49198862 Final ECA Lab Manual

Department of ECE Electronic Circuit Analysis Laboratory

Vardhaman College of Engineering, Hyderabad

1. INTRODUCTION

1.1 PURPOSE OF THE LAB:

This manual has been prepared for use in the course Electronics & Communication

Engineering, Electronic Circuits Laboratory. The laboratory exercises are designed in such a

way as to reinforce the concepts taught in the lectures. Before performing the experiments,

the students must be aware of the basic safety rules for minimizing any potential dangers.

The specific objective of each experiment should be kept in mind throughout the laboratory

session. The conclusions based on the experiments and other observed phenomena must be

clearly discussed in the laboratory report.

1.2 PURPOSE OF THE PRELAB:

In each lab, you are given prelab questions. These are intended to help you prepare

for the lab. You should write your response in this manual. These questions are not handed

in, and they are not graded. If you do not understand a prelab question, be sure to ask your

Instructor.

2. CIRCUIT ANALYSIS USING PSPICE

PURPOSE

1. To learn the basic features of PSpice.

2. To use PSpice for the following:

i) Analysis by using Schematic Editor.

ii) Analysis by using Circuit File Editor.

INTRODUCTION TO SPICE

The rapid change in the field of electrical engineering is paralleled by programs that

use the computers increased capabilities in the solution of both traditional and novel

problems. With the availability of tools for computer-aided circuit analysis, circuits of great

complexity can be designed and analyzed within a shorter time and with less effort

compared to the traditional methods.

PSpice is a member of the SPICE (Simulation Program with Integrated Circuit

Emphasis) family of circuit simulators. In the following exercises you will use PSpice to solve

some circuits and to determine the quantities of interest.

Simulation Program with Integrated Circuit Emphasis (SPICE)

SPICE is a computer simulation and modeling program used by engineers to

mathematically predict the behavior of electronic circuits.

Developed at the University of California at Berkeley, SPICE can be used to simulate

circuits of almost all complexities. However, SPICE is generally used to predict the behavior

of low to mid frequency (DC to around 100MHz) circuits.

SPICE has the ability to simulate components ranging from the most basic passive

elements such as resistors and capacitors to sophisticated semiconductor devices such as

MESFETs and MOSFETs. Using these intrinsic components as the basic building blocks for

larger models, designers and chip manufacturers have been able to define a truly vast and

diverse number of SPICE models. Most commercially available simulators include more than

15,000 different components.



A circuit must be presented to SPICE in the form of a netlist. The netlist is a text

description of all circuit elements such as transistors and capacitors, and their corresponding

connections. Modern schematic capture and simulation tools such as Multisim allow users

to draw circuit schematics in a user-friendly environment, and automatically translate the

circuit diagrams into netlists. Both netlist and corresponding circuit schematic are presented

here in this manual, and some are left to the students to write on their own for practice.

Types Of Spice

The commercially supported versions of SPICE2 can be divided into two types: mainframe

versions and PC–based versions.

The mainframe versions are:

HSPICE, RAD-SPICE(Meta-Software)

IG-SPICE(A.B.Associates)

Precise(Electronic Engineering Software)

PSpice(Microsim)

AccuSim(Mentor Graphics)

Cadence-SPICE(Cadence Design)

SPICE-Plus(valid Logic)

The PC-versions are

AllSpice(Acotech)

IS-SPICE(Intusoft)

Z-SPICE(Z-Tech)

SPICE-Plus(Analog Design Tools)

DSPICE(Daisy Systems)

PSpice(Microsim)

Types of Analysis

Pspice allows various types of analysis. Each analysis is invoked by including its

command statement.

The types of analysis and their corresponding. (dot) commands are described below:

DC Analysis is used for circuits with time-invariant sources(e.g., steady-state dc

sources).

DC Analysis Commands:

• DC sweep of an input voltage/current source, a model parameter, or temperature

over a range of values (.DC)

• DC operating point to obtain all node voltages (.OP)

• Small-signal transfer function with small-signal gain, input resistance, and output

resistance (Thevenin’s equivalent) (.TF)

• DC small-signal sensitivities (.SENS)

Transient Analysis is used for circuits with time-variant sources (e.g., ac sources

and switched dc sources).

Transient Analysis Commands:

• Circuit behavior in response to time varying sources (.TRAN)

• DC and Fourier components of the transient analysis results (.FOUR)

AC Analysis is used for small-signal analysis of circuits with sources of variable

frequencies.

AC Analysis Commands:

• Circuit response over a range of source frequencies (.AC)

• Noise generation at an output node for every frequency (.NOISE)



Limitation Of Spice

As a circuit simulator, Pspice has the following limitations:

1. The student version of Pspice is restricted to circuits with 10 transistors only.

2. The program is not interactive; that is, the circuit cannot be analyzed for various

component values without editing the program statements.

3. Pspice does not support an iterative method of solution. If the elements of a circuit

are specified, the output can be predicted. On the other hand, if the output is

specified, Pspice cannot be used to synthesize the circuit elements.

4. The input impedance cannot be determined directly.

5. The PC version needs 512kilobytes of memory (RAM) to run.

6. Distortion analysis is not available in Pspice.

7. The output impedance of a circuit cannot be printed or plotted directly.

Circuit Descriptions

A circuit is described to a computer by using a file called the circuit file, which is

normally typed from a keyboard. The circuit file contains the circuit details of components

and elements, the information about the sources, and the commands for what to calculate

and what to provide as output.

The circuit file is the input to the SPICE program, which after executing the

commands, produces the results in another file called the output file.

A circuit must be specified in terms of element names, element values, nodes,

variable parameters, and sources.

The description and analysis of a circuit require specifications as follows:

• Element values

• Nodes

• Circuit elements

• Element models

• Sources

• Types of analysis

• Output variables

• PSpice output commands

• Format of circuit files

• Format of output files

Element Values: The element values are written in standard floating point notation with

optional scale and unit suffixes. Some values without suffixes that are allowable in PSpice

are

5 .5 5.0 5E+3 5.0E+3 5.E+3

There are two types of suffixes: the scale suffix and the unit suffix. The scale suffix

multiplies the number that it follows. The scale suffixes recognized by PSpice are

F = 1E-15

P = 1E-12

N = 1E-9

U = 1E-6

M = 1E-3

MIL = 25.4E-6

K = 1E3

MEG = 1E6

G = 1E9

T = 1E12



The unit suffixes that are normally used are

V=volt

A=amp

HZ=hertz

OHM=ohm(Ω)

H=henry

F=farad

DEG=degree

The first suffix always the scale suffix and the unit suffix follows the scale suffix. In the

absence of a scale suffix, the first suffix may be a unit suffix, provided it is not symbol of a

scale suffix.

Nodes: The location of an element is identified by the node numbers. Each element is

connected between two nodes. Node numbers are assigned to the circuit. Node 0 is

predefined as the ground. All nodes must be connected to at least two elements and should,

therefore, appear at least twice. Node numbers must be integers from 0 to 9999 for SPICE,

but need not be sequential.

Circuit Elements: Circuit elements are identified by names. A name must start with a

letter symbol corresponding to the element, but after it can contain either letters or

numbers. Names can be up to 8 characters long for SPICE2 and up to 131 characters long

for PSpice.

The format of describing passive elements is

<element name><positive node><negative node><value>

Where positive node current is assumed to flow into positive node N+ and out of negative

node N-. If the nodes are interchanged, the direction of the current through the element will

be reversed.

Sources:

The format for sources is

<source name><positive node><negative node><source model>

where the voltage of node N+ is specified with respect to node N-.

Voltage/Current Sources

EXP exponential pulse

FILE user data file

PULSE pulsed (single pulse or periodic waveform)

PWL piece-wise linear (table driven arbitrary waveform)

SFFM single frequency FM waveform

SIN sine wave

Sinusoidal Voltage Source:

This source generates a damped sinusoidal signal.

Transient spec syntax:

SIN (VO VA FREQ [TD] [THETA] [PHASE])

where items in [] are optional parameters.

Examples:

VSIG 3 0 SIN (-1V 2.5V 10MEG 1NS 1E10 90)

VAC in 0 SIN 0 120V 60Hz



Parameters Default Values Units

VO offset none V

VA amplitude none V

FREQ frequency 1/TSTOP Hz

TD delay 0.0 sec

THETA damping factor 0.0 1/sec

PHASE initial phase 0.0 degrees

The shape of the waveform is described by the following table:

Time Value

0 to TD VO

TD to TSTOP VO + VA * exp(-(time-TD)*THETA) * sin(2pi * FREQ * (time-TD)+PHASE)

Format Of Circuit Files

A circuit file that can be read by SPICE/PSpice may be divided into five parts:

i) The title, which describes the type of circuit or any comments;

ii) The circuit description, which defines the circuit elements and the set of model

parameters;

iii) The analysis description, which defines the type of analysis;

iv) The output description, which defines the way the output is to be presented; and

v) The end of the program (the .END command).

The format for a circuit file is as follows:

Title

Circuit description

Analysis description

Output description

.END (end-of-file statement)

Notes:

1. The first line is the title line, and it may contain any type of text.

2. The last line must be the .END command.

3. The order of the remaining lines is not important and does not affect the results of

simulations.

4. If a PSpice statement is more than one line, the statement can continue on the next

line. A continuation line is identified by a plus sign (+) in the first column of the next

line. The continuation lines must follow one another in the proper order.

5. A comment line may be included anywhere, preceded by an asterisk (*). Within a

statement, a comment is preceded by a semicolon (;), for PSpice only.

6. PSpice statement or comments can be in either upper- or lower case.

7. If you are not sure of any command or statement, the best thing is to run the circuit

file by using that command or statement and see what happens. SPICE/PSpice is

user-friendly software; it gives an error message in the output file that identifies a

problem.

Format Of Output Files

The results of simulation by SPICE/PSpice are stored in an output file. It is possible

to control the type and amount by various commands. If there is any error in the circuit file,

SPICE/PSpice will display a message on the screen indicating that there is an error and will

suggest looking at the output file for details. The output falls into four types:



1. A description of the circuit itself that includes the netlist, the device list, the model

parameter list, and so on.

2. Direct output from some of the analyses without the .PLOT and .PRINT commands.

This includes the output from .OP, .TF, .SENS, .NOISE, and .FOUR analyses.

3. Prints and plots by .PLOT and .PRINT commands. These include the output from the

.DC, .AC, and .TRAN analyses.

4. Run statistics. These include the various kinds of summary information about the

whole run, including times required by various analyses and the amount of memory

used.

Spice Models

BJT Models:

Statement syntax:

.MODEL <model name> <type> [(<parameter list>)]

where <type> is one of the following:

NPN npn BJT

PNP pnp BJT

NPN and PNP Model Parameters:

Name* Description Units Default

AF Flicker noise exponent - 1

BF Ideal maximum forward gain - 100

BR Ideal maximum reverse gain - 100

CJC B-C zero-bias depletion capacitance F 0

CJE B-E zero-bias depletion capacitance F 0

CJS Zero-bias collector-substrate capacitance F 0

EG Energy gap for temperature effect on IS eV 1.11

FC Forward bias depletion capacitance coeff. - 0.5

IKF Corner for forward gain high current roll-off A infinite

IKR Corner for reverse gain high current roll-off A infinite

IRB Current where base resistance falls half A infinite

way to its minimum value

IS Transport saturation current A 1E-16

ISC (C4) B-C leakage saturation current A 0

If >=1, specifies multiple of IS

ISE (C2) B-E leakage saturation current A 0

If >=1, specifies multiple of IS

ITF High-current parameter for effect on TF A 0

KF Flicker noise coefficient - 0

MJC B-C junction exponential factor - 0.33

MJE B-E junction exponential factor - 0.33

MJS Substrate junction exponential factor - 0

NC B-C leakage emission coefficient - 2

NE B-E leakage emission coefficient - 1.5

NF Forward current emission coefficient - 1

NR Reverse current emission coefficient - 1

PTF Excess phase at Freq=1/(TF*2) Hz degrees 0

RB Zero-bias base resistance Ohms 0

RBM Minimum base resistance at high currents Ohms RB



Name* Description Units Default

RC Collector resistance Ohms 0

RE Emitter resistance Ohms 0

TF Ideal forward transit time sec 0

TNOM Nominal model temperature deg. C 27

(TREF)

(T_MEASURED)

TR Ideal reverse transit time sec 0

TRB1 RB linear temperature coefficient - 0

TRB2 RB quadratic temperature coefficient - 0

TBC1 RC linear temperature coefficient - 0

TBC2 RC quadratic temperature coefficient - 0

TRE1 RE linear temperature coefficient - 0

TRE2 RE quadratic temperature coefficient - 0

TRM1 RBM linear temperature coefficient - 0

TRM2 RBM quadratic temperature coefficient - 0

VAF Forward Early voltage V infinite

VAR Reverse Early voltage V infinite

VJC B-C built-in potential V 0.75

VJE B-E built-in potential V 0.75

VJS Substrate junction built-in potential V 0.75

VTF Voltage describing VBC dependence of TF V infinite

XCJC Fraction of B-C depletion capacitance

connected to internal base node - 1

XTB Forward and reverse gain temperature

exponent - 0

XTF Coefficient for bias dependence of TF - 0

XTI Temperature exponent for effect on IS - 3

* Name in parenthesis is alias for parameter name.



3. PART – I SIMULATION USING PSPICE

Exp. No. 1: Common Emitter Amplifier

Exp. No. 2: Two stage RC coupled Amplifier

Exp. No. 3: Current Shunt Feedback Amplifier

Exp. No. 4: RC Phase Shift Oscillator

Exp. No. 5: Class A Power Amplifier

Exp. No. 6: Class B Complementary Symmetry Power Amplifier



Prelab:

1. Study the operation and working principle of CE amplifier.

2. Identify all the formulae you will need in this Lab.

3. Study the procedure of using Spice tool (Schematic & Circuit File).

4. In this lab you will use “decibels”, or dB. This is a dimensionless ratio, in logarithmic

form. The formula is XdB = 20log10(|X|), where X is any dimensionless ratio. For

example, X might be the gain A of an amplifier. If the gain A of an amplifier is 100,

you can also say that the amplifier has a gain of 40 dB. Note that negative values

correspond to a ratio of less than unity, for example an amplifier with a gain of 0.01

has a gain of -40 dB. You can compute a voltage ratio by taking the exponent of

10, for example the voltage ratio corresponding to a gain of 15 dB is 10(15/20) =

5.623. Calculate the following:

a. The gain in dB of an amplifier with a gain of 10,000.

b. The gain in dB of an amplifier with a gain of 0.1.

c. The voltage ratio that corresponds to – 3 dB.

Objective:

1. To simulate the Common Emitter amplifier in Pspice and study the transient and

frequency response.

2. To determine the phase relationship between the input and output voltages by

performing the transient analysis.

3. To determine the maximum gain, 3dB gain, lower and upper cutoff frequencies and

bandwidth of CE amplifier by performing the AC analysis.

Software Tool:

EdwinXP / Topspice / Multisim / Microsim / or any other equivalent tool.

Circuit Diagram:

PART – I EXPERIMENT NO. – 1

COMMON EMITTER AMPLIFIER



Circuit File:

*Title * Circuit file for CE Amplifier *Circuit description Q1 1 2 3 2n2222 RC 1 4 10k R1 2 4 47k R2 0 2 5k RS 5 6 500 RE 0 3 2k RL 0 7 10k C1 6 2 1u CE 0 3 10u C2 1 7 1u Vcc 4 0 12 Vs 5 0 AC 10m SIN 0 10m 1k .MODEL 2N2222 NPN(IS=2.56E-14 BF=200 NE=2 IKF=0.56 + BR= 5.00 NC= 2.00 ISE= 1.280E-11 + RB= 10.0 RC= .500 ISC= 1.280E-11 + CJE= 2.500E-11 TF= 5.333E-10 CJC= 8.000E-12 TR= 4.000E-08 KF=3E-16 + AF=1) *Analysis description .TRAN 1E-006 0.002 .AC DEC 10 10 1E+007 *Output description .PROBE *.END (end-of-file statement) .END

Theory:

The practical circuit of CE amplifier is shown in the figure. It consists of different

circuit components. The functions of these components are as follows:

1. Biasing Circuit: The resistances R1, R2 and RE form the voltage divider biasing

circuit for the CE amplifier. It sets the proper operating point for the CE amplifier.

2. Input capacitor C1: This capacitor couples the signal to the transistor. It blocks

any dc component present in the signal and passes only ac signal for amplification.

Because of this, biasing conditions are maintained constant.

3. Emitter Bypass Capacitor CE: An emitter bypass capacitor CE is connected in

parallel with the emitter resistance, RE to provide a low reactance path to the

amplified ac signal. If it is not inserted, the amplified ac signal passing through RE

will cause a voltage drop across it. This will reduce the output voltage, reducing the

gain of the amplifier.

4. Output Coupling Capacitor C2: The coupling capacitor C2 couples the output of

the amplifier to the load or to the next stage of the amplifier. It blocks dc and passes

only ac part of the amplified signal.

Operation: When positive half of the signal is applied, the voltage between base and

emitter (Vbe) is increased because it is already positive with respect to ground. So forward

bias is increased i.e., the base current is increased. Due to transistor action, the collector current IC is increased β times. When this current flows through RC, the drop IC RC increases

considerably. As a consequence of this, the voltage between collector and emitter (Vce)

decreases. In this way, amplified voltage appears across RC. Therefore the positive going

input signal appears as a negative going output signal i.e., there is a phase shift of 180°

between the input and output.



Procedure:

1. Schematic:

i) Select the components from the symbol library and place it on the

schematic window.

ii) The selected symbol is displayed on the screen in red. Move the symbol to

the desired location using the mouse.

iii) You can change the view of most symbols by performing the following

operations: rotate, mirror and flip.

iv) Wires and junctions are used to wire together parts and indicate electrical

connections.

v) To draw a wire, select the Wire menu command, Move the cursor to the

wire starting position and click the left mouse button or press Enter. Now

you can move the other end of wire to the desired location.

vi) The junction symbol (a large dot) indicates an electrical connection

between wires or between a wire and a part pin.

vii) Most parts (components) require that you specify the following set of

attributes: reference name, value or model name, and optional

parameters.

viii) You can also change the attributes by double-clicking on a part on the

schematic.

ix) Once circuit construction is completed; the analysis is to be performed.

x) To simulate a circuit, select the Analysis|Run Simulation menu command

from the Schematic.

xi) If there are any errors during the simulation, the simulator writes any

applicable error messages to the simulation output file.

xii) Three different modes of circuit analysis: DC, AC (frequency response)

and transient.

xiii) Before simulation, we have to do the analysis setup.

xiv) Once analysis setup is over, then perform Run Simulation.

xv) From the analysis note down the readings, plot the graph, do the

calculations.

2. Circuit File:

i) The SPICE circuit file (default filename extension ".CIR") is the input file

for the simulator program.

ii) This is a text file, which contains the circuit netlist, simulation command

and device model statements.

iii) Write the circuit file for the given schematic assuming the node numbers.

Save the circuit file.

iv) To simulate the circuit file, select the Analysis|Run Simulation menu

command from the circuit file menu.

v) If there are any errors during the simulation, the simulator writes any

applicable error messages to the simulation output file.

vi) Three different modes of circuit analysis: DC, AC (frequency response)

and transient.

vii) Before simulation, we have to do the analysis setup.

viii) Once analysis setup is over, then perform Run Simulation.

ix) From the analysis note down the readings, plot the graph, do the

calculations.



Observations/Graphs:

i) Transient Response:

ii) Frequency Response:

(Absolute gain Vs Frequency):



(Gain in dB Vs Frequency):

Inference:

1. From the transient analysis the phase relationship between input and output voltage

signals is ___________ degrees.

2. From the frequency response curve the following results are calculated:

S. No. Parameter Value

1 Max. Absolute Gain

2 Max. Gain in dB

3 3dB Gain

4 Lower Cutoff Frequency

5 Upper Cutoff Frequency

6 Bandwidth



Criticism:

1. Why the CE amplifier provides a phase reversal?

2. In the dc equivalent circuit of an amplifier, how are capacitors treated?

3. What is the effect of bypass capacitor on frequency response?

4. Define lower and upper cutoff frequencies for an amplifier.

5. State the reason for fall in gain at low and high frequencies.

6. What is meant by unity gain frequency?

7. Define Bel and Decibel.

8. What do we represent gain in decibels?

9. Why do you plot the frequency response curve on a semi-log paper?



WORKSPACE



Prelab:

1. Study the purpose of using multistage amplifiers.

2. Learn the different types of coupling methods.

3. Study the effect of cascading on Bandwidth.



Objective:

1. To simulate the Two Stage RC Coupled Amplifier in PSpice and study the transient

and frequency response.

2. To determine the phase relationship between the input and output voltages by

performing the transient analysis.


bandwidth of Two Stage RC Coupled Amplifier by performing the AC analysis.

4. To determine the effect of cascading on gain and bandwidth.

Software Tool:


Circuit Diagram:

Circuit File:

Left to the student to write on his/her own


TWO STAGE RC COUPLED AMPLIFIER



Theory:

An amplifier is the basic building block of most electronic systems. Just as one brick

does not make a house, a single-stage amplifier is not sufficient to build a practical

electronic system. The gain of the single stage is not sufficient for practical applications. The

voltage level of a signal can be raised to the desired level if we use more than one stage.

When a number of amplifier stages are used in succession (one after the other) it is called a

multistage amplifier or a cascade amplifier. Much higher gains can be obtained from the

multi-stage amplifiers.

In a multi-stage amplifier, the output of one stage makes the input of the next

stage. We must use a suitable coupling network between two stages so that a minimum loss

of voltage occurs when the signal passes through this network to the next stage. Also, the

dc voltage at the output of one stage should not be permitted to go to the input of the next.

If it does, the biasing conditions of the next stage are disturbed.

Figure shows how to couple two stages of amplifiers using RC coupling scheme. This

is the most widely used method. In this scheme, the signal developed across the collector

resistor RC of the first stage is coupled to the base of the second stage through the capacitor

CC. The coupling capacitor blocks the dc voltage of the first stage from reaching the base of

the second stage. In this way, the dc biasing of the next stage is not interfered with. For

this reason, the capacitor CC is also called a blocking capacitor.

As the number of stages increases, the gain increases and the bandwidth decreases.

RC coupling scheme finds applications in almost all audio small-signal amplifiers used

in record players, tape recorders, public-address systems, radio receivers, television

receivers, etc.

Procedure: Procedure is same as that of Experiment No. 1






(Gain in dB Vs Frequency)

(Comparing single stage and two stage amplifier response)



Inference:

1. From the transient analysis, it is observed that,___________________________

___________________________________________________________________.



1 Max. Gain in dB

2 3dB Gain



5 Bandwidth

3. From the AC response, it is observed that, _____________________________

__________________________________________________________________.

Criticism:

1. Why do you need more than one stage of amplifiers in practical circuits?

2. What is the effect of cascading on gain and bandwidth?

3. What happens to the 3dB frequencies if the number of stages of amplifiers

increases?

4. Why we use a logarithmic scale to denote voltage or power gains, instead of using

the simpler linear scale?

5. What is loading effect in multistage amplifiers?



WORKSPACE



Prelab:

1. Study the concept of feedback in amplifiers.

2. Study the characteristics of current shunt feedback amplifier.



Objective:

1. To simulate the Current Shunt Feedback Amplifier in PSpice and study the transient

and frequency response.


bandwidth of Current Shunt Feedback Amplifier by performing the AC analysis.

3. To determine the effect of feedback on gain and bandwidth.

Software Tool:


Circuit Diagram:

Circuit File:



CURRENT SHUNT FEEDBACK AMPLIFIER



Theory:

Feedback plays a very important role in electronic circuits and the basic parameters,

such as input impedance, output impedance, current and voltage gain and bandwidth, may

be altered considerably by the use of feedback for a given amplifier.

A portion of the output signal is taken from the output of the amplifier and is

combined with the normal input signal and thereby the feedback is accomplished.

There are two types of feedback. They are i) Positive feedback and ii) Negative

feedback. Negative feedback helps to increase the bandwidth, decrease gain, distortion, and

noise, modify input and output resistances as desired.

A current shunt feedback amplifier circuit is illustrated in the figure. It is called a

series-derived, shunt-fed feedback. The shunt connection at the input reduces the input

resistance and the series connection at the output increases the output resistance. This is a

true current amplifier.

Procedure:

Procedure is same as that of Experiment No. 1






Inference:



1 Max. Gain in dB

2 3dB Gain



5 Bandwidth

2. From the AC response, it is observed that, ______________________________

___________________________________________________________________.

Criticism:

1. State the merits and demerits of negative feedback in amplifiers.

2. If the bypass capacitor CE in an RC coupled amplifier becomes accidentally open

circuited, what happens to the gain of the amplifier? Explain.

3. When will a negative feedback amplifier circuit be unstable?

4. What is the parameter which does not change with feedback?

5. What type of feedback has been used in an emitter follower circuit?



WORKSPACE



Prelab:

1. Study the concept of positive feedback.

2. Study the operation and working principle of RC phase shift oscillator.



Objective:

1. To simulate the RC Phase Shift oscillator using PSpice and study the transient

response.

2. To determine the frequency of oscillation and compare its value with the theoretical

value.

Software Tool:


Circuit Diagram:

Circuit File:


Theory:

Any circuit which is used to generate an ac voltage without an ac input signal is

called an oscillator. Positive feedback is used in oscillators.

Based on the type of components used, the oscillators are classified in to two types.

They are LC oscillators and RC oscillators.

In the RC phase shift oscillator the required phase shift of 180° in the feedback loop

from output to input is obtained by using R and C components. Figure shows the circuit of

RC phase shift oscillator using cascaded connection of high pass filter. Here, a common

emitter amplifier is followed by three sections of RC phase shift network, the output of the

last section being returned to the input.


RC PHASE SHIFT OSCILLATOR USING TRANSISTORS



The phase shift, φ, given by each RC section is φ = tan-1

CRω1

. If R is made zero,

then φ will become 90°. But making R=0 is impracticable because if R is zero, then the

voltage across it will become zero. Therefore, in practice the value of R is adjusted such that

φ becomes 60°.

If the values of R and C are so chosen that, for the given frequency fr, the phase

shift of each RC section is 60°. Thus such a RC ladder network produces a total phase shift

of 180° between its input and output voltages for the given frequency. Therefore, at the

specific frequency fr, the total phase shift from the base of the transistor around the circuit

and back to the base will be exactly 360° or 0°, the thereby satisfying Barkhausen condition

for oscillation. The frequency of oscillation is given by

fr = 62

1

RCπ

At this frequency, it is found that the feedback factor of the network is |β| = 1/29. In order

that |Aβ| shall not be less than unity, it is required that the amplifier gain |A| must be more

than 29 for oscillator operation.

Procedure:



Transient Response:



Inference:

The theoretical and practical calculation of the frequency of oscillation of RC phase

shift oscillator is calculated as follows:

Theoretical

Calculations

Practical

Calculations

R = 10k

C = 0.01u

fr = kRC 462

1

+π

Where k = Rc/R = 0.18

fr = ________Hz

T= ________ms

f= 1/T= __________Hz

Criticism:

1. What is Barkhausen criterion?

2. What is the maximum phase shift provided by the single RC network?

3. What is the condition of phase shift oscillator to produce sustained oscillations?

4. Where does the starting voltage for an oscillator?

5. Why are RC oscillators preferred for the generation of low frequencies?

6. If the percentage feedback for sustained oscillations in an oscillator is 5%, what is

the required gain of amplifier?

7. Find the percentage feedback to produce sustained oscillators if amplifier gain is 60.

8. An RC phase shift oscillator circuit has 3 identical RC networks with R=100Ω,

C=10µF. Find the frequency of oscillation.



WORKSPACE



Prelab:

1. Study the difference between voltage and power amplifiers.

2. Study the operation and working principle of Class A power amplifier.

3. Identify all the formulas you will need in this Lab.


Objective:

1. To simulate the Class A power amplifier in PSpice and study the transient response.

2. To determine the Collector efficiency of Class A power amplifier.

Software Tool:


Circuit Diagram:

Circuit File:


Theory:

Class A power amplifier is one in which the output current flows during the entire

cycle (360°) of input signal. Thus the operating point is selected in such a way that the

transistor operates only over the linear region of its load line. So this amplifier can amplify

input signals of small amplitude.

The theoretical efficiency of transformer coupled or inductively coupled class A power

amplifier is 50%. Practically it is in the range of 30 – 35%. The formula for calculating

collector efficiency is % 100AC

DC

P

Pη = × , where PAC and PDC values are calculated as follows:


CLASS A POWER AMPLIFIER



Using RMS values:

PDC = VCC × IDC

PAC = Vrms×Irms

Using Peak values:

PDC = VCC × IDC

PAC = Vrms×Irms = 2

m mV I ,

2 2m m

rms rms

V IV I

= = Q

PAC =

2 2

2 2m m L

L

V I Ror

R

Using Peak to Peak values:

PDC = VCC × IDC

PAC = Vrms× Irms = 8

pp ppV I ,

2 2 2 2 2 2pp ppm m

rms rms

V IV IV I

= = = =

Q

PAC =

2 2

8 8pp pp L

L

V I Ror

R

Procedure:







Calculations:

PDC = VCC × IDC

PAC =

2 2

8 8pp pp L

L

V I Ror

R

% 100AC

DC

P

Pη = ×

Theoretical Efficiency = ___________________.

Practical Efficiency =___________________.

Inference:

1. From transient it is observed that the Class A power amplifier conducts for

____________ angle.

2. The collector efficiency of class A power amplifier is ______________.



Criticism:

1. Draw the block diagram of public address system.

2. Why a power amplifier is also known as a large signal amplifier?

3. What is need for power amplifier?

4. What is the difference between voltage amplifier and power amplifier?

5. Why voltage amplifier cannot work as power amplifier?

6. Why a power amplifier is always preceded by a voltage amplifier?

7. What is heat sink? Why it is used with power transistors?

8. What is collector efficiency?



WORKSPACE



Prelab:

1. Study the operation and working principle of Class B power amplifier.

2. Identify all the formulas you will need in this Lab.


Objective:

1. To simulate the Class B Complementary Symmetry power amplifier in PSpice and

study the transient response.

2. To eliminate the cross-over distortion using modified circuitry.

Software Tool:


Circuit Diagram:

Fig. Class B Complementary Symmetry Fig. Modified Class B Complementary

Symmetry Power Amplifier Power Amplifier

Circuit File: Left to the student to write on his/her own

Theory:

The use of both the input and output transformers in an ordinary push-pull amplifier

circuit is eliminated using a circuit called complementary-symmetry push-pull amplifier

circuit. This uses a pair of transistors having complementary symmetry, that is, one

transistor is PNP and the other is NPN.


CLASS B COMPLEMENTARY SYMMETRY POWER AMPLIFIER



Note that the complementary symmetry circuit requires two power supplies, since

each transistor must be biased suitably.

The transistors T1 and T2 are operated in class-B. That is, the bias is adjusted such

that the operating point corresponds to the cut-off points. Hence, with no signal input, both

transistors are cut-off and no collector current flows.

The signal applied at the input goes to the base of both the transistors. Since the

transistors are of opposite type, they conduct in opposite half-cycles of the input. For

example, during the positive half-cycle of the input signal, the PNP transistor T1 is reverse

biased and does not conduct. The NPN transistor T2, on the other hand, is forward-biased

and conducts. This results in a half-cycle of output voltage across the load resistor. The

other half-cycle of output across the load is provided by the conduction of transistor T1 (the

transistor T2 remains cut-off) during the negative half-cycle of the input. Since the collector

current from each transistor flows through the load during the alternate half-cycles of the

input signal, no centre-tapped output transformer is required.

The two transistors – though of opposite type – must be matched. If there is an

imbalance in the characteristics of the two transistors, even harmonics will no longer be

cancelled. This would result in considerable distortion. Increasing availability of

complementary transistors is making the use of class-B transformer coupled stages

obsolete. All modern power amplifier circuits are transformerless and use complementary

transistors.

Procedure: Procedure is same as that of Experiment No. 1


Transient Response:

Fig. Transient response of Class B Complementary Symmetry Power Amplifier



Fig. Transient response of Modified Class B Complementary Power Amplifier which

eliminates cross-over distortion

Inference:

1. From transient response of Class B complementary symmetry power amplifier, we

observe that _______________________________________________________.

2. Using modified circuitry, ______________________________________________.

Criticism:

1. What is cross-over distortion?

2. How to eliminate cross-over distortion?

3. What is harmonic distortion?

4. What is the maximum efficiency of class B Complementary Symmetry Power

amplifier?

5. What is the difference between Push-pull power amplifier and complementary

symmetry power amplifier?



WORKSPACE



4. PART – II TESTING USING HARDWARE LABORATORY

Exp. No. 1: Common Emitter Amplifier

Exp. No. 2: RC Phase Shift Oscillator using transistors

Exp. No. 3: Class B Complementary Symmetry Power Amplifier

Exp. No. 4: Single Tuned Voltage Amplifier

Exp. No. 5(a): Hartley Oscillator

Exp. No. 5(b): Colpitt’s Oscillator

Exp. No. 6: Class C Power Amplifier



Objective:

1. To plot the transient response waveforms and observe that the CE amplifier

produces a phase reversal.

2. To measure the maximum signal which can be amplified by the amplifier without

having clipped output.

3. To measure the voltage gain of the amplifier for different values of load

resistance.

4. To measure the voltage gain of the amplifier in the mid-frequency region.

5. To plot the frequency response curve and thus determine the lower and upper

cutoff frequencies, and Bandwidth of the amplifier.

Apparatus:

1. Transistor – 2n2222.

2. Resistors – 500, 2k, 5k, 10k (2), 47k.

3. Capacitors – 1u (2), 10u.

4. RPS – 12V.

5. Function Generator.

6. CRO.

7. Breadboard.

8. Connecting wires and Probes.

Circuit Diagram:

Fig. 2.1.1 Common Emitter Amplifier

PART – II EXPERIMENT NO. – 1

COMMON EMITTER AMPLIFIER



Theory:

In the amplifier circuit shown in the figure, the resistors R1, R2 and RE fix the

operating point. The resistor RE stabilizes it against temperature variations. The capacitor CE

bypasses the resistor RE for the ac signal. As it offers very low impedance path for ac, the

emitter terminal is almost at ground potential. When the ac signal is applied to the base, the

base-emitter voltage changes, because of which the base-current changes. Since collector

current depends upon the base current, the collector current also changes. When this

changing collector current passes through the load resistance RC, an ac voltage is produced

at the output. As the output voltage is much more than the input voltage, the circuit works

as an amplifier circuit. The voltage gain of this amplifier is given by the formula

AV = °∠

180

in

ac

r

Rβ

Where rin is the dynamic input resistance, β is the current amplification factor, and Rac is the

load resistance in the circuit.

Procedure:

1. Connect the circuit diagram as shown in the fig. 2.1.1.

2. Set Vs = 0 at 1 KHz.

3. Increase Vs till undistorted waveform is seen on the CRO.

4. Measure the input voltage Vs.

5. Vary the frequency from dc to 1MHz in convenient steps and measure the VO at

every frequency for constant input.

6. Find the voltage gain, AV =

S

O

V

V, AV(dB) = 20 log

S

O

V

V.

7. Plot AV Vs Frequency using Semi-log paper.

8. Repeat the above steps from 4 to 6 for different values of load resistance.

Expected Waveforms/Graphs:

1. Transient Response: 2. Frequency Response:

Fig. 2.1.2 (a) Transient Response (b) Frequency Response

t

Vout

t

Vin

f1 f2

Amax

Amax/√2

Gain

Freq.



Observations:

1. Voltage gain of the amplifier with variation in Load:

2. Voltage gain of the amplifier with variation in Frequency:

S. No. Input

Frequency (Hz)

Input Voltage,

Vin (mV)

Output Voltage,

Vout (V)

Absolute

Gain

Gain in

dB

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

S. No.

Load

Resistor,

RL(Ω)

Input Voltage,

Vin (mV)

Output Voltage,

Vout (V)

Absolute

Gain Gain in dB

1

2



Inference:

1. The phase relation between the input and output voltage waveforms is __________.

2. Maximum signal handling capacity of the amplifier (at 1kHz) is ____________mV.

3. The voltage gain _______________ as the load resistance _________________.

4. The absolute voltage gain of the amplifier in the mid frequency region is

___________.

5. The voltage gain in dB of the amplifier in the mid frequency region is

___________dB.

6. The lower cut-off frequency is ________Hz, and upper cut-off frequency is

_________Hz.

7. The Bandwidth of the amplifier is ____________Hz.

8. The gain bandwidth product is ______________Hz.



WORKSPACE



Objective:

To measure the frequency of oscillation of RC phase shift oscillator and compare with

that of the theoretical value.

Apparatus:


2. Resistors – 56K, 100K, 10K(5).

3. Capacitors – 10u(3), 0.01u(3)

4. RPS – 5V.

5. CRO.

6. Breadboard.


Circuit Diagram:

Procedure:

1. Connect the circuit on the breadboard as per the circuit diagram.

2. Connect the output of the circuit to the Channel 1 of the CRO using BNC Probe.

3. Note down the amplitude and time period of the output waveform.

4. Calculate the theoretical frequency of oscillations by using the formula

1

2 6rf

RCπ=

5. Calculate the practical frequency of oscillations.


RC PHASE SHIFT OSCILLATOR USING TRANSISTORS




Calculations:

Theoretical Frequency of Oscillations, 1

2 6rf

RCπ=

rf =

Observations:

Inference:

Frequency of the oscillations:

Time period T of the ac signal available at the output = _____________s.

Therefore, frequency 1

2 6rf

RCπ= Hz = ____________Hz.

t

Vout



WORKSPACE



Objective:

To observe the cross over distortion present in the Class B Complementary

Symmetry power amplifier.

Apparatus:

1. Transistors – 2n2222 (NPN) or SL100 (NPN), 2n2907A (PNP) or SK100 (PNP).

2. Resistor – 10K (1).

3. RPS – 12V.

4. CRO.

5. Breadboard.


Circuit Diagram:

Procedure:

1. Connect the circuit as shown in the figure.

2. Apply sinusoidal input voltage of 1V, 1 kHz to the circuit from the function generator

and observe it on the channel 1 of the CRO.

3. Connect the output to the channel 2 of the CRO.

4. Observe the cross over distortion in the output.


CLASS B COMPLEMENTARY SYMMETRY POWER AMPLIFIER




Inference:

From transient response of class B complementary symmetry power amplifier, we

observe that____________________________________________________________

______________________________________________________________________.

Vin

Vout

t

t



WORKSPACE



Prelab:

1. Study the concept of Resonance and Parallel Tuned Circuit.

2. Study the operation of Single Tuned Voltage Amplifiers.

Objective:

1. To measure the resonant frequency of a single tuned voltage amplifier.

2. To measure the gain at resonant frequency.

Apparatus:


2. Resistors – 100, 47K, 10K, 1K, 510.

3. Capacitors – 100n, 10u (2), 100u.

4. Inductor – 10mH.

5. RPS – 12V.

6. CRO.

7. Breadboard.


Circuit Diagram:

Theory:

A tuned amplifier uses one or more parallel tuned LC circuit as the load impedance.

Tuned amplifiers are used for amplifying electrical signals consisting of either a single radio

frequency (>30KHz) or a narrow band of frequencies in the RF (radio frequency) region.

Tuned amplifiers are properly referred to as radio frequency (RF) amplifiers.

The resonant frequency of tuned amplifier is given by rf = 1

2 LCπ


SINGLE TUNED VOLTAGE AMPLIFIER



Procedure:

1. Connect the circuit as per the circuit diagram.

2. Apply maximum undistorted input signal.

3. Vary the frequency conveniently and note down the output voltage.

4. Calculate the gain at resonant frequency.

5. Plot the curve between gain and resonant frequency.

6. Calculate the resonant frequency and compare it with the theoretical value.


Theoretical Calculations:

rf = 1

2 LCπ

= 3 9

1

2 10 10 100 10π − −× × ×

= 5.03 KHz

Practical Calculations:



Observations:

S. No. Input

Frequency (Hz)

Input Voltage,

Vin (mV)

Output Voltage,

Vout (V)

Absolute

Gain

Gain in

dB

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

Inference:

The resonant frequency of single tuned voltage amplifier is ______________________.

The maximum gain at resonant frequency is _______________________.

Criticism:

1. What is tuned amplifier?

2. Discuss the quality (Q) factor of a tuned amplifier, the factors that affect its value,

and its relationship to amplifier bandwidth.

3. How does tuned amplifier acts as a filter?

4. What is stagger tuning?

5. What is neutralization?



WORKSPACE



PreLab:

1. Study the operation and working principle of Hartley Oscillator.

2. Study the procedure for conducting the experiment in the lab.

Objectives:

To determine the frequency of oscillations of Hartley oscillator.

Apparatus:

1. Regulated power supply - 1 No.

2. CRO - 1 No.

3. Transistor (2N2222) - 1 No.

4. Resistors (100 KΩ, 10 KΩ,

1 KΩ, 100 Ω) - 1 No. each

5. Potentiometer (47 KΩ) - 1 No.

6. Capacitors (10 µf) - 3 Nos.

7. Capacitors (0.01 µf, 0.022 µf,

0.033 µf, 0.047 µf) - 1 No. each

8. Inductors (2 mH, 100 mH) - 1 No. each

9. Bread board - 1 No.

10. Connecting wires

Circuit Diagram:

Fig. Hartley oscillator

Theory: The Hartley Oscillator is shown in the fig. 15.1. The feedback network consisting of inductors L1, L2

and a capacitor C determines the frequency of oscillator. The frequency of Colpitt’s oscillator is given

by

( )1 2

1

2rf

L L Cπ=

+. The condition for sustained oscillations is

1

2fe

Lh

L= .

PART – II EXPERIMENT NO. – 5(a)

HARTLEY OSCILLATOR



Procedure:

1. Connect the circuit on the bread board as shown in fig 15.1 with C1.

2. Connect CRO at the output terminals of the circuit.

3. Adjust the potentiometer until undistorted sinusoidal output is observed on CRO.

4. Note down the amplitude and frequency of the output signal.

5. This frequency will be the frequency of oscillations of Hartley oscillator.

6. Repeat the above steps for different values of capacitors C2, C3, and C4.

Expected Graph:

Fig. 15.2 Output Waveform

Calculations: Frequency of oscillations, fO = 1

2 LCπ ,

where L = L1 + L2 and C = C1 or C2 or C3 or C4

Observations:

S.No. L1 (mH) L2 (mH) C (µf) fT (Hz) fP (Hz)

1 100 2 C1 = 0.01

2 100 2 C2 = 0.022

3 100 2 C3 = 0.033

4 100 2 C4 = 0.047

Where fT is theoretical frequency of oscillations

fP is practical frequency of oscillations

Inference:

Frequency of given Hartley oscillator is determined both practically and theoretically

Criticism:

1. What is the condition for sustained oscillations in Hartley oscillator?

2. In Hartley oscillator, which elements provide required dc bias to the transistor?

3. In Hartley oscillator, which elements determine the frequency of the output signal?

4. What are the advantages of Hartley over colpitt’s oscillator?

5. What is piezo electric effect?

6. Draw the ac equivalent circuit of a crystal.

7. What is the most frequently used material in crystal oscillator?

VO

t



Workspace



PreLab:

1. Study the operation and working principle of Colpitt’s Oscillator.


Objectives:

To determine the frequency of oscillations of Colpitt’s oscillator.

Apparatus:


2. CRO - 1 No.

3. Transistor (2N2222) - 1 No.

4. Resistors (1 KΩ, 1.5KΩ, 10 KΩ, 47 KΩ) - 1 No. each

5. Capacitors (100 µf, 0.1 µf, 0.01 µf) - 3 No.s

6. Inductors (5mH) - 1 No. each


8. Connecting wires

Circuit Diagram:

Fig. Colpitt’s Oscillator

Theory:

The Colpitt’s Oscillator is shown in the fig. 16.1. The feedback network consisting of capacitors C1, C2 and an inductor L determines the frequency of oscillator. The frequency of Colpitt’s oscillator is

given by 1 2

1 2

1

2r

C Cf

LC Cπ+= . The condition for sustained oscillations is

2

1fe

Ch

C= .

PART – II EXPERIMENT NO. – 5(b)

COLPITT’S OSCILLATOR



Procedure:

1. Connect the circuit on the bread board as shown in fig 16.1

2. Connect CRO at the output terminals of the circuit.

3. Note down the amplitude and frequency of the output signal.

4. This frequency will be the frequency of oscillations of Colpitt’s oscillator.

Expected Graph:

Calculations:

Frequency of oscillations, fO = 1

2 LCπ ,

where C = 1 2

1 2

C C

C C+

Observations:

Theoretical frequency of oscillations =

Practical frequency of oscillations =

Inference:

Frequency of given Colpitt’s oscillator is determined both practically and theoretically.

Criticism:

1. What is the condition for sustained oscillations in Colpitt’s oscillator?

2. In Colpitt’s oscillator, which elements provide required dc bias to the transistor?

3. In Colpitt’s oscillator, which elements determine the frequency of the output signal?

4. What are the applications of Colpitt’s oscillator?

5. What are the differences between Colpitt’s oscillator and Hartley oscillator?

VO

t



Workspace



PreLab:

1. Study the operation and working principle of Class C Power Amplifier.


Objectives:

To determine the efficiency of Class C Power Amplifier.

Apparatus:


2. CRO - 1 No.

3. Transistor - 1 No.

4. Resistors (560Ω, 10KΩ, 56Ω, 470Ω) - 1 No. each

5. Capacitors (100 µf-1, 0.1 µf-1, 22µf-2) - 4 Nos.

6. Inductors (2.5mH) - 1 No. each


8. Connecting wires

Circuit Diagram:


CLASS C POWER AMPLIFIER



Theory:

In a class C amplifier, the transistor is in the active region for less than half cycle. The

output current remains zero for more than half cycle. The DC current drawn from the power

supply is very small. In this operation, conduction takes place for less than one half cycle

(typically 120° to 150°). The resulting output current is non sinusoidal. The load is a tuned

circuit (parallel resonant circuit) which converts the non-sinusoidal output to nearly

sinusoidal form. Because of the flow of collector current less than 180°, the average

collector current is much less, and as a result the collector losses are still less so that the

efficiency is very high.

Class C amplifiers are mostly used in high frequency applications. And also this operation is

used with resonant or tuned circuits as for example, in radio and television transmitters

where efficiency is of atmost importance. The tuned circuit helps in rejecting harmonics that

are developed in the transistor due to its class C operation. The main application of a class

C operation is in communication.

In class C operation, collector current flows for less than one half cycle of the input signal,

as shown in figure 2-15 view D. The class C operation is achieved by reverse biasing the

emitter-base junction, which sets the dc operating point below cutoff and allows only the

portion of the input signal that overcomes the reverse bias to cause collector current flow.

The class C operated amplifier is used as a radio-frequency amplifier in transmitters.

Procedure:

1. Connect the circuit as shown in the figure.

2. Connect the input signal (say 15 to 18V).

3. By keeping input voltage constant, vary the frequency in regular steps.

4. Note down the corresponding output voltage from CRO for each frequency.

5. Plot the graph between gain (dB) and frequency.

6. Calculate bandwidth from the graph.

7. Calculate the resonant frequency using 1

2 LCπ

8. To calculate efficiency fix the input frequency at resonant frequency.

9. By varying the input voltage observe the maximum distortionless waveform.

10. At that point noted down the ammeter reading and output voltage from CRO.

11. Calculate the DC input power using Pdc =VCC IC.

12. Calculate the AC output power using Pac =

2 2

8 8pp pp L

L

V I Ror

R.

13. Calculate the efficiency η =( Pac/ Pdc)x 100



Expected Graph:

Observations:

S. No. Input

Frequency (Hz)

Input Voltage,

Vin (mV)

Output Voltage,

Vout (V)

Absolute

Gain

Gain in

dB

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

f1 f2

Amax

Amax/√2

Gain

Freq.



Calculations:

Resonant frequency:

PDC=

PAC=

Efficiency =

Inference:



WORKSPACE



5. PART – III EXTRA EXPERIMENTS/EXERCISES

FOR PRACTICE IN PSPICE

Exp. No. 1: Thevenin’s Analysis

Exp. No. 2: Series RLC circuit

Exp. No. 3: Darlington Pair Amplifier

Exp. No. 4: Cascode Amplifier



Exercise – 1:

A DC Circuit is shown in the figure. Use PSpice to calculate and print (a) the voltage

gain Av = V(2,4)/Vin, (b) the input resistance Rin = Vin/Iin , (c) Thevenin’s (output) resistance

Rout=RTh between nodes 2 and 4, and (d) Thevenin’s voltage VTh between nodes 2 and 4.

Exercise – 2:

A pulse input is applied to the RLC circuit as shown in the figure. Use PSPICE to

calculate and plot the transient response from 0 to 400us with a time increment of 1us. The

capacitor volyage V(3) and the current through R1 i.e., I(R1) are to be plotted.



Exercise – 3:

A bipolar Darlington pair amplifier is shown in figure. Calculate and print the voltage gain,

the input resistance, and the output resistance. The input voltage is 5V.



Exercise – 4:

A cascade amplifier circuit is shown in the figure below. Perform the experiment to plot the

transient and frequency responses using SPICE schematic and circuit file editors.



WORKSPACE



Workspace

49198862 Final ECA Lab Manual

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Transcript of 49198862 Final ECA Lab Manual