1. A
MINI PROJECT REPORT
ON
CLAP SWITCH
BY
PARTH.S.CHOLERA
Department of Electronics and Tele-communication
2011-12
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2. CERTIFICATE
This is to certify that, the project entitled CLAP SWITCH a
bonified record of project work submitted by
PARTH.S.CHOLERA in partial fulfillment for degree in
EXTC, Mumbai University during the year 2011-2012 under
my guidance and supervision.
DATE:
PLACE: Thane
GUIDE HEAD OF DEPARTMENT
(Prof.Pawar) (Prof. A.M.Deshpande)
External Examiner Principal
(Dr.U.D.Kolekar)
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3. ACKNOWLEDGEMENT
It is my great pleasure to acknowledge the assistance and
contribution of the individuals who co-operated us to complete
the project work successfully. First and foremost, I wish to
express my deep gratitude and thanks to Prof.A.M.Deshpande
Head of department of EXTC and our project guide Prof.Pawar,
for their enthusiastic guidance and helping in successful
completion of project work. They provided us their precious
time for valuable suggestions and encouragement throughout the
work. It is foe their patience, guidance and encouragement at all
time that this work has shaped up the way it is.
A project is teamwork and reflects the contribution of many
people. A number people contributed their time and efforts in
making their project work a success. We would like to thank
everyone who contributed their time and efforts to help in
completing the project work.
PARTH.S.CHOLERA
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4. TABLE OF CONTENTS
Sr. No. Topic Page no.
1. Introduction 5
2 Block Diagram 6
3. Circuit Diagram 6
4. Working of Circuit 7
5. Component List 8
6. Advantage & Disadvantage 9
7. Application 10
8. Further Modification 10
9. Bibliography 11
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5. INTRODUCTION
This is a project on CLAP SWITCH which can switch
on/off any electrical circuit by the sound of the clap.
The basic idea of clap switch is that the electric
microphone picks up the sound of your claps, coughs, and the
sound of that book knocked off the table. It produces a small
electrical signal which is amplified by the succeeding transistor
stage. Two transistors cross connected as a bistable
multivibrator change state at each signal. One of these
transistors drives a heavier transistor which controls a lamp.
This circuit is constructed using basic electronic
components like resistors, transistors, relay, transformer,
capacitors. This circuit turns ‘ON’ light for the first clap. The
light turns ON till the next clap. For the next clap the light turns
OFF. This circuit works with 12V voltage .Therefore a step-
down transformer 12V/300mA is employed.
This working of this circuit is based on amplifying nature
of the transistor, switching nature of transistor, relay as an
electronic switch .Basically, this is a Sound operated switch.
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6. CIRCUIT DIAGRAM
BLOCK DIAGRAM
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7. WORKING PRINCIPLE
The sound of clap is received by a small microphone that
is shown biased by resistor R1 in the circuit. The microphone
changes sound wave in to electrical wave which is further
amplified by Q1.Transistor Q1 is used as common emitter
circuit to amplify weak signals received by the microphone.
Amplified output from the collector of transistor Q1 is then feed
to the Bistable Multivibrator circuit also known as flip-flop.
Flip flop circuit is made by using 2 Transistor, in our
circuit Q2&Q3. In a flip-flop circuit, at a time only one
transistor conduct and other cut off and when it gets a trigger
pulse from outside source then first transistor is cutoff and 2nd
transistor conducts. Thus output of transistor is either logic-0 or
logic-1 and it remains in one state 0 or 1 until it gets trigger
pulse from outer source.
The pulse of clap which is a trigger for flip-flop which
makes changes to the output which is complementary (reverse).
Output of flip-flop which is in the low current form is unable to
drive relay directly so we have used a current amplifier circuit
by using Q4 which is a common emitter circuit. Output of Q4 is
connected to a Relay (Electromagnetic switch), works like a
mechanical switch. With the help of a relay it is easy for
connecting other electrical appliance.
The relay contact is connected to the power line and hence
turns on/off any electrical appliance connected all the way
through relay.
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8. COMPONENT LIST
Resistors
R1= 15KΩ,
R5, R6= 1.5KΩ
R2, R11, R12= 2.2MΩ,
R13= 2.2KΩ
R3= 270KΩ,
R4= 3.3KΩ
R7, R8= 10KΩ,
R9, R10= 27KΩ
Capacitors
C1=1000µf/16v
C2=.01µf,
C3, C4=.047µf
Semiconductor
Q1, Q2, Q3= BC548
Q4= BC368
D2, D3, D4= IN 4148
D1, D5= IN 4007,
Misc
T1= 12v/500mA Transformer
Mic= Condenser Microphone
K1= 12V Relay, B1= Bulb or Load
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9. ADVANTAGE
It’s used to turn something (e.g. a lamp) on and off from
any location in the room (e.g. while lying in bed) simply by
clapping your hands.
It involves an elderly.
Also involves mobility-impaired person.
It’s also used for a light, television, radio, or similar
electronic device that the person will want to turn on/off
from bed.
DISADVANTAGE
It cumbersome to have to clap one's hands to turn
something ON or OFF
Also, generally seen as simpler for most use cases to use a
traditional light switch.
Unnecessary disturbances may occur while using in the
Apartments
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10. FUTURE SCOPE
We can increase the range of this equipment by using better
Mic.
We can use this as Remote Controller.
APPLICATIONS
Clap switch can be used to switch ON/OFF any electrical
appliances such as
Tube Light,
Fan,
Television,
Air conditioner,
Motor, etc.
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11. BIBLOGRAPHY
http://wiki.answers.com/Q/What_are_the_advantages_disa
dvantages_and_applications_of_a_clap_switch#ixzz1cOqY
8QQX
The on-line textbook : Information Theroy, Interference,
and Learning Algorithms,
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