Physics

clap switch Topic-

{ Converts the sound

signal into electrical energy }

HEPHZIBA VARGHESE X11 - D

NO 1

TOPIC AIM

PG NO.

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ACKNOWLEDGEMENT

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INTRODUCTION

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MATERIALS REQUIRED

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BASIC PRINCIPLE

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BLOCK DIAGRAM

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CIRCUIT COMPENANTS

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PROCEDURE

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OBSERVATION

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PRECAUTIONS

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CONCLUSION

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BIBLIOGRAPHY

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To prepare a clap switch, that converts a sound signal into electrical energy.

I would like to express my sincere gratitude to my chemistry teacher Mr. jeneesh joseph , for his vital support guidance and encouragement without which this project would not have come forth.

INTRODUCTION This is a circuit that can be used to turn a device on and off by sound only, hand clapping, whistling etc. the basic idea of clap switch is that the electrical microphone picks up the sound of your claps, coughs and the sound of of that book knocked off the table. The operation of the circuit is simple. If we clap the lamp turns on and to switch it off clap again . It produces a small electrical signal which is amplified by the succeeding transistor stage. Two transistors cross connected as a bi-stable multi vibrator change state at each signal. One of these transistors drives a heavier transistor which controls a lamp. This circuit can switch on and off a light, a fan or radio etc by the sound of a clap

When triggered, the circuit will stay in the on or off condition till it is triggered again. This circuit is constructed using basic electronic components like resistors, battery condenser mic , led, 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. It is generally used for light, television, radio or similar electronic device that the person can turn on or off even without going close to it.

The basic principle of this clap switch circuit is that it converts sound signal into electrical energy. The input component is a transducer that receives clap sound as input and converts it to electrical pulse. 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. transistors cross connected as a bi-stable multi vibrator change state at each signal. One of these transistors drives a heavier

transistor which controls a lamp. when we clap our hands , the sound is received by by AUDIO AMPLIFIER. Here the given sound signal is converted into electrical signal and then amplified by using transistors. Here through the circuit we make we shall glow a led.

BLOCK DIAGRAM

Circuit COMPONENTS RESISTORSResistors are the most common passive electronic component (one that does notrequire power to operate). They are used to control voltages and currents. While a resistor is avery basic component, there are many ways to manufacture them. Each style has its owncharacteristics that make it desirable in certain types of applications. Choosing the right type ofresistor is important to making high-performance or precision circuits work well. This bonus chaptercovers the resistor types and helps with picking the right one for your project. All resistors are basically just a piece of conducting material with a specific value of resistance. For that piece of conducting material to be made into a practical resistor, a pair of electrodes and leads are attached so current can flow. The resistor is then coated with an insulating material to protect the conducting material from the surrounding environment and vice versa. There are several different resistor construction methods and body styles (or packages) that are designed for a certain range of applied

voltage, power dissipation, or other considerations. The construction of the resistor can affect its performance at high frequencies where it may act like a small inductor or capacitor has been added, called parasitic inductance or capacitance.The resistors used here is 1k , 4.7 k and 470 ohm.

CAPACITORS Capacitor has ability to store charge and releasethem at a later time. Capacitance is the measure of theamount of charge that a capacitor can store for a givenapplied voltage. The unit of capacitance is the farad (F) ormicrofarad. The capacitors used in the circuit areelectrolyticcapacitor.In the circuit the electrolytic capacitor is used as a bypass capacitor. Any noise variation inthe circuit is removed by the capacitor. 100uf is used here

BATTERY In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery (or "voltaic pile") in 1800 by Alessandro Volta and especially since the technically improved Daniel cell in 1836, batteries have become a common power source for many household and industrial applications. According to a 2005 estimate, the worldwide battery a industry generates US$48 billion in sales each year, with 6% annual growth There are two types of batteries: primary batteries (disposable batteries), which aredesigned to be used once and discarded, and secondary batteries (rechargeable batteries),which are designed to be recharged and used multiple times. Batteries come in many sizes,from miniature cells used to power hearing aids and wristwatches to battery banks the size ofrooms that provide standby power for telephone exchanges and computer data centres.

TRANSISTORA transistor is a semiconductor device used to amplify and switch electronic signalsand

electrical power. It is composed of semiconductor material with at least three terminalsfor connection to an external circuit. A voltage or current applied to one pair of thetransistors terminals changes the current flowing through another pair of terminals. Becausethe controlled (output) power can be higher than the controlling (input) power, a transistorcan amplify a signal. Today, some transistors are packaged individually, but many more arefound embedded in integrated circuits ic An integrated circuit (IC), sometimes called a chip or microchip, is a semiconductor wafer on which thousands or millions of tiny resistors, capacitors, and transistors are fabricated. An IC can function as an amplifier, oscillator, timer, counter, computer memory, or microprocessor. A particular IC is categorized as either linear (analog) or digital, depending on its intended application LEDA light-emitting diode (LED) is a twolead semiconductor light source. It is a basic pnjunction diode, which emits light when activated.[7] When a suitablevoltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor

PROCEDURE Connect all the components as shown in the figure. First place the resistor of 4.7k resistance and then of 1k and then 2 resistors of 47o ohm and 47 k and the place 2 transistor of BC547AND CAPACITOR OF 1oonf. After this place an led bulb. Capacitor of 1oomf.condensor mic and a battery cap. And then to give current to the circuit place a battery of volt 9.

Now we shall place all these in this pcB board after drawing this diagram on while placing a capacitor of 1oomf which has two terminals the bigger one is positive and the smaller is negative. the big one will come towards the end side.

Now we will place a condenser mic. which has two terminals .in which the bigger one is positive and he smaller one is negative. The positive terminal will come towards the upper side. Led has two terminals the bigger one is positive and the smaller one is negative. The bigger one will come to the upper side. After placing a 470 0hm resistance, we will place an 555 IC In which the cutted end will be towards the left. After placing all these we shall do the soldering but before that we will remove the condenser mic. We shall join the 2nd wire of transistor to the resistance wire 4.7 k . now join the resistance R1 wire t o the first wire of the transistor. Resistors r 2 wire to the first wire of transistor t2. Now join the capacitor wire to the two wires of t2 and r2.now r3 wire to the capacitor wire. Transistor wire to third wire of ic.resistancer4 wire to 7th wire of IC. Now solder the 6th and 7th wire of IC. Now join ICs 2nd wire to the capacitors wire c1. Now join c3 1oonf to ICs 5th wire. Now join ICs 8th wire to its 4th wire and this 4th and 8th wire should be joined to the resistance Rs 47 k.

Now place the condenser mic.

Join the condensers wire to the wire of resistance.r1 4.7k. now we will place one wire to the negative side of battery cap which will be attached to the positive side of mic to the ik and r2 470 0hm and to 47 k and to 4.7 k.and join rs 4.7k and t1BC 547 and this should be joined to rs 470 ohm.Now we shall place another wire at the corner side which will be then attached to the rs 4.7k and then to the two transistorsT1 and T2 and then to capacitor c2 and then to capacitor c1

Now we shall join the ic wire to the wire given below. (Negative

terminal wire)

Then to this wire we will join the wire of led. Now the battery cap, as it has two terminal red and black colored. In which the red is positive and the black 0one is negative. The red i.e. Positive will come towards the upper side and negative i.e. The black one will and black towards the bottom

now we shall place a 9 volt battery to it. As soon as we place a

battery as the circuit gets complete and as we clap the bulb glows. we can check this once again by removing the battery and placing it again.

ADVANTAGES 1. The primary application involves an elderly or mobility-impaired person. 2. We can turn something (e.g. a lamp) on and off from any location in the room (e.g. while lying in the bed) simply by clapping our hands. 3. Low cost and reliable circuit. 4. Complete elimination of man power .5. Energy

efficient

FUTURE SCOPE We can increase the range of this equipment by using better Mic.

We can use this as Remote Controller.

DISADVATAGES 1. It is generally cumbersome to have to clap one’s hands to turn something on or off and it is generally seen as simpler for most use cases to use a traditional light switch.

2. Unless we use a filter in the circuit , it is not that advantageous. So that circuit activates only for clap of particular frequencies and then it becomes accurate.

APPLICATIONS 1. Clap activated switch device will serve well in different phono-

controlled applications. 2. Clap switch is generally used for a light, television, radio or similar electronic device that the person will want to turn on/off from bed. 3. This circuit functions on using the sound energy provided by the clap which is converted into electrical energy by condenser microphone . Using this converted electrical energy which is used to turn on relay (an electronic switch). 4. The primary application involves an elderly or mobility-impaired person. 5. The major advantage of a clap switch is that you can turn something (e.g. a lamp) on and off from any location in the room(e.g. while ON bed)simply by clapping your hands.

6. The major disadvantage is that its generally cumbersome to have to clap ones hands to turn something on or off and its generally seen as simpler for most use cases to use a traditional light switch.

THE BULB GLOWS AS SOON AS THE CIRCUIT GETS COMPLETE AND A CLAP SOUND IS GIVEN.

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 The mic should be removed before soldering is started.  components in the circuit should be as instructed.  Unnecessary disturbances should not be there while giving the first clap.

The clap activated switching device function properly by responding to both hand claps at about three to four meter away and finger tap sound at very close range, since both are low frequency sounds and produce the same pulse wave features. The resulting device is realizable, has good reliability and it’s relatively inexpensive. Assemble the circuit on a general-purpose PCB and enclose it in a suitable box. This circuit is very useful in field of electronic circuits. By using some modification it area of application can be extended in various fields. It can be used to raised alarm in security system with a noise ,and also used at the place where silence needed.

We constructed the circuit as per circuit diagram . And we verified the clap switch circuit. i.e when sound occurs near by the circuit the led in the circuit glows and for the second clap in off condition.

BIBLIOGRAPHY

Websites : http://www.sciencedirect.com

http://www.helpguide.org/

http://wwwlibrarythinkquest.org/ BOOKS REFFERED

Class xii physics laboratory manual