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Jawaharlal Nehru Engineering College

Laboratory Manual

EDC-I

For

Second Year Students

Manual made by

A.A.Sayar

” Author JNEC, Aurangabad

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MGM’S

Jawaharlal Nehru Engineering CollegeN-6, CIDCO, Aurangabad

Department of Electronics &TelecommunicationVision of the Department:

To develop GREAT technocrats and to establish centre of excellence in the field of Electronics

and Telecommunications.

} Global technocrats with human values

} Research and lifelong learning attitude,

} Excellent ability to tackle challenges

} Awareness of the needs of society

} Technical expertise

Mission of the Department:

1. To provide good technical education and enhance technical competency by providing

good infrastructure, resources, effective teaching learning process and competent, caring

and committed faculty.

2. To provide various platforms to students for cultivating professional attitude and ethical

values.

3. Creating a strong foundation among students which will enable them to pursue their

career choice.

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Jawaharlal Nehru Engineering College

Technical DocumentThis technical document is a series of Laboratory manuals of Electronics & Telecommunication and is a certified document of Jawaharlal Nehru Engineering College. The care has been taken to make the document error free but still if any error is found kindly bring it to the notice of subject teacher and HOD.

Recommended by,

HOD

Approved by,

Principal

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FOREWORD

It is my great pleasure to present this laboratory manual for second year engineering students for the subject of Electronic Devices &circuits-I to understand and visualize the basic concepts of various circuits using ICs. Electronic Devices &circuits-I covers basic concepts of electronics. This being a core subject, it becomes very essential to have clear theoretical and designing aspects.

This lab manual provides a platform to the students for understanding the basic concepts of electronic devices and circuits. This practical background will help students to gain confidence in qualitative and quantitative approach to electronic circuits.

Good Luck for your Enjoyable Laboratory Sessions.

PROF.A.A.Sayar

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LABORATORY MANUAL CONTENTS

This manual is intended for the Second Year students of ECT/IE branches in the subject of Electronic Devices & Circuits-I. This manual typically contains practical/ Lab Sessions related to Electronic Devices & Circuits covering various aspects related to the subject for enhanced understanding.

Students are advised to thoroughly go through this manual rather than only topics mentioned in the syllabus as practical aspects are the key to understanding and conceptual visualization of theoretical aspects covered in the books.

Good Luck for your enjoyable Laboratory Sessions.

PROF.A.A.Sayar

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SUBJECT INDEX:

1. Do’s & Don’ts in Laboratory.

2. Lab Exercises1. To plot VI characteristic of PN junction diode.2. For half wave rectifier with capacitor filter find the ripple factor.3. For Full wave bridge rectifier with capacitor filter find the ripple factor.4. To plot the output V-I characteristics of Bipolar Junction Transistor.5. To plot the drain characteristics of N-channel JFET.6. To plot the drain characteristics of N-channel MOSFET.7. To study the circuit of Colpitts or LC Oscillator & Determine the frequency

of Oscillator.8. To study the circuit of RC Phase shift Oscillator & Determine the frequency

of Oscillator.

3. Quiz4. Conduction of viva voce examination 5. Evaluation & marking scheme

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Do’s and Don’ts in Laboratory :-

1. Do not handle any equipment before reading the instructions /Instruction manuals.

2. Read carefully the power ratings of the equipment before it is switched ON, whether ratings 230 V/50 Hz or 115V/60 Hz. For Indian equipment, the power ratings are normally 230V/50Hz. If you have equipment with 115/60 Hz ratings, do not insert power plug, as our normal supply is 230V/50Hz., which will damage the equipment.

3. Observe type of sockets of equipment power to avoid mechanical damage.4. Do not forcefully place connectors to avoid the damage.5. Strictly observe the instructions given by the Teacher/ Lab Instructor.

Instruction for Laboratory Teachers:-

1. Submission related to whatever lab work has been completed should be done during the next lab session.

2. Students should be instructed to switch on the power supply after getting the checked by the lab assistant / teacher. After the experiment is over, the students must hand over the circuit board, wires, CRO probe to the lab assistant/teacher.

3. The promptness of submission should be encouraged by way of marking andevaluation patterns that will benefit the sincere students.

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Exercise No.1 :(2 Hours)

Aim:- To plot VI characteristic of PN junction diode.

Apparatus:- D.C. regulated power supply (0-30V) , Diode(1N4007), Resistance(1K Ω), voltmeter(0-10V), ammeter (0-25mA), Connecting wires.

Circuit Diagram:-

Procedure:-

1. Connect the circuit as shown in fig.2. By varying applied voltage measure corresponding reading for voltage &

Current.3. Plot the graph of voltage & forward current.

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Observations:-

Applied voltageVdc ( V)

O/P VoltageVf ( V)

CurrentIf ( mA)

12V(Variable)

0.10.20.30.40.50.60.7

Forward V-I Characteristics of PN Junction Diode :-

Result: - Current increases exponentially with respect to voltage after cut in voltage as seen from the graph.

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Exercise No.2 :(2 Hours)

Aim: - For half wave rectifier with capacitor filter find the ripple factor.

Apparatus: - Step Down transformer, Diode (1N4007), Resistance (1KΩ), capacitor (1000 µF), voltmeter, oscilloscope, connecting wires.

Circuit Diagram:-

Procedure:-

1. Connect the circuit as shown in fig.2. By applying AC input voltage measure corresponding reading for output voltage

(Peak, RMS).3. Observe the output DC voltage.4. Calculate ripple factor.

Equation:-

Ripple Factor: γ = VRMS / VDC

+C??????

RL1KΩ

D2

D1

+

-

Vin

T1

Vout

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Observations:-

Applied input peak voltage

Vin(peak)

Peak Output VoltageVout(peak)

RMS Output VoltageVout(rms)

DC Output VoltageVout(DC)

Input and Output Waveforms for Half Wave Rectifier with Capacitor Filter

Result: - Ripple Factor (Calculated) =Ripple Factor (Measured) =

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Exercise No.3 :( 2 Hours)

Aim: - For Full wave bridge rectifier with capacitor filter find the ripple factor.

Apparatus: - Step Down transformer, 04 Diodes- (1N4007), Resistance (1KΩ), capacitor (1000 µF), voltmeter, oscilloscope, connecting wires.

Circuit Diagram :-

Procedure:-

1. Connect the circuit as shown in fig.2. By applying AC input voltage measure corresponding reading for output voltage

(Peak, RMS).3. Observe the output DC voltage.4. Calculate ripple factor.

Equation:-

Ripple Factor: γ = VRMS / VDC

+

-

Vin

T1

+C??????

RL1KΩ

Vout

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Observations:-

Applied input peak voltage

Vin(peak)

Peak Output VoltageVout(peak)

RMS Output VoltageVout(rms)

DC Output VoltageVout(DC)

Input and Output Waveforms for Full Wave bridge Rectifier with Capacitor Filter

Result:- Ripple Factor (Calculated)=Ripple Factor (Measured) =

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Exercise No.4 :(2 Hours):-

Aim: - To plot the output V-I characteristics of Bipolar Junction Transistor.

Apparatus: - Transistor (BC 107), Regulated Power Supply (0-15V), Regulated Power Supply (0-30V), Voltmeter (0-20V), Ammeter (0-200μA), Ammeter (0-100mA), Resistors, Bread board, connecting wires.

Circuit Diagram :-

Procedure:-

Output characteristics:1. Connect the circuit as per the circuit diagram2. For plotting the output characteristics the input current IB is kept constant at

20μA and for different values of VCE note down the values of IC.

3. Repeat Step 2 for IB at 40μA and 60μA.4. Tabulate all the readings.5. Plot the graph between VCE and IC for constant IB.

PRECAUTIONS:1. The supply voltage should not exceed the rating of the transistor 2. Meters should be connected properly according to their polarities

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Observations:-

Sr.NoIB = 20μA IB = 40 μA IB = 60 μA

VCE(V) IC(mA) VCE(V) IC(mA) VCE(V) IC(mA)

1 0.1 0.1 0.1

2 0.2 0.2 0.2

3 0.3 0.3 0.3

4 0.4 0.4 0.4

5 0.5 0.5 0.5

6 0.8 0.8 0.8

7 1.0 1.0 1.0

8 2.0 2.0 2.0

9 3.0 3.0 3.0

10 4.0 4.0 4.0

11 5.0 5.0 5.0

Output Characteristics of BJT:

RESULT: The output characteristics of a transistor in CE configuration are drawn.

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Exercise No.5 :(2 Hours):-

Aim: - To plot the drain characteristics of N-channel JFET.

Apparatus: - JFET (BFW10), Regulated Power Supply (0-12V), Regulated Power Supply (0-30V), 02 Voltmeters (0-20V), Ammeter (0-100mA),Resistors, Bread board, connecting wires.

Circuit Diagram :-

Procedure:-

Output characteristics:1. Connect the milli ammeter & voltmeters at the respective places.2. Keep the VGG & VDD at minimum positions.3. Switch on the power supply.4. Keep the VGS at fixed value say VGS=0V5. Now increase the VDD in steps & note down the readings of ID for

corresponding values of VDS.6. Plot the graph with VDS versus ID at constant VGS.7. Repeat the steps from 4 to 6 for different values of VGS

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Observations:-

Sr.No

VGS = 0V VGS = -1V VGS = -2V VGS = -3V

VDS(V) ID(mA) VDS (V) ID(mA) VDS (V) ID(mA) VDS (V) ID(mA)

1 0.5 0.5 0.5 0.5

2 1.0 1.0 1.0 1.0

3 1.5 1.5 1.5 1.5

4 2.0 2.0 2.0 2.0

5 2.5 2.5 2.5 2.5

6 3.0 3.0 3.0 3.0

7 4.0 4.0 4.0 4.0

8 5.0 5.0 5.0 5.0

9 6.0 6.0 6.0 6.0

10 7.0 7.0 7.0 7.0

11 8.0 8.0 8.0 8.0

Drain Characteristics of JFET:

RESULT: The drain characteristics of a JFET are drawn.

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Exercise No.6 :(2 Hours):-

Aim: - To plot the drain characteristics of N-channel MOSFET.

Apparatus: - MOSFET (IRF840), Regulated Power Supply (0-12V), RegulatedPower Supply (0-30V), 02 Voltmeters (0-20V), Ammeter (0-100mA),Resistors, Bread board, connecting wires.

Circuit Diagram :-

Procedure:-

Output characteristics:1. Connect the milliammeter & voltmeters at the respective places.2. Keep the VGG & VDD at minimum positions.3. Switch on the power supply.4. Keep the VGS at fixed value at VGS=4V5. Now increase the VDD in steps & note down the readings of ID for

corresponding values of VGS.

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6. Plot the graph with VDS versus ID at constant VGS.7. Repeat the steps from 4 to 6 for different values of VGS

Observations:-

Sr.NoVGS = 4V VGS = 5V VGS = 6V

VDS(V) ID(mA) VDS (V) ID(mA) VDS (V) ID(mA)

1 0.1 0.1 0.1

2 0.2 0.2 0.2

3 0.3 0.3 0.3

4 0.4 0.4 0.4

5 0.5 0.5 0.5

6 0.8 0.8 0.8

7 1.0 1.0 1.0

8 2.0 2.0 2.0

9 3.0 3.0 3.0

10 4.0 4.0 4.0

11 5.0 5.0 5.0

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Drain Characteristics of MOSFET:

RESULT: The drain characteristics of a MOSFET are drawn.

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Exercise No.7 :(2 Hours):-

Aim: - To study the circuit of Colpitts or LC Oscillator & Determine the frequency of Oscillator.

Apparatus: - Colpitts oscillator trainer kit, CRO, Probes, connecting wires.

Circuit Diagram :-

Procedure:-

1. Study the circuit provided on the front panel of the kit.2. Connect CRO at O/P Vo terminal.3. Now switch ON the power supply note different voltages as per observation

table.4. Observe & note the frequency of oscillation & amplitude on CRO.

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5. Calculate the theoretical frequency of oscillation using formula.6. Compare theoretical & practical frequency of oscillation.7. Change the values of capacitor C2 & repeat above procedure.

Equation:-

??? ???√????

Where, ???? ??????????

Observations:-

1) With C2=56pf, observed frequency of oscillation FO = ------KHz2) With C2=100pf, observed frequency of oscillation FO = ------KHz

Result:- 1) With C2=56pf, frequency of oscillations is ------------KHz(Calculated) and ----- KHz(Observed)2) With C2=100pf, frequency of oscillations is ----------- KHz (Calculated) and ----- KHz (Observed)

Conclusion:- The tank circuit from by center tap capacitor C1 , C2 & inductor L provides feedback to transistor amplifier which produces a sine wave O/P in RF so Colpitts Oscillator is also called as RF Oscillator.

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Exercise No.8 :(2 Hours):-

Aim: - To study the circuit of RC Phase shift Oscillator & Determine the frequency of Oscillator.

Apparatus: - RC Phase shift oscillator trainer kit, CRO, Probes, connecting wires.

Circuit Diagram :-

Procedure:-

1. Study the circuit provided on the front panel of the kit.2. Connect CRO at O/P Vo terminal.3. Now switch ON the power supply note different voltages as per observation

table.4. Observe & note the frequency of oscillation & amplitude on CRO.

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5. Calculate the theoretical frequency of oscillation using formula.6. Compare theoretical & practical frequency of oscillation.7. Change RC network & repeat above procedure.

Equation:-

??? ?????√?? (Where N= No of RC networks)

As N=3

??? ???????

Observations:-

1) With network 1 observed frequency of oscillation FO = ------Hz2) With network 2 observed frequency of oscillation FO = ------Hz

Result:- 1) With network 1 frequency of oscillations is ------------ Hz(Calculated) and ----- Hz(Observed)2) With network 2 frequency of oscillations is ------------ Hz(Calculated) and ----- Hz(Observed)

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3.Quiz on the subject:-

Q:1 When a pn-junction is forward biased(a) electrons in the n region enter into the p region(b) holes in the p region enter into the n region(c) both a and b(d) none of these

Q:2 under normaloperating voltage , the reverse current in a silicon diode is about(a) 10mA(b) 1μA(c) 1000 μA(d) none of these

Q:3 The most commonly used transistor circuit arrangement is(a) CB(b) CE(c) CC(d) none of these

Q:4 The emitter of transistor is doped (a) heavily(b) lightly(c) moderately(d) none of these

Q:5 The biasing circuit which gives best stability to the Q point is (a) base resistor biasing(b) feedback resistor biasing(c) potential divider biasing(d) emitter resistor biasing

Q:6 The ideal value of stability factor is (a) 1

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(b) 5(c) 10(d) 100

Q:7 A practical constant current source should have internal resistance as(a) zero(b) low(c) high(d) none of these

4. Conduction of Viva-Voce Examinations:

Teacher should conduct oral exams of the students with full preparation. Normally, the objective questions with guess are to be avoided. To make it meaningful, the questions should be such that depth of the students in the subject is tested. Oral examinations are to be conducted in cordial environment amongst the teachers taking the examination. Teachers taking such examinations should not have ill thoughts about each other and courtesies should be offered to each other in case of difference of opinion, which should be critically suppressed in front of the students.

5. Evaluation and marking system:

Basic honesty in the evaluation and marking system is absolutely essential and in the process impartial nature of the evaluator is required in the examination system to become. It is a primary responsibility of the teacher to see that right students who are really putting up lot of hard work with right kind of intelligence are correctly awarded. The marking patterns should be justifiable to the students without any ambiguity and teacher should see that students are faced with just circumstances.