Exp no 1 edited Analog electronics

Clipper Circuits
SUBJECT : ANALOG ELECTRONICS
JULY 11, 2017
ojrane@mitaoe.ac.in
Batch B1 Bock 1
Omkar Rane SETB118
Rohit Mane SETB102
Abhishek Sainkar SETB104
Tanmay Kale SETB112

S.Y.B. Tech (ET): 2017-18 Analog Electronics
Post Lab. Questions: -
1. Illustrate limiter circuit with other application.
Ans 1) An FM radio receiver usually has at least one stage of
amplification for this purpose. It provides a constant level of signal to the
FM demodulator stage, reducing the effect of signal level changes in the
output. If two or more signals are received at the same time, a high-
performance limiter stage can greatly reduce the effect of the weaker
signals on the output.
2. Compare clipper & clamper circuit with example.
Ans 2) CLIPPING CIRCUIT:
1) Diode Clipper is a wave shaping circuit that takes an input
waveform and clips or cuts off its top half, bottom half or both
halves together. This clipping of the input signal produces an
output waveform that resembles a flattened version of the input.
2) It is also known as a limiter
CLAMPING CIRCUIT:
3) The Clamping circuit or clamper keeps the amplitude of the output
signal same as that of the input signal except that the D.C.
level (offset) has been changed.
4) Simply it is a circuit that places either the positive or
negative peak of a signal at a desired d.c. level is known as a
clamping circuit.
5) The shape of the waveform will be the same, but
its level is shifted either upward or downward.
6) There will be no change in the peak-to-peak or rms value of the
waveform.
7) The values of the resistor R and capacitor C affect the waveform
and are determined from the time constant RC. (t = RC)
8) In a good clamper circuit, the circuit time constant should be at
least ten times the time period of the input signal voltage so that

the voltage across the capacitor C does not change significantly
during the time interval the diode is non-conducting.
3. List different applications of diode in Electronic circuit & explain
any one in details
Ans 3) some of the typical applications of diodes include:
1)Rectifying a voltage, such as turning AC into DC voltages
2)Isolating signals from a supply
3)Voltage Reference
4)Controlling the size of a signal
5)Mixing signals
6)Detection signals
7)Lighting
8)Lasers diodes
9) Over voltage protection
Over-Voltage Protections
Diodes also function well as protection devices for sensitive electronic
components. When used as voltage protection devices, the diodes are
non-conducting under normal operating conditions but immediately
short any high voltage spike to ground where it cannot harm an
integrated circuit. Specialized diodes called transient voltage suppressors
are designed specifically for over-voltage protection and can handle very
large power spikes for short time periods, typical characteristics of a
voltage spike or electric shock, which would normally damage
components and shorten the life of an electronic product.

EXPERIMENT No: 1
Limiter in FM Transmitter
Introduction: -
Limiters are the circuits that employ diodes to remove a portion of an
input signal without distorting the remaining part of the applied
waveform. A limiter is a clipper that can serve as a protective measure,
preventing a signal from exceeding the clip limits.
A practical application of a limiter or clipper is to prevent an amplified
speech signal from overdriving a radio transmitter. Over driving the
transmitter generates spurious radio signals which cause interference
with other stations.
Reference: http://www.allaboutcircuits.com/vol_3/chpt_3/6.html
Fig. a. Clipper in FM transmitter
Reference: https://www.arrl.org/files/file/Get%20Licensed/8505023.pdf
Fig. b. Circuit for audio channel that might be used in FM transmitter

To obtain maximum effectiveness from our FM signal, we must ensure
that ample audio is available. Te average audio level may be increased
by, means of clipping. This will give FM signal more apparent volume at
the receiver.
The audio energy from microphone is amplified and passed to the speech
limiter where the positive and negative peaks of the audio sine wave are
squared and clipped. This clipped signal is then passed through the filter
before applying it to transmitter.
Post Lab. Question: -
Identify the clipper circuit in the figure b.
(series as well as there are parallel clippers)
Objective: -
 To identify role of limiter circuit in FM transmitter.
 To design and test the limiter circuit
2. List the Equipments / Component required for the experiment
Equipment / Components Specifications/Values
Haltech-plus CRO HT 4030 30Mhz
(Oscilloscope)
30Mhz
Digital Multimeter AC 230 volts, AC, DC
Caddo 4061 Digital Signal
Generator
Caddo 3 MHz pulse signal generator
40 MHz frequency counter.
General Purpose diode 2 max
resistors 1
Connecting wires As per requirements
Regulated DC Power supply
Bread Board 1
Oscilloscope probes Two ways BNC, One way
Operational Amplifier IC 741
3. Test component using CRO & DMM & Write test Report.
Component Tools for testing Status

diode CRO/DMM functioning
resistance DMM functioning
wires DMM functioning
CRO Probe testing functioning
CRO probe See 2V p-p values in
square wave
functioning
Bread board DMM functioning
4. Describe Process of experiment in steps.
Step1) With the help of multisim version 8 software just simulate all
clipper circuit.
Step 2) Check all probes and electronics components, breadboard in
working condition.
Step2) after getting proper wave forms and desired output voltages go for
actual hardware testing of clipper circuits.
Step 3) Make proper use of signal generator for giving Vi (Input voltage),
Vo (output voltage) to be seen on CRO.
Step 4) Make Use external DC regulated supply in dual clipper or parallel
clipper circuits.
Procedure: -
i)Initially test the probes to ensure whether it is properly working.
ii)Connect one end of two-sided (BNC) probe to the function generator
and other end to the CRO.
iii)Now set the Output Voltage through Function Generator using CRO.
[Vin = 5 volts]
iv)Now assemble the components properly according to the circuit
diagram on the breadboard.
v)Now supply input voltage through Function Generator to Vin.
vi)Supply DC voltage in series to each Diode so as to get a proper
required clipped voltage. (In Biased Clipper Circuits only)

vii)Connect the output to the CRO so as to get a proper clipped output
waveform.
5. Observation Table:
Parallel /dual Clipper

Parameters Measured Values
Volts/div
(y-axis)
1.2(volt)*(1 volt/div) = 1.2 volt
Time/div
(x-axis)
1(div)*(1*10-3
time/div) =time=
1*10-3
Vi (input voltage) 5 volts
Frequency
F=1/T
1 KHz =1000 Hz
Case 1)
Vi= V
Vi=V=5 volts
Case 2)
Vi<V
V=10.1 volts
Vi=5 volts
Case 3)
Vi>V
Vi=5 volts
V = 2.6 volts
Series Clipper
Parameters Measured Values

Volts/div
(y-axis)
1.4(volt)*(1 volt/div) = 1.4 volt
Time/div
(x-axis)
1.2(div)*(0.5*10-3
time/div) = time=
0.6*10-3
Vi (input voltage) 5 volts (given P-P by signal
generator)
Frequency 1 KHz =1000 Hz
Types of Circuits Studied:
1)Biased clippers (With Battery): Parallel and Series,
2)Unbiased Clippers (Without Battery): Parallel and series,
3)Dual Clipper circuit
Unbiased Series positive clipper on multisim

Unbiased Series Negative clipper on multisim:
Parallel clipper or both side/dual clipper

Multisim.

Unbiased Series Positive Clipper Circuit:
Positive
Circuit

Comparison with input signal and output wave form.
Comparison with Input voltage and Output voltage signal
Unbiased Series Negative Clipper:
Unbiased Parallel/ Dual Clipper:

Clipping of wave-form can be seen from both side
Circuit of parallel clipper.
Biased Parallel /Dual Clipper without external

supply:
Biased Parallel /Dual Clipper with external
supply:
Vi=5v from signal generator.
External DC source V= 5.3v
V=Vi

Parallel /Dual Clipper with external supply:
Vi= 5v from signal generator, V=2.6v from external DC power supply.
Vi>V
Vi= 5v from signal generator, V=10.1v from external DC power supply.
Vi<V

Parallel /Dual Clipper with external supply:
Circuit
Conclusion: -
We have gone through different types of clipper circuits like series, parallel, dual
clippers
Each clipper circuit has its own characteristics to clip off positive, negative or both
Forms of wave. We also verified clipper circuit through operational amplifier
circuit.
Parallel clipper with biasing or unbaising was also seen.

Exp no 1 edited Analog electronics

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Exp no 1 edited Analog electronics

Similar to Exp no 1 edited Analog electronics (20)

More from Omkar Rane

More from Omkar Rane (20)

Recently uploaded

Recently uploaded (20)

Exp no 1 edited Analog electronics