ABSTRACT

Natural Disasters or Natural Calamities, whatever you name it has for long been the most dreaded cause of mass destruction and loss of human lives, wealth and property. It destroys the beauty of earth, lives of humans and leave behind no traces of existence. It’s so severe in its approach that millions and billions of people and land vanishes and escape into oblivion in just a moment. But nothing fruitful or beneficial could be done as most of the people thought that these disasters are natural and cannot be averted. As they say, “MAN PROPOSES, GOD DISPOSES” so they have lived on with the same thought.But with advancement of Science and Technology and with more research and development more and more Scientists, Engineers and Physicists concluded that although such a calamity cannot be averted but a proper precaution can be taken from it. They said “Where there is a will there is a way” and “Prevention is always better than cure” so with that thought they created an alarming or a warning system which would well beforehand makes the authorities and the people aware of the dangers so that precautionary measures can be taken and there is not much or massive loss of lives and property.A warning system that can well in advance detect and alarm the people of the dangers and give us ample time to relocate ourselves so as to avoid the severity caused by the disaster. It uses sensors, micro controllers and radio frequency so as to transmit and receive signals. With the technology still at its infant stage, a lot of automation needs to be done so as to prepare for a better tomorrow and the need of the hour is to stimulate the best use of growing science and technology. 

TABLE OF CONTENTS

GLOSSARY OF TERMS…………………………………………………………..xii

OBJECTIVE AND   MOTIVATION……………………………………………….xiii                                                                             

LIST OF TABLE ......................................................................................................xiv   

LIST OF FIGURE………………………………………………………………….xv

CHAPTER 1………………………………………………………………………..1

1.i Introduction…………………………………………………………………....2

1.1.Block Diagram…………………………………………………………..3

1.1.1.Transmitter Section……………………………………………….3

1.1.2.Receiver Section………………………………………………….4

1.2. Circuit Diagram……………………………….………………………....5

1.3. Working Approach………………………………………..……………..6

1.3.1.Power Supply Section……...……………………………..….…...6

1.3.2 Transmitter Section……………………………………………….6

1.3.3.Receiver Section………………………………………………….7

1.3.4 Fully Assembled Project………………………………………….7

CHAPTER 2. ………………………………………………….……………….…..8

2. Power Supply…………………………………………………….………...….9

2.1. Transformer…………………………………………………………...….9

2.1.1. Working Principle………………………………………………..10

2.2. Resistor………………………………………………...……………...….14

2.2.1. Resistor Symbol……………………………………....………......15

2.2.2.Carbon Film Resistor………………………………...………..….15

2.2.3. Metal Film Resistor……………...……………….........................17

2.2.4. Non Linear Resistor……………………………....……………....17

2.2.5. Resistor Marking…………………………………………………18

2.3. Variable Resistor………………………………………...…..………...…20

2.3.1.Description…………………………………….……..…………...20

2.4. Capacitor…………………………………...………………………..……21

2.4.1. Block Capacitor (Fixed Value) ………………………….……….22

2.4.2. Electrolytic Capacitors…………………………………...……….23

2.4.3. Ceramic Capacitors……………………………………….………24

2.4.4. Multi layer Ceramic Capacitors…………………………...........…24

2.5.  Bridge Rectifier…………………………………………………...…..…..25

2.5.1. Current flowing In Bridge Rectifier…..…………………………..26

2.6.  Diode……………………………………………………………………...27

2.6.1. Rectification/Switching/Regulation……………………..………..30

2.7.  Light Emitting Diode…………………………………………….……….32

2.8. Diode Marking……………………………………………………………33

2.9.  Voltage Regulator………………………………………………………...34

2.9.1. Features…………………………………………………………...34

2.9.2. Internal Block diagram……………………………………………35

CHAPTER 3. …………………………………………………,,………………...…38

3.  Transmitter Section……………………………................................................38

3.1.  Transistor……………………………………….......................................39

3.1.1.Type of Transistor………………………………………………..39

3.1.1.1.BJT……………………………………….....39

3.1.1.2. FET………………………………………….41

3.2.Encoder……………...…...........................................................................44

3.2.1.   Features…………………………………………………………..44

3.2.2.   Applications……………………………………………………...45

3.2.3.   General Description……………………………………………...45

3.2.4.   Block Diagram…………………………………………………...46

3.2.5.   Pin Assignment…………………………………………………..46

3.3.   RF Transmitter…………………………………………...…....................47

3.3.1.  Overview………………………….………………...…..................47

3.3.2.  Features………….……………...…….….………………………..47

3.3.3.  Applications……………….………………...……….....................48

3.4.   Sensors…………………….………………...……...……………………..48

3.4.1.  Water Level Sensor…….………………………...………………..48

3.4.2.  Piezo electric Sensor…………………………….………………....48

3.4.2.1. Principle Of Operation……………………...49

3.4.2.1.1. Transverse Effect…………………...49

3.4.2.1.2. Longitudinal Effect…………………49

3.4.2.2. Electrical Properties………………………...50

3.4.2.3. Sensor Design………………………………51

3.4.2.4. Sensing Materials…………………………...52