DESIGN AND CONSTRUCTION OF SECURITY BEEPER
This project report is a thesis written specifically to cover the design analysis construction, test and packaging of a multipurpose security system from electric component that can be easily be obtainable from the market.
The report discusses the various unit and stages of the alarm system, thesis include:-
a) Clock generation and frequency division unit.b) The control and section unit, comprising of a one shot 555 timer multiplexer, sound amplifier and the latch.c) The detection and switching unit made up of the fire and burgler sensors and priority encoder.d) The output unit comprising of the visual display and audio systems. These units have been lucidly represented with block diagrams and the calculations and the analysis of each component in the circuit of each block were done in the subsequent chapters of this part.
However, my own project is designed to serve three purposes: to detect human touch, burglar operation and to detect fire, giving the corresponding alarms and indications.
In a situation where there is a need to monitor the movement of people in a confidential building or a restricted area or to alert security-men in the case of fire outbreak, multipurpose security system is an electronic gadget which detect human shadow, human touch and fire and alert security-men through an alarm and equally display the particular room or area in which the target was hit.
The multi-purpose security system uses Light Dependent Resistor (LDR) to sense human shadow, touch switch to sense human touch and thermistor to sense fire.
The circuit is enclosed in such a way that if he sensor are installed in each various room, say room 1,2 and 3 etc. If an intruder wants to break through, say room 2 once he touches the handle of the door, the touch sensor senses his touch, then triggers an alarm and display room 2 on a big display board.
If to say, there is fire outbreak in the same room 2 the fire sensor will sense it, trigger an alarm and equally display room 2. This is also application to all the room that has the sensor.
Multipurpose security system can equally be applied in banks, industries, financial institutions, schools and home to help safeguard lives and property.
LIST OF FIGURES
1.1 Block diagram of multi-purpose alarm system
3.1 Flowchart on design and construction procedures
4.1 Internal circuit of 555 timer IC
4.2 Astable multivibrator circuit using inverters
4.3 Output waveform of 555 timer oscillator
4.4 Astable circuit configuration, using Rb = Rs + Rp
4.5 One short configuration using 555 timer IC unit
4.6 Waveform of triggered mode
4.7 One shot multivibrator circuit
4.8 Pin configuration of 74LS191
4.11 Functional block diagram for 74LS153
4.14 Circuit diagram of frequency multiplexer 74LS153
a) Basic common-emitter circuit
b) Load-line construction.
4.21 Transistor amplifier arrangement with signal symbol
4.22 Transistor amplifier arrangement with signal symbol
4.23 Amplifier configuration component values
4.31 Pin configuration of 74LS175
4.32 Functional block diagram of Quadruple D-type FF (74LS175)
4.41 Typical IC encoder
4.42 8 line-to-line priority encoder 74LS148
4.44 Bimetallic heat detector
4.45 Time temperature curve
5.1 Isometric diagram of package multi-purpose alarm system.
LIST OF TABLES
4.01 Table of various frequencies of operation from the oscillator unit
4.11 Table of result of frequency derision
4.12 Table for the 74LS153 multiplexer operation
4.31 Functional table for D-type flip flop 74LS175
4.41 Functional table of 74LS148 priority encoder.
LIST OF ABBREVIATIONS AND SYMBOLS
IC Integrated Circuit
Vcc +5 Volt Supply
GND Ground or Earth
FF Flip Flop
TTL Transistor-transistor logic
CMOS Complementary Metallic Oxide Semi Conductor Logic
C/M Count Up
C/O Count Down
EL Enabled Input
EO Enabled Output
VCE Collector Emitter Voltage
VBE Base-Emitter Voltage
VCB Collector Base Voltage
IB Base Current
RB Base Current
L/S Loud Speaker
Kâ„¦ Kilo ohms
Dip Dual in line package
TABLE OF CONTENTS
List of tables
List of abbreviations
Table of contents
Objective of the project
Detection and switching unit
Human shadow detector
Human touch sensor
The hatch circuit
The alarm circuit
The display board
Power supply unit
Obtaining project topic and specifications
Choosing a suitable circuit
Selecting component values
Construction and testing
Operation of a transistor
Switching operation of a transistor
Test, demonstration and packaging
Tools and materials
Conclusion and Recommendations