Electronic Watch Dog Project
Traditionally and even now many people have pet dogs
stationed at their entrance. The purpose of the dogs is that
they bark whenever a person enters through the door. This is
what names this project as Electronic Watch Dog Project as it
performs the same task of detecting the presence of a person
at the entrance of a premises.
A pair of IR sensor transmitter and receiver are placed at the
entrance of the premises that needs to be secured. This is
what does the trick in our case in this project. When a person
or an intruder who doesn’t knows about the security device
installed at the entrance enters through the door, the IR rays
gets cut. This cutting of IR rays triggers a series of events in
the circuit eventually ringing a burglar alarm. Hearing the alarm
the owner of the premises can come to know that someone
has entered through the door.
Similarly, this device can be installed whichever perimeter is
needed to be secure from intruders.
The IR rays from transmitter reaches the IR receiver making it
signal to the 555 IC know that currently there is no present in
between the sensors. But as soon as an intruder cuts the IR
rays, the receiver output changes resulting the 555 IC to
trigger. This eventually leads in triggering UM66 IC. Due to
these series of events the speaker connected at the output of
the circuit board starts ringing thus notifying about the
intruder at the secured permeter.
Block Diagram
Project Development Stages
Circuit Design
PCB Printing
Components Procurement
Soldering
Testing for Connectivity & Issues
Circuit Design
A circuit is actually any loop through
which matter is carried. For an
electronic circuit, the matter carried
is the charge by electronics and the
source of these electrons is the
positive terminal of the voltage
source .When this charge flows from
the positive terminal, through out
the loop and reaches the negative
terminal, the circuit is said to be
completed. However this circuit
consists of a number of components
which affects the flow of charge in
many ways. Some may provide
hindrance to the flow of charge,
some simple store or dissipate
charge. Some require external
source of energy, some supply
energy.
Circuit Design Tools:
•Eagle, Kicad, Proteus
•Circuit Digest Capacitor Calculator
•NevonExpress Resistor Color Code Calculator
Components Procurement
Component Procurement is a time consuming and difficult task.
Components required for project research and development are not
easily available in market and local shops.
Soldering
With silver soldering, small pieces
of solder wire are placed onto the
metal prior to heating. A flux,
often made of boric acid and
denatured alcohol, is used to keep
the metal and solder clean and to
prevent the solder from moving
before it melts.
Testing for Connectivity & Issues
Testing Tools:
•Multimeter
•Power Supply
•Oscilloscope
PCB Printing
A printed circuit board
mechanically supports and
electrically connects electronic
components or electrical
components using conductive
tracks, pads and other features
etched from one or more sheet
layers of copper laminated onto
and/or between sheet layers of a
non-conductive substrate.
HARDWARE REQUIREMENTS
▪ IR tx/rx
▪ 555 timer
▪ Speaker
▪ Transitor
▪ Resistors
▪ Capacitors
▪ Push Button
▪ Crystal Oscillator
▪ Cables & Connectors
▪ Diodes
▪ PCB
▪ LED’s
▪ Transformer/Adapter
Infrared IR Sensor
It is made up of both 5mm 940 nanometer wave span high
power IR LED and photodiode with peak sensitivity in 940
nanometer wavelength. An infrared sensor is a digital device,
that releases so as to feel some facets of the environment.
An IR sensor may gauge the warmth of an item in addition to
finds the motion.These kinds of sensors measures just infrared
radiation, instead of emitting it that's referred to a passive IR
sensor.
555 Timer IC
• IC 555 timer is one of the most frequently used IC in electronic
equipment and can be utilized in various digital circuits because of its
robust and secure attributes. The 555 timer obtained its name in the 3
5k ohm resistor connected in a voltage-divider design.
• The 555 timer IC is also an essential portion of electronic equipment
jobs. Can it be a very simple endeavor involving just one 8 bit
micro-controller plus a few peripherals or a complicated one involving
program on chips (SoCs), 555 timer functioning is included. Time
delays are provided by these, as an oscillator and as a element among
programs.
Features
• Timing from Microseconds through Hours
• Operates in Both Astable and Monostable Modes
• Adjustable Duty Cycle
• Output Can Source or Sink 200 mA
• Output and Supply TTL Compatible
• Temperature Stability Better than 0.005% per ºC
• Short-circuit protected output
• Available in 8-pin VSSOP Package
BC547 Transistor
BC547 is a NPN transistor hence the collector and emitter is going to be left
available (Reverse suggestive) whenever the foundation pin is held at ground
and will be shut (Forward biased) when a sign is provided to base pin. BC547 has
a profit value of 110 to 800, this value determines the capacity of the transistor.
The maximum amount of current that may flow through the Collector snare is
100mA, therefore we cannot connect. To bias a transistor we must provide
current to base pin, this current (IB) should be limited to 5mA.
Features
Bi-Polar NPN Transistor
DC Current Gain (hFE) is 800 maximum
Continuous Collector current (IC) is 100mA
Emitter Base Voltage (VBE) is 6V
Base Current(IB) is 5mA maximum
Available in To-92 Package
Buzzer
A buzzer or beeper is an audio signaling device, which may be mechanical,
electromechanical, or piezoelectric. Typical uses of buzzers and beepers include
alarm devices, timers and confirmation of user input such as a mouse click or
keystroke.
This one is petite but loudly! Drive it with 3-30V peak-to-peak square wave. To
use, join one pin to ground (either one) and another pin into a square wave from
a timer or microcontroller. For the tones, remain around 4 KHz, however, works
well from 2KHz to 10KHz. For additional loudness, you can connect both pins
into a microcontroller and swap that pin is high or low ('differential drive') for
double the volume.
Resistors
The resistor is a passive electrical component to create resistance in the flow
of electric current. In almost all electrical networks and electronic circuits they
can be found. The resistance is measured in ohms. An ohm is the resistance
that occurs when a current of one ampere passes through a resistor with a
one volt drop across its terminals. The current is proportional to the voltage
across the terminal ends. This ratio is represented by Ohm’s law:
formula with ohm's law: R=V/I
Resistors are used for many purposes. A few examples include delimit
electric current, voltage division, heat generation, matching and loading
circuits, control gain, and fix time constants. They are commercially available
with resistance values over a range of more than nine orders of magnitude.
They can be used to as electric brakes to dissipate kinetic energy from trains,
or be smaller than a square millimeter for electronics.
Resistors Code Calculation
Resistor Calculations requires color code
charts for resistor value calculations.
Capacitors
The capacitor is a component which has the ability or “capacity” to store energy in the form of an
electrical charge producing a potential difference (Static Voltage) across its plates, much like a small
rechargeable battery.
There are many different kinds of capacitors available from very small capacitor beads used in
resonance circuits to large power factor correction capacitors, but they all do the same thing, they
store charge.
In its basic form, a capacitor consists of two or more parallel conductive (metal) plates which are not
connected or touching each other, but are electrically separated either by air or by some form of a
good insulating material such as waxed paper, mica, ceramic, plastic or some form of a liquid gel as
used in electrolytic capacitors. The insulating layer between a capacitors plates is commonly called
the Dielectric.
Due to this insulating layer, DC current can not flow through the capacitor as it blocks it allowing
instead a voltage to be present across the plates in the form of an electrical charge.
The conductive metal plates of a capacitor can be either square, circular or rectangular, or they can
be of a cylindrical or spherical shape with the general shape, size and construction of a parallel plate
capacitor depending on its application and voltage rating.
Diodes
A diode is a two-terminal electronic component that conducts current primarily in one
direction (asymmetric conductance); it has low (ideally zero) resistance in one direction,
and high (ideally infinite) resistance in the other. A diode vacuum tube or thermionic
diode is a vacuum tube with two electrodes, a heated cathode and a plate, in which
electrons can flow in only one direction, from cathode to plate. A semiconductor diode,
the most common type today, is a crystalline piece of semiconductor material with a p–n
junction connected to two electrical terminals.[5] Semiconductor diodes were the first
semiconductor electronic devices. The discovery of asymmetric electrical conduction
across the contact between a crystalline mineral and a metal was made by German
physicist Ferdinand Braun in 1874. Today, most diodes are made of silicon, but other
materials such as gallium arsenide and germanium are used.
The most common function of a diode is to allow an electric current to pass in one
direction (called the diode's forward direction), while blocking it in the opposite direction
(the reverse direction). As such, the diode can be viewed as an electronic version of a
check valve.
Buttons & Switches
A push-button (also spelled pushbutton) or simply button is a simple switch mechanism
for controlling some aspect of a machine or a process. Buttons are typically made out of
hard material, usually plastic or metal.[1] The surface is usually flat or shaped to
accommodate the human finger or hand, so as to be easily depressed or pushed.
Buttons are most often biased switches, although many un-biased buttons (due to their
physical nature) still require a spring to return to their un-pushed state. Terms for the
"pushing" of a button include pressing, depressing, mashing, slapping, hitting, and
punching.
PCB – Printed Circuit Board
A printed circuit board (PCB) mechanically supports and electrically connects electronic
components or electrical components using conductive tracks, pads and other features
etched from one or more sheet layers of copper laminated onto and/or between sheet
layers of a non-conductive substrate. Components are generally soldered onto the PCB
to both electrically connect and mechanically fasten them to it.
Printed circuit boards are used in all but the simplest electronic products. They are also
used in some electrical products, such as passive switch boxes.
Alternatives to PCBs include wire wrap and point-to-point construction, both once
popular but now rarely used. PCBs require additional design effort to lay out the circuit,
but manufacturing and assembly can be automated. Specialized CAD software is
available to do much of the work of layout. Mass-producing circuits with PCBs is cheaper
and faster than with other wiring methods, as components are mounted and wired in one
operation. Large numbers of PCBs can be fabricated at the same time, and the layout
only has to be done once. PCBs can also be made manually in small quantities, with
reduced benefits.
Transformer & Adapters
A transformer is a static electrical device that transfers electrical energy
between two or more circuits. A varying current in one coil of the
transformer produces a varying magnetic flux, which, in turn, induces a
varying electromotive force or "voltage" across a second coil wound around
the same core.
An AC adapter, AC/DC adapter, or AC/DC converter is a type of external
power supply, often enclosed in a case similar to an AC plug. Other
common names include plug pack, plug-in adapter, adapter block,
domestic mains adapter, line power adapter, wall wart, power brick, and
power adapter.
Tools Needed
Multimeter is needed for testing of electronics pcb based projects for voltage,
connectivity and other issues.
Soldering iron is used along with soldering accessories to ensure proper
connectivity between components and the pcb surface and ensure proper
working of the system.
Bibliograpgy / Reference Links
Transistor-https://nevonexpress.com/Buy-Transistors-Online.php
555 timerIC-https://nevonexpress.com/search.php?stext=555%20Timer%20IC
Resistors - https://nevonexpress.com/Buy-Resistors-Online.php
Capacitors - https://nevonexpress.com/Buy-Capacitors-Online.php
Diodes - https://nevonexpress.com/Buy-Diodes-Online.php
Push Button - https://nevonexpress.com/Buy-Electronics-Buttons-Switches-Online.php
Crystal Oscillator - https://nevonexpress.com/Buy-Crystal-Oscillator-Online.php
Cables & Connectors - https://nevonexpress.com/Cables-&-Connectors.php
PCB - https://nevonexpress.com/Buy-PCB-Breadboards-Online.php
Transformer/Adapter - https://nevonexpress.com/Transformers.php
THA N K YOU
