Sound of a Clap Switchs the project OFF or ON. This can be attached with bulb, light, fan to switch OFF or ON. It works as a remote switch. This can also be utilized as night bed switch and as a bugler alarm.
TECHNICAL DESCRIIPTION AND WORKING:-
This project has been developed and successfully tested OK in TV Engineer Technical Lab.
This project is not a magic but works likes a magic. A clap sound operates the switch either OFF or ON. This project is useful for the people who want to operate [OFF/ON] fan, light, Radio, TV etc. sitting on a chair.
In this project, a condenser microphone receives the sound a clap. The condensor microphone is in series with R1 15K. The microphone picks of the sound and converts sound energy into electrical energy. The power of this electrical energy is very low to operate the relay. Therefore this energy is fed to Q1 BC149, Q2 BC149, Q3BC149 to amplify. These Transistors amplify the signal and enhance the energy.
This amplified wave is fed to output transistor Q4 BC149 & relay. When the clap sound is produced R4 conduct and relay connected to collector of transistor Q4 operate. Due to megnetic effect, the relay changes its position. Here Relay works as a switch which become of ON/OFF a clap and becomes ON with another clap. This project utilises 12V DC which is available through step down transformer.
NOTE:- This circuit becomes OFF or ON when there is sound of claps.
PRECAUTIONS WHILE ASSEMBLING THE PROJECT:-
- Check all the compoents as per circuit specification
- Check primary and secondary winding of Transformer. If Primary is alterted with secondary, it will damage all the components.
- Check anode & cathode of diodes [D2, D3, D4, D5] [IN4148] before mounting.
- Check anode & cathode of diode D1 IN4002 & mount correctly.
- While mounting transistor Q1, Q2, Q3, Q4 connect collector, base & emitter correctly.
LIST OF COMPONENTS
R1 15K – 1
R2, R5, R12, 1M2 – 3
R3 270K – 1
R4 3K3 – 1
R6, R10 27K – 2
R7, R11 1K5 – 2
R8, R9 10K – 2
R13 2K2 – 1
C1 .01  – 1
C2, C3 .04 – 2
C4 1000MFD/16V – 1
Q1, Q2, Q3, Q4 BC149B – 4
D1 IN4002 – 1
D2,D3,D4,D5 IN4148 – 4
CONDENSOR MICROPHONE – 1
TRANSFORMER X1 12VOLT/300E
RELAY 12V [SINGLE CHANGE OVER RELAY]
FLEXIBLE WIRE AS REQUIRED
PCB – 1