ABSTRACT
The
main objective of this project was to ensure a proper security to car being
parked in garage against theft or an intruder. The
circuit uses three NE555 timers; one of the NE555 was wired as a monostable
oscillator and remaining two were wired as tone generator and amplified to
obtain a maximum audible sound. However, pin 2 of the first NE555 was used as
sensor part .When pin 2 has contact with human body or hand it will activate
the IC1 which will also bias transistor and this transistor was wired in a way
that once it is powered it will close
circuit thereby passing a negative supply voltage to tone generator circuit
and outputted out through a loud speaker or buzzer.
This device functions as a major
security device against car-theft as stated above. It is an electronic device
that is connected to the battery of the car it is being installed in and gets
activated when the car engine is switched off and the car stationed at a place.
The device is not seen but, it has an indicator light which shows that the
alarm has been activated. When the body of the car is touched by human hand, it
sends a negative signal to the device which needs a negative pulse to get
activated; it sends this negative from the human hand to the tone generator IC
which triggers the alarm.
TABLE OF CONTENT
Title Page ...…………………………………………………………………….i
Certification…………………………………………………………………….ii
Dedication ……………………………………………………………………...iii
Acknowledgement …………………………………………………………….. iv
Abstract ………………………………………………………………………….v
Table of content ………………………………………………………………...vi
List of Symbols ………………………………………………………………. vii
CHAPTER ONE:
Introduction 1.1 Background of
study…………………………………………………… 1
1.2 Aims
and objectives…………………………………………………… 3
CHAPTER
TWO: Literature Review……………………………………….4
CHAPTER
THREE: Specification and operation of system component 3.1 Description of NE55 Timer…………………………………………….12
3.2 Description
of Resistor………………………………………………. 14
3.3 Description
of Capacitor…………………………………………….. 16
3.4 Description
of Diode………………………………………………… 27
3.5 Description
of Transformer …………………………………………… 32
3.6 Description
of Loud Speaker and Buzzer……………………………… 41
3.7 Description
of Transistor………………………………………………. 43
3. 8 Description of L.E.D…………………………………………………..
47
CHAPTER
FOUR: Operation of system and its circuit and block diagram
4.1 Operation
of circuit ………………………………………………… …55
4.2 The
circuit diagram………………………………………………….. ..57
4.3 The
block diagram………………………………………………………58
CHAPTER
FIVE: Construction, Testing and Packaging
5.1 Values
of components………………………………………………….59
5.2
Assembly………………………………………………………………60
5.3 A
schematic diagram of the finished work…………………………….63
CHAPTER
SIX: Conclusion and Recommendation
6.1 Conclusion
………………………………………………………….. .64
6.2 Recommendation
…………………………………. …. ……… .….65
6.3 Observations
………………………………………………………..66
6.4 Dificulties……………………………………………………..
…57
6.5 References…………………………………………………. …………68
LIST
OF SYMBOLS
NAME SYMBOLS
Resistor
|
Transistor
Diode 
Zener diode 
Trimmer capacitor 
Polarized capacitor 
Unpolarized capacitor 
 |
Variable capacitor
CHAPTER
ONE: INTRODUCTION
1.1.
Background
of the Study
The first car alarm was a primitive
contraption that utilized a bell or horn connected to the drive shaft. It was
created by an unnamed Nebraska inventor in June 20th, 1920. It
utilizes the drive shaft to operate its own bell or horn signal when the car is
properly moved. This is just a little talk on a car alarm but not a car touch
intruder alarm which is a modern, more advanced, and more reliable type of car
alarm.
This car touch sensitive alarm project
consist of three NE555 timer IC, the first NE555 was wired as monostable multi-vibrator and the remaining two were
wired as tone generator. When the sensor is touch or
has contact with human hand perhaps body, IC1 is triggered at its pin 2 and
output pin 3 goes high for a time period previously set by the values of R4
(10M) and Q1 (transistor) was bias via R3 and this transistor is in such a way
that once it was biased it will supply a negative voltage to tone generator
thereby making two NE555 timer which was know as (tone generator) to oscillate
to make a bell sound through the buzzer. The tone generators are configured as
an astable multi-vibrator whose oscillation frequency can be varied with the
help of PR1 and PR2. By adjusting the values of PR1 and PR2, modifications on
the tone are possible.
The reset button is
used to set or open circuit the system back to its initial stage. The system is
powered with 12V power supply voltage.
The first chapter of this
project is narrating on the introduction, the concept of the system and also
the aims and objective. Chapter two is all about literature review. Chapter three
talks about specification and operation of system component. Chapter four is
operation of system. Chapter five is about construction, testing and packaging.
Chapter six is conclusion, observation, recommendation and References.
1.2 AIM AND OBJECTIVE
The main aim and objective of the design
and construction this project is to create a comfort in the minds of vehicle
owners or users when their vehicles are parked or stationed anywhere without
much fear of car-theft.
