Dept. of Electronics & Communication Engg.

INDUR
INSTITUTE OF ENGINEERING & TECHNOLOGY
SIDDIPET DIST. – 502277

LABORATORY MANUAL

Network Analysis Lab

2rd Year 3rd Sem. DECE
(As per C-21 Academic Regulation)

Prepared and verified by

K KIRANMAI

DEPARTMENT
OF
ELECTRONICS AND COMMUNICATION ENGINEERING

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PREFACE
Almost all Electronic circuits must include means for amplifying electrical signals and

power supplies. This lab course is to gain the practical hands on experience by exposing the

students to applications network theorems, Resonance & filters and their characteristics.

Students are made familiar with Network analysis as well as measuring all electrical

quantity of analog circuits. Students are made to design the application circuitry by utilizing the

basic analog circuits. This would enable them to choose the appropriate IC for required

application.

Course Objectives:

Analyze and design various Network theorems.

Analyzing and measuring waveforms using Electronic measuring equipment

Analyzing and measuring waveform using CRO.

Analyze and design various Pulse and wave shaping circuits

Design Resonance & constant K filters of 1st order circuits .

Prerequisite:
1. The students already studied the subjects of EDC . So they will be having
theoretical knowledge about the Experiments.
2. Mean while NA practical Lab also they have studying in the present semester.
3. Hence they will be having some of the knowledge regarding the Experiments.
In the current semester they will improve their skills by doing the experiments

Course Outcome:

They Understand and implement the concepts of network theorems and analysis of
basic electronic circuits.

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LAB CODE

1. Students should report to the concerned labs as per the time table schedule.

2. Students who turn up late to the labs will in no case be permitted to perform the
experiment scheduled for the day.

3. After completion of the experiment, certification of the concerned staff in-charge in the
observation book is necessary.

4. Staff member in-charge shall award marks based on continuous evaluation for each
experiment out of maximum 10 marks and should be entered in the notebook

5. Students should bring a note book of about 100 pages and should enter the
readings/observations into the note book while performing the experiment.

6. The record of observations along with the detailed experimental procedure of the
experiment performed in the immediate last session should be submitted and certified by
the staff member in-charge.

7. Not more than three students in a group are permitted to perform the experiment on a
setup.

8. The group-wise division made in the beginning should be adhered to, and no mix up
of student among different groups will be permitted later.

9. The components required pertaining to the experiment should be collected from stores
in-charge after duly filling in the requisition form.

10. When the experiment is completed, students should disconnect the setup made by them,
and should return all the components/instruments taken for the purpose.

11. Any damage of the equipment or burn-out of components will be viewed seriously
either by putting penalty or by dismissing the total group of students from the lab for the
semester/year.

12. Students should be present in the labs for the total scheduled duration.

13. Students are required to prepare thoroughly to perform the experiment before coming to
Laboratory.

14. Procedure sheets/data sheets provided to the students’ groups should be maintained
neatly and to be returned after the experiment.

Before leaving the lab

 Place the chairs properly.

 Please check the laboratory notice board regularly for updates.

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LIST OF EXPERIMENTS
S.NO EXPERIMENT NAME PG NO
1. 1. Verify Thevenin’s theorem for a given network. 6
2. 2. Verify Nortorn,s theorem for a given network. 10
3. 3. Verify Maximun power transfer theorem for a given network. 13
4. 4. Verify superposition theorem for a given network. 18
5. 5. Using a digital LCR meter measure the values of given resistances, 22
capacitances and inductor and the quality factor of a coil.
6. 6. Using a CRO find out the amplitude and frequency values of a given 27
waveform derived from a AF /RF generating instrument.
7. 7. Observe the charge and discharge curves of using a digital CRO, 30
determine the time constant of a given RC circuit.
8. 8. Measure the Rise time, Fall time, duty cycle, Pulse width, Pulse 41
amplitude, overshoot of a given Pulse on CRO.
9. 9. Observe and sketch the waveform of a given RC differentiator network 46
being driven by a pulse (pulse width t d) under the following conditions. 1)
RC>> t d 2) RC<< td 3) RC=td
10. 10. Observe and sketch the waveform of a given RC integrator network 49
being driven by a pulse (pulse width td) under the following conditions of
time constants. 1) RC>> t d 2) RC<< t d 3)RC=td .
11. 11. Demonstrate the use of integrator circuit for producing triangular wave / 54
Ramp through a square wave using a CRO.
12. 12. Design a Low pass filter using a given Integrator circuit (RC) for a given 57
cut off frequency say 1KHz.
13. 13. Design a Low pass filter using a given Integrator circuit (RC) for a given 60
cut off frequency say 2KHz.
14. 14. Realize a series clipper and observe the waveform on a CRO. 63
15. 15. Realize a parallel clipper and observe the waveform on a CRO. 66

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16. 16. Realize a positive clipper without bias and observe the waveform on 68
a CRO.
17. 17. Realize a positive clipper with bias and observe the waveform on a 70
CRO.
18. 18. Realize a negative clipper without bias and observe the waveform on 73
a CRO.
19. 19. Realize a negative clipper with bias and observe the waveform on a 75
CRO.
20. 20. Realize a zener diode clipper and observe the wave form on a CRO. 78
21. 21. Realize a Clamper circuit and observe the input and output 81
waveforms on CRO.
22. 22. Plot the resonance curve of a given series tuned circuit. 85
23. 23. Plot the resonance curve of a given parallel tuned circuit. 88

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Experiment No. 1 Verify Thevenin’s theorem for a given network.

Date :

I AIM:
To verify Thevenin’s theorem and to find the full load current for the given circuit.
Determine the Thevenin’s resistance of a potential divider network.
II. i. TOOLS/ EQUIPMENTS/APPARATUS REQUIRED

S.No. Apparatus Range Quantity

1 RPS (regulated power supply) (0-30V) 2
2 Ammeter (0-10mA) 1
3 Resistors 220Ω, 330Ω,470Ω 1 each
4 Bread Board -- Required
5 DRB -- 1

III THEORY
Statement: Thevenin's theorem for linear electrical networks states that any combination of
voltage sources, current sources and resistors with two terminals is electrically equivalent to a
single voltage source V and a single series resistor RTh. ... RTh equals VTh divided by IAB.

Thevenin’s Theorem can be used for two purposes

1. To calculate the current through (or voltage across) a component in any circuit,
or
2. To develop a constant voltage equivalent circuit which may be used to simplify the
analysis of a complex circuit?
Any linear one-port network can be “replaced with” a single voltage source in series with a
single resistor (see Figure 1 below). The voltage source is called the Thevenin equivalent
voltage, and the resistor is called the Thevenin equivalent resistance. What this means is that a
single voltage source and series resistor will behave identically to the actual part of the circuit it
is replacing.
IV CIRCUIT DIAGRAM
In this experiment, you will use Thevenin’s theorem to solve a complex DC circuit.

Figure 1 A network replaced with its Thevenin equivalent circuit

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V PROCEDURE:
1. Connections are given as per the circuit diagram.
2. Set a particular value of voltage using RPS and note down the corresponding ammeter
readings.
The steps used for Thevenin’s Theorem are listed below
To find VTH
3. Remove the load resistance and measure the open circuit voltage using multimeter
(VTH).
To find RTH
4. To find the Thevenin’s resistance, remove the RPS and short circuit it and find the
RTH using multimeter.
5. Give the connections for equivalent circuit and set V TH and RTH and note the
corresponding ammeter reading.
6. Verify Thevenins theorem.
VI OBSERVATIONS

VII. CALCULATIONS
Step 1
Remove the resistor (R) through which you wish to calculate the current or across which you
want to know the voltage. Label these terminals (where the resistor was removed) “a” and “b”.
Calculate the voltage across these open terminals. This is called the open circuit voltage or the
Thevenin equivalent voltage, VTH.

+
VTH
−

Step 2
From the open terminals, (“a” and “b”) calculate the resistance “looking back” from the open
terminals with all voltage sources removed and replaced by their internal resistances (if R Internal =
0, replace the voltage source with a short). This resistance is RTH.

RTH

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Now we have the components we need to create the Thevenin equivalent circuit as shown
below using the Thevenin equivalent voltage and resistance values calculated above connected

in series with the load resistor as shown below.

Step 3
The current (through R) you wish to calculate will be:

and the voltage across R will be:

where: VTH is from Thevenin equivalent voltage obtained in Step 1, RTH is the Thevenin
equivalent voltage obtained in Step 2, and R is the value of the resistor removed in Step 1.
VIII. NATURE OF GRAPH
c) If there are both independent and dependent sources, then compute (i) RTh = VTest/ Itest (all
independent sources set equal to zero) (ii) compute RTh from VOC/ ISC

IX. INFERENCE
Assuming all passive component working ideal condition and t=0 all initial condition assume
zero.

X. PRECAUTIONS
1 Voltage control knob of RPS should be kept at minimum position.
2 Current control knob of RPS should be kept at maximum position
3 Avoid making loose connections.
4 Reading should be taken carefully without parallax error.
5 Avoid series connection of voltmeters and parallel connection of ammeters.

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XI. TROUBLE SHOOTING:

1. Check the Multimeter
2. Check the battery connections .Measure V and I with the DMM..
XII RESULTS / CONCLUSIONS
Hence the Thevenin’s theorem is verified both practically and theoretically
Theoretical and Practical Values
E(V) VTH(V) RTH(Ω) IL (mA)
Circuit - I Equivalent
Circuit
Theoretical 10 5 495 3.34 3.34

Practical

XIII EXTENSION
Thevenin-Norton Equivalencies
XIV APPLICATIONS
Application
1.Thevenin’s Theorem is very useful to reduce a network with several voltage sources and
resistors to an equivalent circuit composed a single voltage source and a single resistance
connected to a load only.
2. It is used in simplifying and analyzing complex linear networks power systems and circuits
where one particular where a particular load resistor, RL in the circuit is subject to change, and
recalculation of the circuit is necessary with each trial value of load resistance to determine
voltage across it and current through it. This show that Thevenin’s theorem is important to
apply in analyzing DC circuits so that we no need to analyze the circuits all over again when got
a variable load. Source modeling is also important application of Thevenin’s Theorem. An
active source such as a battery is often characterized by its Thevenin equivalent circuit
3. It is used in resistance measurement using the Wheatstone bridge provides an example of the
usefulness of the Thevenin’s Theorem too. The bridge circuit is able to simplify to an equivalent
circuit from the load resistor by using the Thevenin’s theorem. It makes us easy to measure an
unknown resistance in the complicated Wheatstone Bridge...
XV QUESTIONS
1. What is meant by the word "equivalent" in Thevenin Equivalent circuits?

2. What is the practical value of Thevenin Equivalent circuits? Give several practical
applications in which Thevenin Equivalent circuits are used.

3. For the following circuit, use Thevenin’s theorem to find the current through R.
Show the Thevenin equivalent circuit you used and the values of Rth and Vth you
obtained.

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Experiment No. 2 Verify Norton’s theorem for a given network.

Date :
I AIM: To verify Norton’s theorem for the given circuit.
II EQUIPMENTS/APPARATUS/COMPONENTS REQUIRED
Apparatus Required:
Sl.No. Apparatus Range Quantity
1 RPS (regulated power supply) (0-30V) 2
2 Ammeter (0-10mA) 1
3 Resistors 1KΩ, 330Ω 3,1
4 Bread Board -- Required
5 DRB -- 1
III THEORY
Norton's theorem states that a network consists of several voltage sources, current sources and
resistors with two terminals, is electrically equivalent to an ideal current source " I N" and a
single parallel resistor, RN. The theorem can be applied to both A.C and D.C cases. The Norton
equivalent of a circuit consists of an ideal current source in parallel with an ideal impedance (or
resistor for non-reactive circuits).

The Norton equivalent circuit is a current source with current "IN" in parallel with a resistance
RN. To find its Norton equivalent circuit,
1. Find the Norton current "IN". Calculate the output current, "I AB", when a short circuit is
the load (meaning 0 resistances between A and B). This is IN.
2. Find the Norton resistance RN. When there are no dependent sources (i.e., all current and
voltage sources are independent), there are two methods of determining the Norton impedance
RN. Calculate the output voltage, VAB, when in open circuit condition (i.e., no load resistor
meaning infinite load resistance). RN equals this VAB divided by IN.
or Replace independent voltage sources with short circuits and independent current sources with
open circuits. The total resistance across the output port is the Norton impedance R N.
However, when there are dependent sources the more general method must be used. This
method is not shown below in the diagrams.
Connect a constant current source at the output terminals of the circuit with a value of 1
Ampere and calculate the voltage at its terminals. The quotient of this voltage divided by the 1
A current is the Norton impedance RN. This method must be used if the circuit contains
dependent sources, but it can be used in all cases even when there are no dependent sources.
IV CIRCUIT DIAGRAM

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V PROCEDURE
1. Connections are given as per circuit diagram.
2. Set a particular value in RPS and note down the ammeter readings in the original
circuit.
To Find IN:
3. Remove the load resistance and short circuit the terminals.
4. For the same RPS voltage note down the ammeter readings.
To Find RN:
5. Remove RPS and short circuit the terminal and remove the load and note down
the resistance across the two terminals.
Equivalent Circuit:
6. Set IN and RN and note down the ammeter readings.
7. Verify Norton’s theorem.

VI OBSERVATIONS

SR Vdc Measured Value Theoretical value

IN RN IN RN

VII. CALCULATIONS
To find load current in circuit 1:

To find IN

To find RN

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VIII. NATURE OF GRAPH

Norton’s equivalent circuit

IX. INFERENCE
Assuming all passive component working ideal condition and t=0 all initial condition assume
zero.

X. PRECAUTIONS
1 Voltage control knob of RPS should be kept at minimum position.
2 Current control knob of RPS should be kept at maximum position
3 Avoid making loose connections.
4 Reading should be taken carefully without parallax error.
5 Avoid series connection of voltmeters and parallel connection of ammeters.

XI. TROUBLE SHOOTING:

1. Check the Multimeter

2. Check the battery connections .Measure V and I with the DMM..

XII RESULTS / CONCLUSIONS

Hence the Norton’s theorem is verified both practically and theoretically

XIII EXTENSION
Thevenin-Norton Equivalencies

XIV APPLICATIONS
1. Norton theorem are useful for electrical calculations. They offer a quite interesting way to
simplify circuit diagrams allowing to reach partial solutions in the selected zones to be
analyzed. For example: Their application allows for the fault currents calculation in a point
provided that the equivalent Thévenin or Norton are known. Norton is thee most used theorem
in all of circuit design.
2. It reduces any circuit, no matter how complex, to a real generator, with it's characteristic
internal impedance. It is used to determine how different loads will effect a signal source
output.
3. It is used in transmission line drive calculations.
4. It is used to determine how long it will take a digital signal to go down a bus or a
backplane. Learn it, and keep it in the front of your forehead.

XV QUESTIONS
1. State Norton's Theorem as applicable to D.C. network.
2. What is the difference between Thevenin's Theorem and Norton's Theorem?

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Experiment No. 3 Verify Maximum Power transfer theorem

Date :

I AIM: To verify Maximum Power transfer theorem for the given circuit.
II EQUIPMENTS/APPARATUS/COMPONENTS REQUIRED

III THEORY

Statement:

In a linear, bilateral circuit the maximum power will be transferred to the load when load
resistance is equal to source resistance. According to the maximum power transfer theorem, a
load will receive maximum power from a source when its resistance (RL) is equal to the internal
resistance (RI) of the source. If the source circuit is already in the form of a Thevenin or Norton
equivalent circuit (a voltage or current source with an internal resistance), then the solution is
simple. If the circuit is not in the form of a Thevenin or Norton equivalent circuit, we must first
use Thevenin’s or Norton’s theorem to obtain the equivalent circuit.

IV CIRCUIT DIAGRAM
Circuit – 1

To find VTH

To find RTH

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Thevenin’s Equation Circuit

V PROCEDURE

Procedure:
Circuit – I
1. Connections are given as per the diagram and set a particular voltage in RPS.
2. Vary RL and note down the corresponding ammeter and voltmeter reading.
3. Repeat the procedure for different values of RL & Tabulate it.
4. Calculate the power for each value of RL.

To find VTH:
5. Remove the load, and determine the open circuit voltage using multimeter (VTH)

To find RTH:
6. Remove the load and short circuit the voltage source (RPS).
7. Find the looking back resistance (RTH) using multimeter.

Equivalent Circuit:
8. Set VTH using RPS and RTH using DRB and note down the ammeter reading.
9. Calculate the power delivered to the load (RL = RTH)
10. Verify maximum transfer theorem.

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VI OBSERVATIONS

VII. CALCULATIONS

Here’s how to arrange for the maximum power transfer.

1. Find the internal resistance, RI. This is the resistance one finds by looking back into the two
load terminals of the source with no load connected. As we have shown in the Thevenin’s
Theorem and Norton’s Theorem chapters, the easiest method is to replace voltage sources by
short circuits and current sources by open circuits, then find the total resistance between the two
load terminals.

2. Find the open circuit voltage (UT) or the short circuit current (IN) of the source between the
two load terminals, with no load connected.

Once we have found RI, we know the optimal load resistance

(RLopt = RI). Finally, the maximum power can be found

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In addition to the maximum power, we might want to know another important quantity:
the efficiency. Efficiency is defined by the ratio of the power received by the load to the total
power supplied by the source. For the Thevenin equivalent:

and for the Norton equivalent:

(B) Repeat calculation for Connect 4 ohms speaker to obtain 4 ohms impendence and test for
maximum power output by audio amplifier at 4 ohms output terminals

VIII. NATURE OF GRAPH

IX. INFERENCE
Assuming all passive component working ideal condition and t=0 all initial condition assume
zero.

X. PRECAUTIONS
1. Voltage control knob of RPS should be kept at minimum position.
2. Current control knob of RPS should be kept at maximum position
3. Avoid making loose connections.
4. Reading should be taken carefully without parallax error.
5. Avoid series connection of voltmeters and parallel connection of ammeters.

XI. TROUBLE SHOOTING

1. Check the Multimeter
2. Check the battery connections .Measure V and I with the DMM..
XII RESULTS / CONCLUSIONS
Hence the maximum power transfer theorem is verified both practically and theoretically
XIII EXTENSION

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Obtain relation between maximum power transfer theorem and Thevenin-Norton

Equivalencies

XIV APPLICATION
1. Maximum Power Transfer Theorem is applicable to analyze the circuit in different
electrical engineering fields.
2. It is widely useful to analyze the electronic and communication network.
3. It is frequently significant in the operation of transmission line and antenna. Its use in
electrical Power transmission and distribution system is limited.

XV QUESTIONS:
Viva questions:

1. State maximum power transfer theorem?

2. Give the expression for maximum power?
3. What is the condition for maximum power?
4. Give the 3 different equations of power?
5. What is the unit for power?

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Experiment No. 4 Verify Super position theorem for a given network.

Date :

I AIM : Verify superposition theorem

II EQUIPMENTS/APPARATUS/COMPONENTS REQUIRE

III THEORY

SUPERPOSITION THEOREM STATEMENT

In any linear bilateral network containing two or more energy sources the response at any
element is equal to the algebraic sum of the responses caused by the individual sources. i.e. while
considering the effect of individual sources, the other ideal voltage sources and ideal current sources in
the network are replaced by short circuit and open circuit across the terminals. This theorem is valid only
for linear systems
IV CIRCUIT DIAGRAM

V Procedure:
1. Give the connections as per the diagram.
2. Set a particular voltage value using RPS1 and RPS2 & note down the ammeter reading
3. Set the same voltage in circuit I using RPS1 alone and short circuit the terminals
and note the ammeter reading.
4. Set the same voltage in RPS2 alone as in circuit I and note down the ammeter reading.
5. Verify superposition theorem.

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VI OBSERVATIONS

VII. CALCULATIONS

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VIII. NATURE OF GRAPH

IX. INFERENCE
Assuming all passive component working ideal condition and t=0 all initial condition assume zero.
X. PRECAUTIONS
1. All the connections must be made properly.
2. All the readings must be taken without an parallax error.
3. The current should not exceed the rated value.
4. Voltage control knob of RPS should be kept at minimum position.
5. Current control knob of RPS should be kept at maximum position
6. Avoid making loose connections.
7. Reading should be taken carefully without parallax error.
8 Avoid series connection of voltmeters and parallel connection of ammeters.

XI. TROUBLE SHOOTING:

1. Check the Multimeter
2. Check the battery connections .
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3. Measure V and I with the DMM

XII RESULTS
Superposition theorem have been verified theoretically and practically.
XIII EXTENSION
Make relation between Super position theorem and Thevenin’s theorem
XIV APPLICATIONS
The superposition principle applies to many areas of physics, but basically, it's a way to combine the
electric fields of many charges together to make up a more complicated electric field.
2. It is a great theorem because it makes things simpler instead of more complicated. How often does that
happen! You can see the superposition principle in action when you watch multiple rain drops in a lake, or
listen to multiple voices in a room. In the case of rain on a lake, the ripples all go through each other; you
can see many separate, circular ripples in the pond. Likewise, all the voices of people talking in a room can
be heard at the same time. You can usually pay attention to only one, but any person you listen to will
come through clearly. The sound waves do not run into each other.
3. The superposition principle applies to things we can't see, like electric fields.

XVI VIVA QUESTIONS:

1. What is superposition theorem?
2. What is reciprocity theorem?
3. What is done to voltage sources while applying superposition theorem?
4. What is done to current sources while applying superposition theorem?
5. What is bilateral circuit?

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Using a digital LCR meter measure the values of given

resistances, capacitances and inductors and the quality factor of
No. 5 a coil
Date :

I AIM: Experiment
Use the DIGITAL LCR meter to measure Resistance ,Inductance, Capacitance and Q
II EQUIPMENTS/APPARATUS/COMPONENTS REQUIRE
LCR Meter, Resistors, inductors, capacitors.
III THEORY

An LCR meter is a type of electronic test equipment used to measure the inductance (L), capacitance (C),
and resistance (R) of an electronic component[1]. In the simpler versions of this instrument the impedance
was measured internally and converted for display to the corresponding capacitance or inductance value.
Readings should be reasonably accurate if the capacitor or inductor device under test does not have a
significant resistive component of impedance. More advanced designs measure true inductance or
capacitance, as well as the equivalent series resistance of capacitors and the Q factor of inductive
components. n general versions of LCR meter, these quantities are not measured directly, but determined
from a measurement of impedance. The necessary calculations are, however, incorporated in the
instrument's circuitry; the meter reads L, C and R directly with no human calculation required. Electrical
impedance, or simply impedance, describes a measure of opposition to alternating current (AC). With the
help of LCD meter, it is possible to measure an object's resistance to steady electrical current. It will
determine the relative change in magnitude of the repetitive variations of the voltage and current known as
amplitudes.

IV CIRCUIT DIAGRAM
components are modeled with one of the two following equivalent circuits

where X is the reactance of the component, Rs is the series resistance, and Rp is the parallel resistance. If
the reactance is large, the series resistance may be
negligible, so the parallel model might be a better fit. Conversely, if the reactance is small, the parallel
resistance may be negligible, so you may want to use the series model. Thus, the guideline would be to
tend to use the parallel circuit model for small capacitors and
the series model for large capacitors

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V PROCEDURE

Usually the device under test (DUT) is subjected to an AC voltage source. The meter measures the voltage
across and the current through the DUT. From the ratio of these the meter can determine the magnitude of
the impedance. The phase angle between the voltage and current is also measured in more advanced
instruments; in combination with the impedance, the equivalent capacitance or inductance, and resistance,
of the DUT can be calculated and displayed. The meter must assume either a parallel or a series model for
these two elements. An ideal capacitor has no characteristics other than capacitance, but there are no
physical ideal capacitors. All real capacitors have a little inductance, a little resistance, and some defects
causing inefficiency. These can be seen as inductance or resistance in series with the ideal capacitor or in
parallel with it. And so likewise with inductors. Even resistors can have inductance (especially if they are
wire wound types) and capacitance as a consequence of the way they are constructed. The most useful
assumption, and the one usually adopted, is that LR measurements have the elements in series (as is
necessarily the case in an inductor's coil) and that CR measurements have the elements in parallel (as is
necessarily the case between a capacitor's 'plates'). Leakage is a special case in capacitors, as the leakage is
necessarily across the capacitor plates, that is, in series.

An LCR meter can also be used to measure the inductance variation with respect to the rotor position in
permanent magnet machines. (However, care must be taken, as some LCR meters will be damaged by the
generated EMF produced by turning the rotor of a permanent-magnet motor; in particular those intended
for electronic component measurements.)

Handhold LCR meters typically have selectable test frequencies of 100 Hz, 120 Hz, 1 kHz, 10 kHz, and
100 kHz for top end meters. The display resolution and measurement range capability will typically change
with the applied test frequency since the circuitry is more sensitive or less for a given component (ie, an
inductor or capacitor) as the test frequency changes.

Benchtop LCR meters sometimes have selectable test frequencies of more than 100 kHz. They often
include options to superimpose a DC voltage or current on the AC measuring signal. Lower end meters
might offer the possibility to externally supply these DC voltages or currents while higher end devices can
supply them internally. In addition benchtop meters typically allow the usage of special fixtures (ie, Kelvin
wiring, that is to say, 4-wire connections) to measure SMD components, air-core coils or transformers.
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Bridge circuits

Inductance, capacitance, resistance, and dissipation factor can also be measured by various bridge circuits.
They involve adjusting variable calibrated elements until the signal at a detector becomes null, rather than
measuring impedance and phase angle.

Early commercial LCR bridges used a variety of techniques involving the matching or "nulling" of two
signals derived from a single source. The first signal was generated by applying the test signal to the
unknown and the second signal was generated by using a combination of known-value R and C standards.
The signals were summed through a detector (normally a panel meter with or without some level of
amplification). When zero current was noted by changing the value of the standards and looking for a
"null" in the panel meter, it could be assumed that the current magnitude through the unknown was equal
to that of the standard and that the phase was exactly the reverse (180 degrees apart). The combination of
standards selected could be arranged to read out C and DF directly which was the precise value of the
unknown. An example of this is the GenRad/IET Labs Model 1620 and 1621 Capacitance Bridges.

Measurements of Impedance
Digital LCR meters measure the current (I) flowing through a device under test (DUT), the
voltage (V) across the DUT, and the phase angle between the measured V and I. From these
three measurements, all impedance parameters can then be calculated. A typical LCR meter
has four terminals labeled IH, IL, PH and PL. The IH/IL pair is for the generator and current
measurement and the PH/PL pair is for the voltage measurement.
There are many different methods and techniques for measuring impedance. The most
familiar is the nulling type bridge method. When no current flows through the detector (D),
the value of the unknown impedance Zx can be obtained by the relationship of the other

bridge elements, shown in equation 7.

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Various types of bridge circuits, employing combinations of L, C, and R as bridge elements,

are used in different instruments for varying applications.
Most recently instruments have been developed which employ elaborate software-driven
control and signal processing techniques. For example, the IET Labs 7600 LCR Meter uses a
principle of measurement which differs significantly from that employed by the traditional
measuring instruments. In particular, the 7600 uses digital techniques for signal generation
and detection. Both the voltage across the device under test (Zx) and the voltage across a
reference resistor (Rs) are measured, which essentially carry the same current.
The voltage across Zx is Vx and the voltage across Rs is Vs. Both voltages are
simultaneously sampled many times per cycle of the applied sine wave excitation. In the case
of the 7600, there are four reference resistors. The one used for a particular measurement is
the optimal resistor for the device under test, frequency, and amplitude of the applied AC LCR
Measurement Primersignal. For both Vx and Vs a real and imaginary (in phase and quadrature) component
arecomputed mathematically from the individual sample measurements.
The real and imaginary components of Vx and Vs are by themselves meaningless.
Differences in the voltage and current detection and measurement process are corrected via
software using calibration data. The real and imaginary components of Vx (Vxr and Vxi) are
combined with the real and imaginary components of Vs (Vsr and Vsi) and the known
characteristics of the reference resistor to determine the apparent impedance of the complex impedance of
Zx using complex arithmetic. The step repeat for measurement of capacitance and resistance
VI OBSERVATIONS

s.n XL XC R D Q

VII. CALCULATIONS

VIII. NATURE OF GRAPH

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IX. INFERENCE
Assuming all passive component working ideal condition and t=0 all initial condition assume zero.
Also we assume offset voltage of CRO is zero.
X. PRECAUTIONS
1 Voltage control knob of RPS should be kept at minimum position.
2 Current control knob of RPS should be kept at maximum position
3 Avoid making loose connections.
4 Reading should be taken carefully without parallax error.
XI. TROUBLE SHOOTING:
1.Check the LCR Meter
2.Check the battery connections .

XII RESULTS / CONCLUSIONS

Measure Resistance ,Inductance, Capacitance and Q by DIGITAL LCR meter.

XIV APPLICATIONS
1. LCR meters are available in a wide array of formats, both analog and digital. Analog testers are
more cost-effective and can be constructed using basic components if necessary. Digital testers,
however, provide more accurate readings and are available in smaller sizes and weights.
2. LCR meter is simple to operate.
3.The LCR Meter measures passive components with as little as 0.05 % errors.
4. These easy-to-use instruments are quick to setup, adjust and calibrate.
5. They are ideal for applications such as incoming inspection, quality control, automated test, and
general bench top use

XV QUESTIONS

1. What are Different types of LCR Meters.

2 What is an LCR Meter?

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Experiment No. 6 Amplitude and frequency values of a given waveform derived

Date : from a AF /RF generating instrument.

I AIM: Find out the Amplitude & frequency values of a given Waveform using a CRO from AF&RF
Generating Signal Instrument
II EQUIPMENTS/APPARATUS/COMPONENTS REQUIRE
Apparatus Required
1 CRO
2 Function Generator
3 probes
III THEORY
Measurement of voltage & frequency by oscilloscope of AF & RF signals: Normally an oscilloscope is an
important tool in an electrical field which is used to display the graph of an electrical signals as it varies
with aspect to time.
Measurement of Voltage and Frequency by Oscilloscope
Normally, an oscilloscope is an important tool in an electrical field which is used to display the graph of an
electrical signal as it varies with respect to time. But some of the scopes has additional features apart from
their fundamental use. Many oscilloscopes have the measurement tool that help to measure waveform
characteristics like frequency, voltage, amplitude, and many more features with an accuracy. Generally, a
scope can measure time-based as well as voltage-based characteristics.

Voltage and Frequency Measurement

The oscilloscope is mainly voltage oriented device or we can say that it is a voltage measuring device.
Voltage, current and resistance all are internally related to each other. Just measure the voltage, rest of the
values is obtained by calculation. Voltage is the amount of electric potential between two points in a
circuit. The frequency of a signal is measured using oscilloscope in two methods. They are,
1. Using calibrated oscilloscope
2. Using uncelebrated oscilloscope.
Measurement of Frequency using Calibrated Oscilloscope
It is the indirect method of measurement of frequency. In this method, the frequency of unknown
signal is measured by measuring its time period.
Initially, the unknown frequency signal is applied to the vertical inputs of the CR

IV CIRCUIT DIAGRAM

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V PROCEDURE
Measuring Amplitude and Frequency of Audio frequency (20Hz to 20KHz) and Radio frequency
(20KHz to 300GHz) signals.

1. Apply about 1V, 1KHz of AF signal and 30KHz of RF signal from the signal generator to the Y-input
of CRO. Adjust the time base and Y gain (The calibration knob must turn off as indicated by the
control plate) so that a wave of 2 or 3 cycles is displayed. The amplitude of the wave gives the peak
voltage.
2. Switch off the time base and measure the height of the vertical line.
The length of the line gives the peak-to-peak voltage.
Also, half the vertical line gives the peak voltage.
Measuring frequency
1. Apply about 1V, 1 KHz of AF signal and 30KHz of RF signal from the signal generator to the Y-
input of CRO. Adjust the time base and Y gain (The calibration knob must turn off) so that a
wave of 2 or 3 cycles is displayed. Measure the width of one cycle.

. VI OBSERVATIONS
Measuring Audio frequency signal

Applied frequency Amplitude Time period

1 KHz
10KHz

Measuring Radio frequency signal

Applied frequency Amplitude Time period

30 KHz
80KHz

VII. CALCULATIONS

VIII. NATURE OF GRAPH

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An example of an oscilloscope display. A signal (the yellow sine wave in this case) is graphed on a
horizontal time axis and a vertical voltage axis.

IX. INFERENCE
Assuming all passive component working ideal condition and t=0 all initial condition assume zero.
Also we assume offset voltage of CRO is zero.
X PRECAUTIONS
5 Voltage control knob of RPS should be kept at minimum position.
6 Current control knob of RPS should be kept at maximum position
7 Avoid making loose connections.
8 Reading should be taken carefully without parallax error.
5 Avoid series connection of voltmeters and parallel connection of ammeters.

XI. TROUBLE SHOOTING:

3. Check the probe connection
4. Check the battery connections .Measure V and I with the CRO

XII RESULTS / CONCLUSIONS

Verifying Measurement of Voltage and Frequency o AF signal and Rf signal by Oscilloscope

XIII EXTENSION
Repeat the practical in dual scope CRO
XIV APPLICATIONS
The o-scope is useful in a variety of troubleshooting and research situations, including:

1. Determining the frequency and amplitude of a signal, which can be critical in debugging a circuit’s
input, output, or internal systems. From this, you can tell if a component in your circuit has
malfunctioned.

1. Identifying how much noise is in your circuit.

2. Identifying the shape of a wave – sine, square, triangle, sawtooth, complex, etc.

XV QUESTIONS
Quantifying phase differences between two different signals

What is meant by cathode ray oscilloscope?

What is the use of Lissajous pattern?
What is meant by CRO in electronics?
What is the Lissajous figure?

The Oscilloscope is mainly voltage oriented device or we can say that it is a voltage measuring device
voltage, current and Resistance all are initially related to each other. Just Measure the voltage.

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Charging and discharging curve of a capacitor using digital

Experiment No. 7 CRO and determine time constant of a given RC Circuit
Date :

I AIM: Observe charging and discharging curve of a capacitor using digital CRO and determine time
constant of a given RC Circuit

II EQUIPMENTS/APPARATUS/COMPONENTS REQUIRE
Apparatus Required
1. Digital CRO
2. Function generator
3 Power supply
4 Probes
5 RC Circuit

III THEORY
A digital oscilloscope is an instrument which stores a digital copy of the waveform in the digital memory
which it analyses further using digital signal processing techniques rather than using analogue techniques.
It captures the non-repetitive signals and displays it consciously until the device gets reset. In digital
storage oscilloscope, signals are received, stored and then displayed. The maximum frequency measured
by digital oscilloscope depends upon two things: one is sampling rate of the scope, and the other is the
nature of the converter. Converter is either analogue or digital. The traces in digital oscilloscope are bright,
highly defined, and displayed within seconds as they are non-stored traces. The main advantage of the
digital oscilloscope is that it can display visual as well as numerical values by analyzing the stored traces.
The displayed trace on the flat panel could be magnified and also we can change the brightness of the
traces, and minute detailing can be done as per requirement after an acquisition.

BLOCK DIAGRAM OF DSO

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IV CIRCUIT DIAGRAM

FRONT PANEL OF DSO

CONTROLS

Vertical controls:

 CH 1, CH 2, CH 3 & CH 4 MENU: Displays the vertical menu selections which move the
waveform vertically.
 VOLTS/DIV (CH 1, CH 2, CH 3 & CH 4): Selects vertical scale factors.

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Horizontal controls:

 POSITION: Adjust the horizontal position of waveform. The resolution of horizontal control is a
time function.
 HORIZ MENU: Sets the horizontal position to zero.

 SEC/DIV: Selects the horizontal time/div(scale factor) which set the horizontal gain

Trigger controls:

The trigger determines at what time should Oscilloscope starts to acquire data and to a display a waveform.
The trigger must set properly other wise the wave form display is not stable and some times the screen
goes blank due to synchronization of trigger pulse.

INPUT CONNECTORS

CH1, CH2, CH3 & CH4: Input connectors for waveform display.

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RUN AND STOP BUTTON

RUN BUTTON: With the help run and stop button the experimenter can stop the wave which enhance the
accuracy of fluctuating wave.

AUTO SCALE KEY:This button is used to automatic adjustment of waveform on display panel of DSO.

MEASURE CONTROLS

Digital storage oscilloscope is employed to measure:

 Voltage of the applied signal,

 Frequency of the applied signal,

 Time period of applied signal,

 Amplitude of applied signal,

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 Average RMS value of applied signal, &Duty cycle of applied signal.

CURSORS KNOB- Push this knob select cursors from the menu, rotates the knob to adjust the

selected cursor position.(Cursors) key- Press this key to open a menu that make experimenter to select the
cursors mode and source.

(Meas) key- Press this key to access a set of predefined measurements

RC CIRCUIT

R=100KΩ

C=0.1µF

V=0-20V

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V Procedure and nature of graph

 The objective of observing a signal on the oscilloscope screen is to make voltage and time
measurements.
 These measurements may be helpful in understanding the behavior of a circuit component, or the
circuit itself, depending on what has to be measure.

 The oscilloscope screen consist of the grids which can be external or internal to the screen of CRO,
which divides both the horizontal axis (voltage) and the vertical axis (time) into divisions which
will be helpful in making the measurements.

 These values are determined by two variables namely the time/div and the volt/div both of which
can be adjusted from the relevant buttons available on the front panel of the oscilloscope.

Measurement of A.C. voltage:

 Measurement of peak-to-peak voltage and peak voltage:

1. To measure the ac. voltage of sinusoidal waveform. The input ac. signal is applied from the signal
generator to a channel of CRO. The voltage/div switch (Y-plates) and time base switch (X-plates)
are adjusted such that a steady picture of the waveform is obtained on the screen.

2. The vertical height (l) that is peak-to-peak height is measured. When this peak-to-peak height (L) is
multiplied by the voltage/div (voltage deflection sensitivity ‘n’) we get the peak-to-peak voltage
(2Vo). From this we get the peak voltage (Vo). The rms voltage Vrms is equal to Vo/ 2. This rms
voltage Vrms is verified with rms voltage value, measured by the multimeter.

Measurement of frequency:

 Using time-period:

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Suppose that the time period of the input signal is T. As we know frequency is the reciprocal of time
period.

Then, the frequency of the signal =1/T

Measuring the time constant in RC Circuit

1.First we want to measure the time constant . This means we need to charge the capacitor fully, then
let it discharge through a resistor while we
measure the voltage as it changes over time.
1.Build the charging circuit shown in Fig.4.8(a). Note that the resistor should only be attached at one end
— it’s dangling here. We place it in the circuit so that it is convenient to convert to the discharging circuit
in Fig.4.8(b) Using Digital CRO read DC voltage. Use the DC power supply, a 100 KΩ resistor, and a 1
000μFcapacitor.Check the color code of the resistor to verify that it is 100KΩ and check its tolerance.
Your instructor will tell you the tolerance of the capacitor, which is likely to be±20%. The resistor codes
can be found in Fig.4.7

2. Use the power supply to charge the capacitor to approximately 12–13

V. Then disconnect the power supply from the circuit by unplugging the wires from the power supply
without turning it off. Notice that the voltage across the capacitor slowly decrease

3. Build the discharging circuit shown in Fig.4.8(b). Find a banana plug from a bucket in the front of the
room. In this circuit, it will clip to another wire connector and make an effective switch. After building the
circuit shown in this figure with your “switch” unconnected (i.e “open”) the capacitor should still be
charged from the previous step but you should notice that the voltage is slowly decreasing.
.
4.Close the switch by connecting the banana plug and notice the voltmeter starts to register that the charge
on the capacitor is decreasing as it discharges through the resistor. Let it go until the voltage across the
capacitor has dropped to about 10 or 11 volts, then start the timer and record the time and voltage in Table
1 of your spreadsheet. Continue recording the voltage across the capacitor once every 10 seconds until
your timer has reached 300 seconds.

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VI OBSERVATIONS

Sno amplitude time No of cycle

VII. CALCULATIONS

Frequency=no of cycle/ time

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VIII. NATURE OF GRAPH

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IX. INFERENCE
Assuming all passive component working ideal condition and t=0 all initial condition assume zero.
Also we assume offset voltage of CRO is zero.

X PRECAUTIONS
1. Voltage control knob of RPS should be kept at minimum position.
2. Current control knob of RPS should be kept at maximum position
3. Avoid making loose connections.
4. Reading should be taken carefully without parallax error.
5 Avoid series connection of voltmeters and parallel connection of ammeters.

XI. TROUBLE SHOOTING:

1. Check the probe connection
2. Check the battery connections .Measure V and I with the cro

XII RESULTS / CONCLUSIONS

Verifying CRO front panel controls and observe thecharging and discharging curves of capacitor.
XIII EXTENSION
Repeat the practical in dual scope CRO
XIV APPLICATIONS
Uses of Digital Storage Oscilloscope
1. Used for testing signal voltage in circuit debugging.
2. Testing in manufacturing.
3. Designing.
4. Testing of signals voltage in radio broadcasting equipment.
5. In the field of research.
6. Audio and video recording equipme

XV QUESTIONS
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1. Define DIGITAL STORAGE OSCILLOSCOPE?

2. Who discover DSO?

3. The analog signal is converted to the digital signal by _________.

4. What is the principle of operation of digital storage oscilloscope?

5. State whether the statement is true or false “the signal in DSO can used even after the original
circuitry is not available” justify your answer?

6. Define memory and explain how it can store the digital data?

7. The data acquiring is stopped by pressing ________ button in DSO?

8. Before the signal displayed on DSO screen which converter is used:

a. analog to digital convertor. b. digital to analog convertor.

9. Which oscilloscope is more user friendly:

a. analog oscilloscope. b. digital oscilloscope.

10. To vary the time period of the signal which control panel is used?

11. In DSO the signals are displayed on __________ screen.

12. Differentiate between analog type oscilloscope and digital oscilloscope which one is preferable
and why?

Measure the rise time ,fall time , duty cycle pulse width , pulse
Experiment No. 8 amplitude overshoot pulse on CRO

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I AIM : To measure the rise time ,fall time , duty cycle pulse width , pulse amplitude overshoot pulse on
CRO

II EQUIPMENTS/APPARATUS/COMPONENTS REQUIRE
Apparatus Required
1 CRO
2 FUNCTION GENERATOR
3 CONECTING WIRE

III THEORY

Rise time

Rise time is the time taken for a signal to cross a specified lower voltage threshold followed by a specified
upper voltage threshold. This is an important parameter in both digital and analog systems. In digital
systems it describes how long a signal spends in the intermediate state between two valid logic levels. In
analog systems it specifies the time taken for the output to rise from one specified level to another when
the input is driven by an ideal edge with zero rise time. This indicates how well the system preserves a fast
transition in the input signal.

Rise time and bandwidth

So why do we need to know the rise time of an oscilloscope? The rise time of an amplifier is related to its
bandwidth. If we know the bandwidth of the signal under test, we can choose an oscilloscope with an equal
or greater system bandwidth and be confident that the oscilloscope will display the signal accurately. If, on
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the other hand, we know the rise time of our signal, it would be useful to know by how much the
oscilloscope will slow down the signal and therefore add to its rise time.

The bandwidth BW in hertz of an amplifier with a rise time of tR seconds can be estimated as:

BW ≈ 0.35 / tR

BW and tR can be scaled to more convenient units such as MHz and µs, or GHz and ns.

The numerator of 0.35 in this formula is accurate if the oscilloscope's input amplifier has a simple
frequency response like that of a single-pole RC filter. In reality, many oscilloscopes have a faster roll-off
to give a flatter frequency response in the pass band, and this can increase the numerator to 0.45 or even
higher. The formula also assumes that the rise time is measured between the 10% and 90% voltage levels
of the signa

Rise time, Fall time, Duty cycle and Time Period of square pulse.

Rise time: - The time required for a signal to transit from 10% of its maximum value upto 90% of its
maximum value.

Fall time: - The time required for a signal to transit from 90% of its maximum value down to 10% of its
maximum value.

Duty cycle: - For periodic rectangular waveform, the ratio of the time the signal is high to the time period
of the signal.

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Pulse Width (PW) is the elapsed time between the rising and falling edges of a single pulse. To make this
measurement repeatable and accurate, we use the 50% power level as the reference points.

Pulse Repetition Interval (PRI) is the time between sequential pulses. We typically measure PRI as the
time from the beginning of one pulse and the beginning of the next. We use PRI to report the number of
seconds per pulse.

Pulse Repetition Frequency (PRF) is the reciprocal of PRI. The basic unit of measure for PRF is hertz
(Hz). Use PRF to report the number of pulses per second. Look at a 1 GHz clock signal as an example. The
clock signal is a continuing stream of pulses at a PRF of 1 GHz.

Why use PRF instead of just saying Frequency?

The difference is in the types of signal we are measuring. Use Frequency for analog, continuous,
waveforms, like sine and cosine waves. For digital, discrete waveforms, like clocks and pulsed signals, we
use PRF for clarity. The two types of signals behave differently so it’s important to avoid confusion when
you are discussing them.

Duty Cycle describes the “On Time” for a pulsed signal. We can report duty cycle in units of time, but
usually as a percentage. Like Pulse Width and Repetition Frequency, a signal’s duty cycle is a calculated
value; not directly measured. To calculate a signal’s duty cycle, we need to know the signal’s pulse width
and repetition frequency. Use this equation for calculating a signal’s duty cycle as a percentage of the
repetition frequency:

 Duty Cycle = Pulse Width (sec) * Repetition Frequency (Hz) * 100

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IV CIRCUIT DIAGRAM

PROCEDURE:
1. Connect the circuit as per the circuit diagram.
2. Give the input square wave from the function generator.
3. Observe the output waveform across collector and ground terminal.
4. Notedown the values from CRO rise time , fall time, pulse width and amplitude.
5. Calculate the duty cycle and overshoot.

VII. CALCULATIONS

Duty Cycle = Pulse Width (sec) * Repetition Frequency (Hz) * 100

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VIII. NATURE OF GRAPH

IX. INFERENCE
Assuming all passive component working ideal condition and t=0 all initial condition assume zero.
Also we assume offset voltage of CRO is zero.
X PRECAUTIONS
 Voltage control knob of RPS should be kept at minimum position.
 Current control knob of RPS should be kept at maximum position
 Avoid making loose connections.
 Reading should be taken carefully without parallax error.
5 Avoid series connection of voltmeters and parallel connection of ammeters.

XI. TROUBLE SHOOTING:

5. Check the probe connection
6. Check the battery connections .Measure V and I with the CRO

XII RESULTS / CONCLUSIONS

Result : Verify the measurment of rise time, fall time, duty cycle, pulse width, pulse amplitude,
overshoot pulse on CRO
XIII EXTENSION
Dual scope CRO
XIV APPLICATIONS
1. Amplitude and frequency modulation
2. Digital modulation

XV QUESTIONS
1 What is rise time and fall time of a waveform?
2 What is the bandwidth of an oscilloscope?
3 What is the fall time?
4 What is settling time in control system?

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Experiment No.9 Observe and sketch the waveform of a given RC differentiator network being
driven by a pulse (pulse width t d) under the following conditions. 1) RC>> t d 2)
RC<< td 3) RC=td

I AIM : To observe and sketch the waveform of a given RC differentiator network being driven by a pulse
(pulse width t d) under the following conditions. 1) RC>> t d 2) RC<< td 3) RC=td

II EQUIPMENTS/APPARATUS/COMPONENTS REQUIRE

Apparatus Required

1 distortion factor meter

2 CRO
3 PROBES
4 POWER SUPPLY
5 FUNCTION GENERATOR
6 CAPACITOR(0.1µF)
7.RESISTORS(100Ω, 1KΩ, 10KΩ)
III THEORY

The RC Differentiator : The Differentiator is a High Pass Filter type of circuit that can convert a square
wave input signal into high frequency spikes at its output. If the 5RC time constant is short compared to
the time period of the input waveform, then the capacitor will become fully charged more quickly before
the next change in the input cycle. When the capacitor is fully charged the output voltage across the
resistor is zero. The arrival of the falling edge of the input waveform causes the capacitor to reverse charge
giving a negative output spike, then as the square wave input changes during each cycle the output spike
changes from a positive value to a negative value.
IV CIRCUIT DIAGRAM and.NATURE OF GRAPH

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Note:
High Pass Filter block the DC component of I/P Signal.

Procedure:

1 Connect the circuit as shown in figure (HPF)

2 Apply the Square wave input to this circuit (Vi=4 VP-P, f= 10KHz)
3 Observe the output waveform for (a) RC-T. (b) RC>>T. (c) RC>>T
4 Verify the values with theoretical calculations

Precautions:
Use two CRO probes and observe I/P & O/P waveforms simultaneously by putting CRO on DC
modes.

Result:

HPF are designed at various time constants and the responses for square wave input is
observed & hence plotted

Experiment Observe and sketch the waveform of a given RC integrator network being driven
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No.10 by a pulse (pulse width t d) under the following conditions. 1) RC>> t d 2) RC<<
td 3) RC=td

I AIM : To observe and sketch the waveform of a given RC integrator network being driven by a pulse
(pulse width t d) under the following conditions. 1) RC>> t d 2) RC<< td 3) RC=td

II EQUIPMENTS/APPARATUS/COMPONENTS REQUIRE

Apparatus Required

1 distortion factor meter

2 CRO
3 PROBES
4 POWER SUPPLY
1 FUNCTION GENERATOR
2 CAPACITOR(0.1µF)
7.RESISTORS(100Ω, 1KΩ, 10KΩ)

III THEORY

The RC Integrator

The Integrator is a type of Low Pass Filter circuit that converts a square wave input signal into a
triangular waveform output. As seen above, if the 5RC time constant is long compared to the time period
of the input RC waveform the resultant output will be triangular in shape and the higher the input
frequency the lower will be the output amplitude compared to that of the input.

IV CIRCUIT DIAGRAM

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Note:
High Pass Filter block the DC component of I/P Signal.

Procedure:

1 Connect the circuit as shown in figure (HPF)

2 Apply the Square wave input to this circuit (Vi=4 VP-P, f= 10KHz)
3 Observe the output waveform for (a) RC-T. (b) RC>>T. (c) RC>>T
4 Verify the values with theoretical calculations

Precautions:
Use two CRO probes and observe I/P & O/P waveforms simultaneously by putting CRO on DC
modes.
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Result:

HPF are designed at various time constants and the responses for square wave input is
observed & hence plotted

Questions:

1. When HP-RC circuit is used as Differentiator?

2. Draw the responses of HPF to step, pulse, ramp inputs? LPF to step, pulse, ramp inputs?

3. Draw the responses of 4. Define % tilt and rise time?

5. When LP-RC circuit is used as integrator?

6. Why noise immunity is more in integrator than differentiator? 7. Why HPF blocks the DC signal?

8. Define Idb?

9. What is meant by linear wave shaping?

10. Write the formula for rise time t

Experiment No.11 Demonstrate the use of integrator circuit for producing triangular wave / Ramp
through a square wave using a CRO.

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RC INTEGRATOR CIRCUIT

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Experiment No.12 Design a Low pass filter using a given Integrator circuit (RC) for a given cut off
frequency say 1KHz.

Aim: To design a low pass filter using a given integrator circuit (RL) for a given cut-off frequency say
1Khz

Apparatus Required:-

1. CRO- INO

2. Function generator - - INO Bread Board - INO

3. Capacitor (0.01µF)-1NO

4. Resistor (15KΩ) -INO

5. Connecting wires.

Theory:- Low pass filter design equation

Fc =1/2πRC

IV CIRCUIT DIAGRAM

R=15KΩ
C=0.01µF
Vin=4Vp-p.
Vo in CRO

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DESIGN OF LOWPASS FILTER WITH 1KHz:

Fc =1/2πRC
Fc=1Khz
C=0.01×10-6 F
R=?
R=1/2πFcC
=>1/(2π×1×103×0.01×10-6)
R=15KΩ

Procedure

1. Connect the circuit as per the circuit diagram.

2. Give input from function generator that is fc = 1KHz &. input voltage is 4Vp-p.

3. By varying the input frequency values from 100 Hz to 10KHz to note down the output voltage
values from the CRO.

4. Calculate the Gain (Vo/Vi) in db and draw the graph frequency (Vs) Gain in db in
logarithmic graph.

Observation Table: Vin =4Vp-p.

S.no Frequency Vo Gain=Vo/Vin Gain in db=20log(Vo/Vin)

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Expected Graph:

PRECAUTIONS
 Voltage control knob of RPS should be kept at minimum position.
 Current control knob of RPS should be kept at maximum position
 Avoid making loose connections.
 Reading should be taken carefully without parallax error.
5 Avoid series connection of voltmeters and parallel connection of ammeters.

TROUBLE SHOOTING

 Make sure that the ground of the oscilloscope and power supply are the same.
After completing each circuit, turn off the power to allow the op amp to completely discharge. Use the
oscilloscope to observe the voltage waveform as it goes to zero (in 5 – 10 seconds)

RESULTS / CONCLUSIONS

Designed & implemented an RC circuit as an integrator with frequency of 1Khz

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Experiment No.13 Design a Low pass filter using a given Integrator circuit (RC) for a given cut off
frequency say 2KHz.

Aim: To design a low pass filter using a given integrator circuit (RL) for a given cut-off frequency say
2Khz

Apparatus Required:-

6. CRO- INO

7. Function generator - - INO Bread Board - INO

8. Capacitor (0.01µF)-1NO

9. Resistor (7.9KΩ) -INO

10. Connecting wires.

Theory:- Low pass filter design equation

Fc =1/2πRC

IV CIRCUIT DIAGRAM

R=8.2KΩ
C=0.01µF
Vin=4Vp-p.
F=2Khz
Vo in CRO

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DESIGN OF LOWPASS FILTER WITH 1KHz:

Fc =1/2πRC
Fc=2Khz
C=0.01×10-6 F
R=?
R=1/2πFcC
=>1/(2π×2×103×0.01×10-6)
R=7.9KΩ
Approximately take 8.2KΩ

Procedure

5. Connect the circuit as per the circuit diagram.

6. Give input from function generator that is fc = 2KHz &. input voltage is 4Vp-p.

7. By varying the input frequency values from 100 Hz to 10KHz to note down the output voltage
values from the CRO.

8. Calculate the Gain (Vo/Vi) in db and draw the graph frequency (Vs) Gain in db in
logarithmic graph.

Observation Table: Vin =4Vp-p.

S.no Frequency Vo Gain=Vo/Vin Gain in db=20log(Vo/Vin)

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Expected Graph:

PRECAUTIONS
 Voltage control knob of RPS should be kept at minimum position.
 Current control knob of RPS should be kept at maximum position
 Avoid making loose connections.
 Reading should be taken carefully without parallax error.
 Avoid series connection of voltmeters and parallel connection of ammeters.

TROUBLE SHOOTING

 Make sure that the ground of the oscilloscope and power supply are the same.
After completing each circuit, turn off the power to allow the op amp to completely discharge. Use the
oscilloscope to observe the voltage waveform as it goes to zero (in 5 – 10 seconds)

RESULTS / CONCLUSIONS

Designed & implemented an RC circuit as an integrator with frequency of 2Khz

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Experiment No.14 Realize a series clipper and observe the waveform on a CRO.

I AIM: To realize a series clipper and observe the waveform on a CRO

Apparatus:

S.No Name of the component/Equipments Specification Quantity

1. Resistors 1kΩ 1
2.2KΩ 1
2. Diodes 1N4007 1
3. Bread board 1
4. Connecting wires 1 Bunch
5. Function generator 1
6. CRO 1
Theory:

A clipping circuit comprises of linear elements like resistors and non-linear elements
like diodes or transistor, but it does not contain energy storage elements capacitors. Clipping
circuits basically limit the amplitude of the input signal either below or above certain voltage
level. They are referred to as Voltage limiters, Amplitude selectors or Slicers. A clipping
circuit is one, in which a small section of input waveform is missing or cut or truncated at the
output section. Clipping circuits are classified based on the position of Diode. 1.Series
Diode Clipper 2.Shunt Diode Clipper.

CIRCUIT DIAGRAM

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Procedure:

1. Connect the circuit as shown in fig.1

2. In each case apply 10 VP-P, 1 KHz Sine wave i/p using a signal generator.
3. O/P is taken across the load RL.
4. Observe the O/P waveform on the CRO and compare with i/p waveform.
5. Sketch the i/p as well as o/p waveforms and mark the numerical values.
6. Obtain the transfer characteristics of Fig.1, by keeping CRO in X-Y mode.
7. Repeat the above steps for all the circuit.
Input Wave Form

Output wave form for Series Diode Clipper:

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Precautions:

a. Set the CRO O/P channel in DC mode always.

b. Observe the waveform simultaneously by keeping common ground.
c. See that there is no DC component in the I/P.
d. To find transfer characteristics apply input to the X-Channel, O/P to Y-Channel, adjust the
dot at the center of the screen when CRO is in X-Y mode. Both the channels must be in
ground, then remove ground and plot the transfer characteristics

Result:

Different types of clipping circuits have been studied and observed the responses for
various combinations of VR and clipping diodes.
Questions:

1. Define clipping circuit?

2. What are the different types of clippers?
3. What is a break region

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Experiment No.15 Realize a parallel clipper and observe the waveform on a CRO

I AIM: To realize a parallel clipper and observe the waveform on a CRO

Apparatus:

S.No Name of the component/Equipments Specification Quantity

1. Resistors 1kΩ 1
2.2KΩ 1
2. Diodes 1N4007 1
3. Bread board 1
4. Connecting wires 1 Bunch
5. Function generator 1
6. CRO 1
Theory:

A clipping circuit comprises of linear elements like resistors and non-linear elements
like diodes or transistor, but it does not contain energy storage elements capacitors. Clipping
circuits basically limit the amplitude of the input signal either below or above certain voltage
level. They are referred to as Voltage limiters, Amplitude selectors or Slicers. A clipping
circuit is one, in which a small section of input waveform is missing or cut or truncated at the
output section. Clipping circuits are classified based on the position of Diode. 1.Series
Diode Clipper 2.Shunt Diode Clipper.
CIRCUIT DIAGRAM
Shunt Diode Negative Clipper:

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Shunt Diode Positive Clipper:

Procedure:

1. Connect the circuit as shown in fig.

2. In each case apply 10 VP-P, 1 KHz Sine wave i/p using a signal generator.
3. O/P is taken across the load RL.
4. Observe the O/P waveform on the CRO and compare with i/p waveform.
5. Sketch the i/p as well as o/p waveforms and mark the numerical values.
6. Obtain the transfer characteristics of Fig.1, by keeping CRO in X-Y mode.
7. Repeat the above steps for all the circuit.
Precautions:

a. Set the CRO O/P channel in DC mode always.

b. Observe the waveform simultaneously by keeping common ground.
c. See that there is no DC component in the I/P.
d. To find transfer characteristics apply input to the X-Channel, O/P to Y-Channel, adjust the
dot at the center of the screen when CRO is in X-Y mode. Both the channels must be in
ground, then remove ground and plot the transfer characteristics

Result:

Different types of clipping circuits have been studied and observed the responses for
various combinations of VR and clipping diodes.

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Experiment No.16 Realize a positive clipper without bias and observe the waveform on a CRO.

I AIM: To realize a positive clipper without bias and observe the waveform on a CRO.

Apparatus:

S.No Name of the component/Equipments Specification Quantity

1. Resistors 1kΩ 1
2.2KΩ 1
2. Diodes 1N4007 1
3. Bread board 1
4. Connecting wires 1 Bunch
5. Function generator 1
6. CRO 1
Theory:

A clipping circuit comprises of linear elements like resistors and non-linear elements
like diodes or transistor, but it does not contain energy storage elements capacitors. Clipping
circuits basically limit the amplitude of the input signal either below or above certain voltage
level. They are referred to as Voltage limiters, Amplitude selectors or Slicers. A clipping
circuit is one, in which a small section of input waveform is missing or cut or truncated at the
output section. Clipping circuits are classified based on the position of Diode. 1.Series
Diode Clipper 2.Shunt Diode Clipper.
CIRCUIT DIAGRAM

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Procedure:

1. Connect the circuit as shown in fig.

2. In each case apply 10 VP-P, 1 KHz Sine wave i/p using a signal generator.
3. O/P is taken across the load RL.
4. Observe the O/P waveform on the CRO and compare with i/p waveform.
5. Sketch the i/p as well as o/p waveforms and mark the numerical values.
6. Obtain the transfer characteristics of Fig.1, by keeping CRO in X-Y mode.
7. Repeat the above steps for all the circuit.
Precautions:

1. Set the CRO O/P channel in DC mode always.

2. Observe the waveform simultaneously by keeping common ground.
3. See that there is no DC component in the I/P.
4. To find transfer characteristics apply input to the X-Channel, O/P to Y-Channel, adjust
the dot at the center of the screen when CRO is in X-Y mode. Both the channels must be
in ground, then remove ground and plot the transfer characteristics

Result:

Different types of clipping circuits have been studied and observed the responses for
various combinations of VR and clipping diodes.
Questions:

4. Define clipping circuit?

5. What are the different types of clippers?
6. What is a break region

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Experiment No.17 Realize a positive clipper with bias and observe the waveform on a CRO.

I AIM: To realize a positive clipper with bias and observe the waveform on a CRO.
Apparatus:

S.No Name of the component/Equipments Specification Quantity

1. Resistors 1kΩ 1
2.2KΩ 1
2. Diodes 1N4007 1
3. Bread board 1
4. Connecting wires 1 Bunch
5. Function generator 1
6. CRO 1
7. RPS 1
Theory:

A clipping circuit comprises of linear elements like resistors and non-linear elements
like diodes or transistor, but it does not contain energy storage elements capacitors. Clipping
circuits basically limit the amplitude of the input signal either below or above certain voltage
level. They are referred to as Voltage limiters, Amplitude selectors or Slicers. A clipping
circuit is one, in which a small section of input waveform is missing or cut or truncated at the
output section. Clipping circuits are classified based on the position of Diode. 1.Series
Diode Clipper 2.Shunt Diode Clipper.
CIRCUIT DIAGRAM

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Procedure:

1. Connect the circuit as shown in fig.1

2. In each case apply 10 VP-P, 1 KHz Sine wave i/p using a signal generator.
3. O/P is taken across the load RL.
4. Observe the O/P waveform on the CRO and compare with i/p waveform.
5. Sketch the i/p as well as o/p waveforms and mark the numerical values.
6. Note the changes in the O/P due to variations in the reference
voltage VR = 2V, 3V.
7. Obtain the transfer characteristics of Fig.1, by keeping CRO in X-Y mode.
8. Repeat the above steps for all the circuit.
Precautions:

1. Set the CRO O/P channel in DC mode always.

2. Observe the waveform simultaneously by keeping common ground.
3. See that there is no DC component in the I/P.
4. To find transfer characteristics apply input to the X-Channel, O/P to Y-Channel,
adjust the dot at the center of the screen when CRO is in X-Y mode. Both the
channels must be in ground, then remove ground and plot the transfer
characteristics.

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Result:

Different types of clipping circuits have been studied and observed the responses for
various combinations of VR and clipping diodes.

Questions:

1. Define clipping circuit?

2. What are the different types of clippers?
3. What is a break region?
4. Which kind of a clipper is called a slicer circuit?
5. What are the disadvantages of the shunt clipper?
6. What are the disadvantages of the series clipper?
7. What is piecewise linear mode of a diode?

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Experiment No.18 Realize a negative clipper without bias and observe the waveform on a CRO.

I AIM: To realize a negative clipper without bias and observe the waveform on a CRO.
Apparatus:

S.No Name of the component/Equipments Specification Quantity

1. Resistors 1kΩ 1
2.2KΩ 1
2. Diodes 1N4007 1
3. Bread board 1
4. Connecting wires 1 Bunch
5. Function generator 1
6. CRO 1

Theory:

A clipping circuit comprises of linear elements like resistors and non-linear elements
like diodes or transistor, but it does not contain energy storage elements capacitors. Clipping
circuits basically limit the amplitude of the input signal either below or above certain voltage
level. They are referred to as Voltage limiters, Amplitude selectors or Slicers. A clipping
circuit is one, in which a small section of input waveform is missing or cut or truncated at the
output section. Clipping circuits are classified based on the position of Diode. 1.Series
Diode Clipper 2.Shunt Diode Clipper.
CIRCUIT DIAGRAM

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Procedure:

1. Connect the circuit as shown in fig.1

2. In each case apply 10 VP-P, 1 KHz Sine wave i/p using a signal generator.
3. O/P is taken across the load RL.
4. Observe the O/P waveform on the CRO and compare with i/p waveform.
5. Sketch the i/p as well as o/p waveforms and mark the numerical values
6. Obtain the transfer characteristics of Fig.1, by keeping CRO in X-Y mode.
7. Repeat the above steps for all the circuit.
Precautions:

1. Set the CRO O/P channel in DC mode always.

2. Observe the waveform simultaneously by keeping common ground.
3. See that there is no DC component in the I/P.
4. To find transfer characteristics apply input to the X-Channel, O/P to Y-
Channel, adjust the dot at the center of the screen when CRO is in X-Y
mode. Both the channels must be in ground, then remove ground and plot
the transfer characteristics.
Result:

Different types of clipping circuits have been studied and observed the responses for
various combinations of VR and clipping diodes.

Questions:

i. Define clipping circuit?

ii. What are the different types of clippers?
iii. What is a break region?
iv. Which kind of a clipper is called a slicer circuit?
v. What are the disadvantages of the shunt clipper?
vi. What are the disadvantages of the series clipper?
vii.

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Experiment No.19 Realize a negative clipper with bias and observe the waveform on a CRO.

I AIM: To realize a negative clipper with bias and observe the waveform on a CRO.

Apparatus:

S.No Name of the component/Equipments Specification Quantity

1. Resistors 1kΩ 1
2.2KΩ 1
2. Diodes 1N4007 1
3. Bread board 1
4. Connecting wires 1 Bunch
5. Function generator 1
6. CRO 1
7. RPS 1
Theory:

A clipping circuit comprises of linear elements like resistors and non-linear elements
like diodes or transistor, but it does not contain energy storage elements capacitors. Clipping
circuits basically limit the amplitude of the input signal either below or above certain voltage
level. They are referred to as Voltage limiters, Amplitude selectors or Slicers. A clipping
circuit is one, in which a small section of input waveform is missing or cut or truncated at the
output section. Clipping circuits are classified based on the position of Diode. 1.Series
Diode Clipper 2.Shunt Diode Clipper.
CIRCUIT DIAGRAM

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Procedure:

1. Connect the circuit as shown in fig.1

2. In each case apply 10 VP-P, 1 KHz Sine wave i/p using a signal generator.
3. O/P is taken across the load RL.
4. Observe the O/P waveform on the CRO and compare with i/p waveform.
5. Sketch the i/p as well as o/p waveforms and mark the numerical values.
6. Note the changes in the O/P due to variations in the reference
voltage VR = 2V, 3V.
7. Obtain the transfer characteristics of Fig.1, by keeping CRO in X-Y mode.
8. Repeat the above steps for all the circuit.
Precautions:

1. Set the CRO O/P channel in DC mode always.

2. Observe the waveform simultaneously by keeping common ground.
3. See that there is no DC component in the I/P.
4. To find transfer characteristics apply input to the X-Channel, O/P to Y-
Channel, adjust the dot at the center of the screen when CRO is in X-Y
mode. Both the channels must be in ground, then remove ground and plot
the transfer characteristics.

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Result:

Different types of clipping circuits have been studied and observed the responses for
various combinations of VR and clipping diodes.

Questions:

i. Define clipping circuit?

ii. What are the different types of clippers?
iii. What is a break region?
iv. Which kind of a clipper is called a slicer circuit?
v. What are the disadvantages of the shunt clipper?
vi. What are the disadvantages of the series clipper?
vii. What is piecewise linear mode of a diode?

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Experiment No.20 Realize a zener diode clipper and observe the wave form on a CRO.

I AIM: Realize a zener diode clipper and observe the wave form on a CRO.
Apparatus:

S.No Name of the component/Equipments Specification Quantity

1. Resistors 1kΩ 1
2.2KΩ 1
2. Zener Diodes 2N2222 2
3. Bread board 1
4. Connecting wires 1 Bunch
5. Function generator 1
6. CRO 1
7. RPS 1
Theory:
Zener Diode Clipping

The zener diode is acting like a biased diode clipping circuit with the bias voltage
being equal to the zener breakdown voltage. In this circuit during the positive half of the
waveform the zener diode is reverse biased so the waveform is clipped at the zener
voltage, VZD1. During the negative half cycle the zener acts like a normal diode with its
usual 0.7V junction value.
We can develop this idea further by using the zener diodes reverse-voltage
characteristics to clip both halves of a waveform using series connected back-to-back zener
diodes as shown.

Full-wave Zener Diode Clipping

The output waveform from full wave zener diode clipping circuits resembles that of
the previous voltage biased diode clipping circuit. The output waveform will be clipped at the
zener voltage plus the 0.7V forward volt drop of the other diode. So for example, the positive
half cycle will be clipped at the sum of zener diode, ZD1 plus 0.7V from ZD2 and vice versa
for the negative half cycle.
Zener diodes are manufactured with a wide range of voltages and can be used to give
different voltage references on each half cycle, the same as above. Zener diodes are available
with zener breakdown voltages, VZ ranging from 2.4 to 33 volts, with a typical tolerance of 1
or 5%. Note that once conducting in the reverse breakdown region, full current will flow
through the zener diode so a suitable current limiting resistor, R1 must be chosen.

CIRCUIT DIAGRAM:
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Procedure:

1. Connect the circuit as shown in fig.1

2. In each case apply 10 VP-P, 1 KHz Sine wave i/p using a signal generator.
3. O/P is taken across the load RL.
4. Observe the O/P waveform on the CRO and compare with i/p waveform.
5. Sketch the i/p as well as o/p waveforms and mark the numerical values.
6. Note the changes in the O/P due to variations in the reference
voltage VR = 2V, 3V.
7. Obtain the transfer characteristics of Fig.1, by keeping CRO in X-Y mode.
8. Repeat the above steps for all the circuit.
Precautions:

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i. Set the CRO O/P channel in DC mode always.

ii. Observe the waveform simultaneously by keeping common ground.
iii. See that there is no DC component in the I/P.
iv. To find transfer characteristics apply input to the X-Channel, O/P to Y-
Channel, adjust the dot at the center of the screen when CRO is in X-Y
mode. Both the channels must be in ground, then remove ground and
plot the transfer characteristics.

Result:

Different types of clipping circuits have been studied and observed the responses for
various combinations of VR and clipping diodes.

Questions:

viii. Define clipping circuit?

ix. What are the different types of clippers?
x. What is a break region?
xi. Which kind of a clipper is called a slicer circuit?
xii. What are the disadvantages of the shunt clipper?
xiii. What are the disadvantages of the series clipper?
xiv. What is piecewise linear mode of a diode?

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Experiment No.21 Realize a Clamper circuit and observe the input and output waveforms on CRO.

Aim: To study the clamping circuits using diodes and capacitors.

Apparatus:

S.No Name of the component Specification Quantity

1. Resistors 100kΩ 1
2. Diodes 1N4007 1
3. Capacitor 0.1µf
4. Bread board 1
5. Connecting wires 1 Bunch
6. Function generator 1
7. CRO 1
8. Dual Regulated Power supply (0-30) V DC 1

Circuit Diagrams:

Negative Clamper

Positive Clamper

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Biased –Ve clamper (-Vr)

Biased +Ve Clamper:

Theory:
Clamping circuits add a DC level to an AC signal. A clamper is also refer to as
DC restorer or DC reinserted. The Clampers which clamp the given waveform either
above or below the reference level, which are known as positive or negative clamping
respectively.

They are of two types

(i) Negative clamper.
(ii) Positive clamper.

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Negative clamper is also termed as positive peak clamper, since circuit clamps the
positive peak to zero level. Similarly positive clamper is termed as negative peak
clamper, since the circuit clamps the negative peak to zero level.

Procedure:
1. Connect the circuit as shown in fig.1.
2. Apply a Sine wave of 10VP-P, 1KHz at the input terminals with the help of
Signal Generator.
3. Observe the I/P & O/P waveforms of CRO and plot the waveforms and mark
the values with VR =2 V, 3V
4. O/P is taken across the load RL.
5. Repeat the above steps for all clamping circuits as shown.
6. Waveforms are drawn assuming diode is ideal
Model graph:I/P Wave Form

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Out put wave forms for –ve Clamper:

Out put wave forms for +ve Clamper:

Biased –Ve Clamper

Biased +Ve Clamper:

Result:

Different types of clamping circuits are studied and observed the response for
different combinations of VR and diodes.

Questions: 1.What are the applications of clamping circuits?

2. What is the synchronized clamping?
3. Why clamper is called a dc inserter?

INDUR Institute of Engineering & Technology Dept.ECE 84

 Dept. of Electronics & Communication Engg.

Experiment No.22 SERIES RESONANCE CIRCUIT.

Aim: To Plot the resonance curve of a given series tuned circuit.

. Apparatus:

S.No Name of the component Specification Quantity

1. Resistors 10Ω 1
2. Inductance Box 100mH 1
3. Capacitor 0.047µf 1
4. Bread board 1
5. Connecting wires 1 Bunch
6. Function generator 1
7. CRO 1
THEORY:
A resonant circuit consists of R, L, and C elements and whose frequency response characteristic
changes with changes in frequency.
In a series RLC circuit there becomes a frequency point were the inductive reactance of the
inductor becomes equal in value to the capacitive reactance of the capacitor. In other words, XL = XC.
The point at which this occurs is called the Resonant Frequency point, ( ƒr ) of the circuit, and as we
are analyzing a series RLC circuit this resonance frequency produces a Series Resonance.
Series Resonance circuits are one of the most important circuits used electrical and electronic
circuits. They can be found in various forms such as in AC mains filters, noise filters and also in radio
and television tuning circuits producing a very selective tuning circuit for the receiving of the different
frequency channels.
In a series resonant circuit, the resonant frequency, ƒr point can be calculated as follows.

INDUR Institute of Engineering & Technology Dept.ECE 85

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Circuit Diagrams:

PROCEDURE:

1. Connect sine wave generator at the input of the filter. Adjust sine wave
amplitude to 5Volt p-p. Keep the input voltage constant throughout the
experiment.
2. Connect CRO at the output of the filter.
3. Vary the input frequency from minimum to 1KHz in proper steps in sine wave
generator and every time note the input frequency and corresponding output
voltage from the CRO in the observation table.
4. Plot the graph between input frequency & Output Voltage taking input
frequency (in Hz) on x-axis and output voltage (in Volts) on y- axis on semi log
graph paper.
5. Calculate the cut-off frequency from the formula as well as from the graph.
OBSERVATIONS

OBSERVATION TABLE:

S.No. Input Output

frequency Voltage
(in Hz) (in
Volts)
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.

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Model graph:

PRECAUTIONS
 Voltage control knob of RPS should be kept at minimum position.
 Current control knob of RPS should be kept at maximum position
 Avoid making loose connections.
 Reading should be taken carefully without parallax error.
Avoid series connection of voltmeters and parallel connection of ammeters.

TROUBLE SHOOTING:
1. Check the probe connection
2. Check the battery connections .Measure V and I with the CRO
RESULTS / CONCLUSIONS

RESULT: frequency response of series resonance circuit is verified.

APPLICATIONS
1. These are used in the loud speakers to reduce the low level noise.
2. Eliminates rumble distortions in audio applications so these are also called are treble boost
filters.
3. These are used in audio amplifiers to amplify the higher frequency signals.
4. These are also used in equalizers.

XVQUESTIONS
VIVA QUESTIONS
1.What is a const. k filter ?
2.ZOT=?
3.Z1Z2=?
4.Is/IR=?
5.Make T & π sections ?
6.Relation between ZOT & ZOπ ?

INDUR Institute of Engineering & Technology Dept.ECE 87

 Dept. of Electronics & Communication Engg.

Experiment No.23 PARALLEL RESONANCE CIRCUIT.

Aim: To Plot the resonance curve of a given parallel tuned circuit.

. Apparatus:

S.No Name of the component Specification Quantity

1. Resistors 10Ω 1
2. Inductance Box 100mH 1
3. Capacitor 0.047µf 1
4. Bread board 1
5. Connecting wires 1 Bunch
6. Function generator 1
7. CRO 1
THEORY:
parallel resonance circuit is influenced by the currents flowing through each parallel branch
within the parallel LC tank circuit. A tank circuit is a parallel combination of L and C that is used in
filter networks to either select or reject AC frequencies.
A parallel circuit containing a resistance, R, an inductance, L and a capacitance, C will produce
a parallel resonance (also called anti-resonance) circuit when the resultant current through the parallel
combination is in phase with the supply voltage. At resonance there will be a large circulating current
between the inductor and the capacitor due to the energy of the oscillations, then parallel circuits
produce current resonance.

Resonance occurs when XL = XC and the imaginary parts of Y become zero. Then:

INDUR Institute of Engineering & Technology Dept.ECE 88

 Dept. of Electronics & Communication Engg.

Circuit Diagrams:

PROCEDURE:

1. Connect sine wave generator at the input of the filter. Adjust sine wave
amplitude to 5Volt p-p. Keep the input voltage constant throughout the
experiment.
2. Connect CRO at the output of the filter.
3. Vary the input frequency from minimum to 1KHz in proper steps in sine wave
generator and every time note the input frequency and corresponding output
voltage from the CRO in the observation table.
4. Plot the graph between input frequency & Output Voltage taking input
frequency (in Hz) on x-axis and output voltage (in Volts) on y- axis on semi log
graph paper.
5. Calculate the cut-off frequency from the formula as well as from the graph.
INDUR Institute of Engineering & Technology Dept.ECE 89
 Dept. of Electronics & Communication Engg.

OBSERVATIONS

OBSERVATION TABLE:

S.No. Input Output

frequency Voltage
(in Hz) (in
Volts)
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.

Model graph:

PRECAUTIONS
 Voltage control knob of RPS should be kept at minimum position.
 Current control knob of RPS should be kept at maximum position
 Avoid making loose connections.
 Reading should be taken carefully without parallax error.
Avoid series connection of voltmeters and parallel connection of ammeters.

TROUBLE SHOOTING:
1. Check the probe connection
2. Check the battery connections .Measure V and I with the CRO

INDUR Institute of Engineering & Technology Dept.ECE 90

 Dept. of Electronics & Communication Engg.

RESULTS / CONCLUSIONS

RESULT: frequency response of parallel resonance circuit is verified.

APPLICATIONS
1. These are used in the loud speakers to reduce the low level noise.
2. Eliminates rumble distortions in audio applications so these are also called are treble boost
filters.
3. These are used in audio amplifiers to amplify the higher frequency signals.
4. These are also used in equalizers.

QUESTIONS
VIVA QUESTIONS
1.What is a const. k filter ?
2.ZOT=?
3.Z1Z2=?
4.Is/IR=?
5.Make T & π sections ?
6.Relation between ZOT & ZOπ ?

INDUR Institute of Engineering & Technology Dept.ECE 91