This slide tells about how we operate the electrical instruments using the sound energy, as example given as a notice board operated using the clap sound.

1. Clap Operated
Notice Board
National Institute of Technology
Meghalaya
By Abu Bakker Siddik & Ajeet Kumar Singh
Under the Guidance of Dr. Kamalika Datta

2. Index
 Introduction
 Motivation
 Working principle
 Block diagram
 Circuit diagram
 Code
 Practical
 Advantages & Applications
 Implementation
 References

3. Introduction
What is a clap operated circuit?
 A clap operated circuit is one which switches on and off
electrical appliances with sound of clapping hands.
 Any electrical appliance such as a fan, light, music system etc.
has can be operated using this circuit.

4. Introduction cont…
 It uses an electret microphone as a transducer for converting a
clapping sound into an electrical signal.
 It based on sound sensor which detects sounds from the
environment and processes the sound with the help of
Microcontroller and performs appropriate tasks as desired.

5. Motivation
 Why do we require a sound sensing circuitry?

6. Working Principle
 The clap switch requires a transducer at the input to convert
sound vibrations from clapping hands into electrical energy.
 An electric microphone or simply mic is used for this purpose.
 The output from the mic is very low in magnitude and so we
need an amplifier circuit to boost the detected sound signal.

7. Block Diagram
Transducer(Mic) Amplifier Circuit Microcontroller
STEP 1
The transducer(Mic) takes input from the environment and converts the energy(in our case)
to electrical signal which is low in magnitude.
STEP2
Amplifier amplifies the low magnitude electrical signal from the Transducer.
STEP3
The Microcontroller further processes this amplified electrical signal.

8. Circuit Diagram
Vout

9. Code

10. Practical

11. Advantages & Application
 Prevention from “electric shock”
 Can be implemented to ease access for physically disabled
people
 Can be used for detecting trespassers and initiate a security
lockdown protocol
 Can be implemented in a “Notice Board”, particularly in digital
notice boards

12. Implementation
 The Clapper is a sound
activated electrical switch
,sold by San Francisco,
California based Joseph
Enterprises, Inc

13. References
 Videos:
 https://www.youtube.com/watch?v=mgQLSAtS-zQ
 https://www.youtube.com/watch?v=5d3468IZKtk
 Other references:
 Wikipedia
 http://embedded-lab.com/blog/?p=6439

14. Thank You
for your Attention