer, and a frequency converter which is

used to reroute the received signals through a high powered amplifier for downlink. The

primary role of a satellite is to reflect electronic signals. In the case of a telecom satellite,

the primary task is to receive signals from a ground station and send them down to

another ground station located a considerable distance away from the first. This relay

action can be two-way, as in the case of a long distance phone call. Another use of the

satellite is when, as is the case with television broadcasts, the ground station's uplink is

https://en.wikipedia.org/wiki/Television_receiver

https://en.wikipedia.org/wiki/TV_tuner

https://en.wikipedia.org/wiki/Broadcast_television

https://en.wikipedia.org/wiki/Television_station

https://en.wikipedia.org/wiki/TV_channel

https://en.wikipedia.org/wiki/Very_high_frequency

https://en.wikipedia.org/wiki/Ultrahigh_frequency

https://en.wikipedia.org/wiki/Satellite_TV

https://en.wikipedia.org/wiki/Set-top_box

https://en.wikipedia.org/wiki/Direct-broadcast_satellite_television

https://en.wikipedia.org/wiki/Direct-broadcast_satellite_television

https://en.wikipedia.org/wiki/Television

https://en.wikipedia.org/wiki/Satellite_dish

https://en.wikipedia.org/wiki/Ku_band

https://en.wikipedia.org/wiki/Microwave

https://en.wikipedia.org/wiki/Downlink

https://en.wikipedia.org/wiki/Geostationary

https://en.wikipedia.org/wiki/Direct_broadcast_satellite

https://en.wikipedia.org/wiki/Direct_broadcast_satellite

https://en.wikipedia.org/wiki/Intermediate_frequency



then down linked over a wide region, so that it may be received by many different

customers possessing compatible equipment. Still another use for satellites is observation,

wherein the satellite is equipped with cameras or various sensors, and it merely

downlinks any information it picks up from its vantage point.

• The Ground Station.

This is the earth segment. The ground station's job is two-fold. In the case of an uplink, or

transmitting station, terrestrial data in the form of baseband signals, is passed through a

baseband processor, an up converter, a high powered amplifier, and through a parabolic

dish antenna up to an orbiting satellite. In the case of a downlink, or receiving station,

works in the reverse fashion as the uplink, ultimately converting signals received through

the parabolic antenna to base band signal.

Various Uses of Satellite Communications

• Traditional Telecommunications

Since the beginnings of the long distance telephone network, there has been a need to

connect the telecommunications networks of one country to another. This has been

accomplished in several ways. Submarine cables have been used most frequently.

However, there are many occasions where a large long distance carrier will choose to

establish a satellite based link to connect to transoceanic points, geographically remote

areas or poor countries that have little communications infrastructure. Groups like the

international satellite consortium Intelsat have fulfilled much of the world's need for this

type of service.

• Cellular

Various schemes have been devised to allow satellites to increase the bandwidth available

to ground based cellular networks. Every cell in a cellular network divides up a fixed

range of channels which consist of either frequencies, as in the case of FDMA systems,

or time slots, as in the case of TDMA. Since a particular cell can only operate within

those channels allocated to it, overloading can occur. By using satellites which operate at

a frequency outside those of the cell, we can provide extra satellite channels on demand

to an overloaded cell. These extra channels can just as easily be, once free, used by any

other overloaded cell in the network, and are not bound by bandwidth restrictions like

those used by the cell. In other words, a satellite that provides service for a network of

cells can allow its own bandwidth to be used by any cell that needs it without being

bound by terrestrial bandwidth and location restrictions.



• Television Signals

Satellites have been used for since the 1960's to transmit broadcast television signals

between the network hubs of television companies and their network affiliates. In some

cases, an entire series of programming is transmitted at once and recorded at the affiliate,

with each segment then being broadcast at appropriate times to the local viewing

populace. In the 1970's, it became possible for private individuals to download the same

signal that the networks and cable companies were transmitting, using c-band reception

dishes. This free viewing of corporate content by individuals led to scrambling and

subsequent resale of the descrambling codes to individual customers, which started the

direct-to-home industry. The direct-to-home industry has gathered even greater

momentum since the introduction of digital direct broadcast service.

Satellite transmitter :

Fig (12 .4): Satellite transmitter

Satellite transmitter -a transmitter on communications satellite an artificial satellite that

relays signals back to earth; moves in a geostationary orbit. sender, transmitter - set used to

broadcast radio or tv signals.

satellite receiver:

Fig (12 .5): Satellite Receivers

The signals are received via an outdoor parabolic antenna commonly referred to as a

satellite dish and a low-noise block down converter. A satellite receiver then decodes the

desired television programme for viewing on a television set. Receivers can be external set-top

boxes, or a built-in television tuner.



Mobile phones:

Mobile phones as communicative tools have resulted into fast-pacing a communication session.

It is because of mobile phones that we are sure of an any-time any-where communication

possibility. Today let it be a business deal or a personal communication necessity, a mobile

number is just enough to guide a necessary soul to the destination of the desired one, that too

within a blink of an eye lid. It is because of this portable communication tool that loved ones at

any corner of this vast world can be reached to. No wonder why it is amongst the most popular

gadgets of this modern world. With a mobile phone in one hand, communicating anyone in this

world has become just a so easy process today.

Mobile Phone works on Cellular Network Technology. A cellular network is a network of

wireless links. An area on Earth is divided into cells. Shape of these cells can be hexagonal,

square, rectangular, circular or any other shapes. But hexagonal shape is most preferred to create

cells of a cellular network. Each of these cells has their own base transceiver stations. These base

stations provide wireless network coverage to the cell. These wireless frequencies can be used

for transmission of voice, data, FM radio content etc. Different set of frequencies are used by

each cell to avoid conflict with the neighboring cells.

Growth and development of Electronics and Technology has made Modern Mobile Cell Phones

more useful with an array of features that make our lives even more convenient. With a Mobile

Cell Phone you can:

1. Store contact information with mobile numbers and other contact details such as other

phone numbers, home and office address, email address etc.

2. Create to-do lists and set reminders so that your mobile reminds you on a particular date and

time that you have a task to do. This is extremely useful if you have a bad memory.

3. Use Calculator so that you can do that complex math without making any mistake.

4. Send and receive e-mail, Get information (news, entertainment, stock quotes), Play games,

Watch TV, Send SMS and MMS.

5. Integrate other devices such as PDAs, MP3 players and GPS receivers.

6. Connect to security devices to have a direct view of the security cameras.

http://www.electronicsandyou.com/blog/



Fig (12 .5): Mobile phones:

Procedure:

1. Take all the components .

2. Study the working of various communication systems like, Radio receiver, Television, Satellite

Transmitter & receiver, mobile phone

Result:

electronics & communication engineering workshop...

Documents