Project ReportON

MOBILE PHONE DETECTORSubmitted In Partial Fulfillment of the Requirements for the

Diploma of Electronics and Telecommunication EngineeringBy

Mr. Pankaj Rai

Under the guidance of Ms.Meenal Vatsaraj

DEPARTMENT OF ELECTRONICS AND TELECOMMUNICATION ENGINEERING (DIPLOMA)

ARMIET

Alamuri Ratnamala Institute of Engineering and Technology

(Run by Koti Vidya Charitable Trust)

A.S. Rao Nagar, Sapgaon, Tal Shahapur, Dist Thane-421601

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Alamuri Ratnamala Institute of Engineering and Technology

(Run by Koti Vidya Charitable Trust)

A.S. Rao Nagar, Sapgaon, Tal Shahapur, Dist Thane-421601

Project Report Submitted ByName: Mr. Pankaj Rai

Title of project: MOBILE PHONE DETECTOR

Guide Name: Ms. Meenal Vatsaraj

Ms. Meenal Vatsaraj Mr. Nagababu Chekuri Mr. Nagababu Chekuri (Project Guide) (H.O.D.) (Principal)

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CERTIFICATEThis is to certify that Mr.Pankaj Rai has delivered a project

report for the Project Topic “MOBILE PHONE DETECTOR” and submitted report in the “Alamuri Ratnamala Institute of Engineering and Technology”, Sapgaon, Tal Shahapur, Dist, Thane, in the partial fulfillment of the diploma of “Electronics

and telecommunication Engineering” from MSBTE for the year 2015-16

Guide H.O.D. Principal

Ms. Meenal Vatsaraj Nagababu Chekuri Nagababu Chekuri

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AcknowledgementI would like to acknowledge and extend our heartfelt gratitude to all those people who have been

associated with this project and have helped us with it thus making it a worthwhile experience.

Firstly I extend our thanks to various people which include my project Guide Ms. Meenal

Vatsaraj my H.O.D. Nagababu Chekuri, who have shared their opinions and experiences through

which I received the required information for my report. I am also thankful to all the staff

members of EXTC Dept. for their highly cooperative and encouraging attitudes, which have

always boosted me.

I also take this opportunity with great pleasure to thank our Honorable Founder Trustee A.V.

Gupta, Honorable Alternate Chairman Dr. L.S. Bothra and Principal Prof. Nagababu Chekuri

whose timely support and encouragement has helped us succeeds in our venture.

Pankaj Rai

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INDEX

Sr. Topic Name Page No.

1 Abstract 9

2 List of acronyms 10

3 Introduction 11

1 Background 11

2 History 12

3 Cellular Phone Technology 13

4 Cellular Phone Communication Standard 14

5 Secure Facilities 15

6 Overview 16

7 Problem statement 17

8 Motivation 18

4 Mobile Phone Detector 19

5 Different Types of Design 20

6 Basic Information about Detector 21

7 Block Diagram 22

8 Block Diagram Explanation 23

9 Circuit Diagram 24

10 Circuit Explanation 25

11 Component Used 26

12 Capacitor 27

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13 Ceramic capacitor 28

14 Electrolytic capacitor 29

15 Resistor 30

16 Transistor 31

17 LED 32

18 Piezo Buzzer 33

19 Component Specification 34

20 IC Diagram IC555 35

21 Pin Description of IC555 36

22 IC Diagram of IC3130 37

23 Pin Description of IC3130 38

24 Advantages of Mobile Phone Detector 39

25 Application 40

26 Conclusion 41

27 Future scope 42

28 Reference 43

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Table Description

Sr. No. Table Name Page No.

1 Component Specifications 34

2 Pin Description of IC NE555 36

3 Pin Description of IC CA3130 38

7

Diagram Description

Sr. No. Diagram Name Page. No

1 Berkeley Varitronics Systems Wolfhound Cellphone Detector 20

2 Cellbusters Cell Phone Detector 20

3 Block Diagram 22

4 Circuit Diagram 24

5 IC NE555 35

6 Pin Diagram 35

7 IC CA3130 37

8 Pin Diagram 37

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AbstractThis work involves the design and development of a digital signal detector which is capable of

detecting incoming and outgoing signals from mobile phones. The presence of an activated

mobile phone can be detected by this handy, pocket-size mobile signal detector from a distance

of one and a half meters, which could be used in preventing the use of mobile phones in

examination halls, confidential rooms etc. It is also suitable for detecting the use of mobile phone

for spying and unauthorized video transmission. The circuit can detect the incoming and outing

calls, text messages, and video transmission even if the mobile is kept in the silent mode. The

moment the gadget detects Radio Frequency (RF) transmission signal from an activated mobile

phone, it starts sounding a beep alarm and the Light Emitting Diode (LED) blinks. The alarm

continues until the signal transmission ceases. The circuit is assembled on a general purpose

PCB as compact as possible and enclosed in a small box.

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List of Acronyms

GSM Global system for mobile

RF Radio Frequency

AM Amplitude Modulation

FM Frequency Modulation

LED Light Emitted Diode

BJT Bipolar Junction Transistor

UJT Unipolar Junction Transistor

FET Field Effect Transistor

JFET Junction Field Effect Transistor

MOSFET Metal Oxide Semiconductor Field Effect Transistor

CMOS Complementary Metal Oxide Semiconductor

TTL Transistor-Transistor Logic

OP-AMP Operational Amplifier

UHF Ultra High Frequency

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Introduction

1. Background

In recent years, there has been increasing focus on issues relating to the use of mobile

phones in restricted, prohibited, and unauthorized areas. The reason for this increased interest is

largely due to disturbance, as well as wrong and inappropriate usage of mobile phones by the

owners and users alike. Other areas like churches, mosques, offices, and prisons, just to mention

a few, are not left out. There is need for the detection of mobile phone signals in areas like these.

Efforts have been put in place in tackling this issue but they all have their own

shortcomings, one of which is the mobile phone jammer. A mobile phone jammer is an

instrument used to prevent cellular phones from receiving signals from base stations. When used,

the jammer effectively disables cellular phones. These devices can be used in practically any

location, but are found primarily in places where a phone call would be particularly disruptive

because silence is expected.

Mobile phones uses RF with a wavelength of 30cm at 872 to 2170 MHz that is, the signal

is high frequency with huge energy. When the mobile phone is active, it transmits the signal in

the form of sine wave which passes through the space. The encoded audio/video signal contains

electromagnetic radiation which is picked up by the receiver in the base station.

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2. History

Since cellular phone detection is a more recent problem, there are only a few articles that have

already researched this area. Two articles were published in 2007 and provide good analysis.

Thefirst article, "Detecting and Locating Cell Phones in Correctional Facilities," was written by

EVI Technology, LLC. The second article, "Cell Phone Detection Techniques," was written by a

Contractor hired by the U.S. Department of Energy (DOE).

This article details the growing problem with cellular phones in correctional facilities and lays

out the constraints used to develop their solution. According to the research, cellular phones in a

correctional facility are used to operate criminal enterprises, threaten witnesses, harass victims,

plan uprisings, and undermine security. Their problem is monitoring, controlling, and locating

cellular phones in a correctional facility. EVI's possible solutions include physical search, non-

linear junction detectors, signal jamming, shielding, network provider location based screening,

RF detection, and their custom proprietary solution. They rule out all solutions but their own

custom solution that uses a system of networked sensors that are controlled by a central

computer. EVI uses proprietary software that determines the cell phone's location and detects any

RF emissions. The location of detected cellular devices is displayed on a 14 facility map

This solution was developed for detecting cellular phones in a prison. It relies on the cellular

phone remaining stationary which, in prison facilities makes sense since movement is limited.

EVI's detection system finds cellular phones after they have already been in the facility for at

least 30 minutes or if someone is making a cell phone call. EVI doesn't provide any details on the

signal detection technique used since it is all proprietary. Also, there are no reviews or articles

stating that this system works as advertised

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3.Cellular Phone Technology

Cellular phonetechnology is rapidly changing. Features like Bluetooth, USB, high resolution

cameras, microphones, Internet, 802.11 wireless, and memory cards are added every year.Also,

the communication technology a cellular phone uses such as CDMA, GSM, 3G, and 4G are

rapidly changing.

Bluetooth is a secure wireless protocol that operates at 2.4 GHz. The protocol uses a master slave

structure and is very similar to having a wireless USB port on your cellular phone. Devices like a

printer, keyboard, mouse, audio device, and storage device can be connected wirelessly.This

feature is mainly used for hands-free devices but can also be used for file transfer of

pictures,music, and other data. Universal serial bus (USB) is a way for cellular phones to connect

to a computer for data transfer. This feature is very similar toBluetooth for a cellular phone with

the exception of using a cable. On today's cellular phones this feature is mainly used for charging

the battery or programming by the manufacturer. It can also be used to transfer pictures, music,

and other data. Cameras on cellular phones are a very popular feature that was added in the last

10 years. In recent years, high resolution camerashave become a standard feature. Most cellular

phones will come with at least a 2 mega pixel camera and the more expensive phones canbe as

much as 8 mega pixels. Microphones have been featured on cellular phones since they first came

out.In the last 10 years the microphones have become dual purpose;now there are programs on

the phone that record voice to file such as a simple voice recorder or as part of a video. Almost

every available cellular phone today has a connection to the Internet. This allows users to

transfer files and data wherever they are. Cellular phones can send emails, text messages, picture

text messages, videotext messages, and upload data to the Internet. Some cellular phones come

with 802.11 wireless built in and allows the phone to connect to any nearby wireless networks.

This provides an alternate connection method to the Internet and saves money if you're on a

limited data plan. Also, connecting with 802.11 is most likely going to provide better throughput

than using the cellular phone network.

Since cameras and music have become popular features on cellular phones, manufacturers have

started adding memory card slots. These memory cards provide expanded memory and allow

more pictures to be taken or music files to be stored. Most memory cards can plug directly into

the computer for easy data transfer. All these features make cellular phones today very versatile.

They can connect with almost any storage medium or computer. In the years to come, cellular

phones will continue to gain more and more features.

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4.Cellular Phone Communication Standards

Currently the three main technologies used by cellular phone providers are 2G,3G, and 4G.

Each generation of technology uses a different transmission protocol. Thetransmission

protocols dictate how a cellular phone communicates with the tower. Someexamples are:

frequency division multiple access (FDMA), time division multiple access(TDMA), code division

multiple access (CDMA), global system for mobilecommunications (GSM) , CDMA2000,

wideband code division multiple access(WCDMA), and time-division synchronous code-division

multiple access (TD-SCDMA).All of these protocols typically operate in the 824- 894 MHz band

in the United States.Some protocols, such as GSM (depending on the provider)will use the 1800

- 2000 MHzband

To provide a good example of how a cellular phone transmission works, take a look at Diagram

1 which shows how FDMA works. Each phone call uses a different frequency within the 45

MHz bandwidth. FDMA is normally used for analog transmissions and is capable of digital

transmissions

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5. Secure Facilities

Many businesses such as psychiatric hospitals, correctional facilities, pharmsutical

companies, government facilities, and military bases rely on keeping information protected.

They build security fortresses that shield their money making information from getting to the

general public. These have many computers that house the valuable information and are not

connected to the Internet. Generally, access is restricted by guards with metal detectors and

electronic devices are not allowed in or out without proper approval. 6 In every secure facility

it is hard to ensure that employees and visitors aren't violating the policies. The only way to

ensure someone isn't carrying a cellular phone is to search everyone as they enter and exit.

This requires a great deal of manpower and most companies can't afford that level of

security.Additionally, it will make the employees feel like the company doesn't trust them.

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6. Overview

As increase in the technology in the world using electronics equipment are being used in a

wrong way like, in the examination hall and confidential room.to avoid this we are introducing a

project called CELL PHONE DETECTOR

This handy, pocket-size mobile transmission detector or sniffer can sense the presence

of an activated mobile phone from a distance of one and half-meter.so it can be used to prevent

use of mobile phone in examination hall, confidential rooms, etc.it is also use full for detecting

the use of mobile phone for spying and unauthorized video transmission. The circuit can detect

the incoming and outgoing calls, SMS and video transmission even if the mobile phone is kept in

the silent mode. the movement dug detects RF transmission signal from an activated mobile

phone.it starts sounding a beep alarm and the LED blinks .the alarm continue until the signal

transmission ceases

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7. Problem Statement

Previously, there was no technology to detect the cell phones in the examination hall and in cell

phone restricted areas. There is manual checking and there is still a change of having the cell

phone with the person if he is not checked properly. So to avoid this problem, an automatic

detection of cell phone is introduced

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8. Motivation

Cell phones are used in good way and also in a bad way. when the class is going on,

students intend to use there cell phones and not listening to what is being taught. These days,

students are also carrying their cell phones to the examination halls to copy which would help

them to get good marks

To avoid this problem, the cell phone detector is introduced

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Mobile Phone Detector

We are most familiar with cell phone active detectors. The cell phone detectors are mostly hand

and pocket-size mobile transmission detectors. It can sense the presence of an activated mobile

phone from a distance of one and a half meters. So it can be used to prevent use of mobile

phones in examination halls, confidential rooms, etc.

It is also useful for detecting the use of mobile phone for spying and un-authorized video

transmission. Certain places where use of mobile phones are not allowed like exam hall, temple,

offices and theaters, in those places to detect and restrict the use of mobile phones this proposed

system is very helpful. This must detect the incoming and outgoing calls, SMS and video

transmission even if the mobile phone is kept in the silent mode. The illegal use of cell phones is

a growing and dangerous problem in correctional institutions worldwide. These devices are a

significant threat to prison security and circumvent the monitoring processes in prisons, while

helping inmates commit new crimes both inside and outside the facility.

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20

Different Types Of Design

1. Berkeley Varitronics Systems Wolfhound Cellphone Detector

Berkeley Varitronics Systems Wolfhound Cellphone Detector

2. Cellbusters Cell Phone Detector

Cellbusters Cell Phone Detector

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Basic Information about Detector

The transmission frequency of mobile phones ranges from 0.9 to 3 GHz with a wavelength of 3.3

to 10 cm. So a circuit detecting gigahertz signals is required for a mobile bug. The lead length of

the capacitor is fixed as 18 mm with a spacing of 8 mm between the leads to get the desired

frequency. The disk capacitor along with the leads acts as a small gigahertz loop antenna to

collect the RF signals from the mobile phone.

When mobile phone is active, it transmits the signal in the form of sine wave which passes

through the space. The encoded audio/video signal contains electromagnetic radiation which is

picked up by the receiver in the base station. The transmitter power of the modern 2G antenna in

the base station is 20-100 watts. The mobile phone transmits short signals at regular intervals to

register its availability to the nearest base station. Distance to cellular base station is the most

important environmental factor. Generally, the nearer a cellular phone is to a base station or

transmitting tower, the weaker will be the signal that needs to come from the phone. Range of

frequencies of different categories are, AM radio frequencies between 180 kHz and 1.6MHz,FM

radio uses 88 to 180 MHz, TV uses 470 to 854MHz.waves at higher frequencies but within the

RF region is called Micro waves. Mobile phone uses high frequency RF wave in the micro wave

region carrying huge amount of electromagnetic energy.

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Antenna Frequency Comparator Timer

Indicator

BLOCK DIAGRAM

Block Diagram

23

Block Diagram of Cell Phone Detector:

The circuit uses a 0.22μF disk capacitor to capture the RF signals from the mobile phone. This

part should be like an aerial, so the capacitor is arranged as a mini loop aerial. In short with this

arrangement the capacitor works like an air core with ability to oscillate and discharge current.

The output of transistor is within 10 mV of either supply voltage terminal. The lead inductance

acts as a transmission line that intercepts the signals from the mobile phone. An ordinary RF

detector using tuned LC circuits is not suitable for detecting signals in the GHz frequency band

used in mobile phones that’s why circuit detecting gigahertz signals is required for a mobile bug.

Op-amp is used in the circuit is act as a comparator. It may come with MOSFET inputs and

bipolar output. The input contains MOSFET transistors to provide very high input impedance

very low input current. It has high speed of performance and suitable for low input current

application. Hence the result is in very low input current and very high speed of performance. It

is used in applications like ground referenced single supply amplifiers, fast sample hold

amplifiers, long duration timers etc.

IC-555 is a highly stable controller capable of producing accurate timing pulses. With the

monostable operation the time delay is controlled by one external resistor and one capacitor.

With an astable operation the frequency and duty cycle are accurately controlled by two external

resistors and one capacitor. These are used in applications like precision timing, pulse

generation, time delay generation etc.

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Circuit Diagram

Circuit Diagram

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CIRCUIT EXPLANATION

Here the circuit uses a 0.22μF disk capacitor (C3) to capture the RF signals from the

mobile phone. The lead lengthof the capacitor is fixed as 18 mm with a spacing of 8 mm

between the leads to get the desired frequency. The disk capacitoralong with the leads acts as a

small gigahertz loop antenna to collect the RF signals from the mobile phone.

Op-amp IC CA3130 (IC1) is used in the circuit as a current-to-voltage converter with

capacitor C3 connected betweenits inverting and non-inverting inputs. It is a CMOS version

using gate-protected p-channel MOSFET transistors in the inputto provide very high input

impedance, very low input current and very high speed of performance.The output CMOS

transistor is capable of swinging the output voltage to within 10 mV of either supply voltage

terminal.

Capacitor C3 in conjunction with the lead inductance acts as a transmission line that

intercepts the signals from themobile phone. This capacitor creates a field, stores energy and

transfers the stored energy in the form of minute current tothe inputs of IC1.This will upset the

balanced input of IC1 and convert the current into the corresponding output voltage.

Capacitor C4 along with high-value resistor R1 keeps the non-inverting input stable for

easy swing of the output tohigh state. Resistor R2 provides the discharge path for capacitor C4.

Feedback resistor R3 makes the inverting input highwhen the output becomes high.

Capacitor C5 (47pF) is connected across ‘strobe’ (pin 8) and ‘null’ inputs (pin 1) of IC1 forphase

compensation and gain control to optimize the frequency response.

When the mobile phone signal is detected by C3, the output of IC1 becomes high and low

alternately according to thefrequency of the signal as indicated by LED1. This triggers

Monostable timer IC2 through capacitor C7. Capacitor C6maintains the base bias of transistor T1

for fast switching action. The low-value timing components R6 and C9 producevery short time

delay to avoid audio nuisance.

Assemble the circuit on PCB and enclose in a small box like junk mobile case. As

mentioned earlier, capacitor C3should have a lead length of 18 mm with lead spacing of 8

mm.carefully solder the capacitor in standing position with equalspacing of the leads. Use the

miniature 12V battery of a remote control and a small buzzer to make the gadgetpocket-size.

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COMPONENTS USED

Operational Amplifier (CA3130)

Timer (NE555)

Capacitors

Resistors

Buzzer

LED

Transistors

Antenna

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CAPACITOR

A capacitor or condenser is a passive electronic component consisting of a pair of

conductors separated by a dielectric. When a voltage potential difference exist between the

conductors, an electric field is present in the dielectric. This field stores energy and products a

mechanical force between the plate. The effect is greatest between wide, flat, parallel, narrowly

separated conductors

An ideal capacitor is characterized by a single constant valve, capacitance, which is

measured in farads. This is the ratio of the electric charge on each conductors to the potential

difference between them. In practice, the dielectric between the plates passes a small amount of

leakage current. The conductors and leads introduce an equipment series resistance and the

dielectric has an electric field strength limit resulting in a breakdown voltage

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CERAMIC CAPACITOR

A ceramic capacitor is a fixed value capacitor in which ceramic material acts as the dielectric. It

is constructed of two or more alternating layers of ceramic and a metal layer acting as the

electrodes. The composition of the ceramic material defines the electrical behavior and therefore

applications. Ceramic capacitors are divided into two application classes:

Class 1 ceramic capacitors offer high stability and low losses for resonant circuit

applications.

Class 2 ceramic capacitors offer high volumetric efficiency for buffer, by-pass, and

coupling applications.

Ceramic capacitors, especially the multilayer style (MLCC), are the most produced and used

capacitors in electronic equipment that incorporate approximately one trillion (1012) pieces per

year

Class 1 ceramic capacitors are accurate, temperature-compensating capacitors. They offer the

most stable voltage, temperature, and to some extent, frequency. They have the lowest losses and

therefore are especially suited for resonant circuit applications where stability is essential or

where a precisely defined temperature coefficient is required, for example in compensating

temperature effects for a circuit. The basic materials of class 1 ceramic capacitors are composed

of a mixture of finely ground granules of paraelectric materials such as Titanium dioxide (TiO

2), modified by additives of Zinc, Zirconium, Niobium, Magnesium, Tantalum, Cobalt and

Strontium, which are necessary to achieve the capacitor’s desired linear characteristics

Class 2 ceramic capacitors have a dielectric with a high permittivity and therefore a better

volumetric efficiency than class 1 capacitors, but lower accuracy and stability. The ceramic

dielectric is characterized by a nonlinear change of capacitance over the temperature range. The

capacitance value also depends on the applied voltage. They are suitable for bypass, coupling

and decoupling applications or for frequency discriminating circuits where low losses and high

stability of capacitance are less important.

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ELECTROLYTIC CAPACITOR

An electrolytic capacitor is a type of capacitor that uses an ionic conducting liquid as one of its

plates with a larger capacitance per unit volume then other types. They are valuable in relatively

high-current and low-frequency electric circuits. This is especially the case in power supply

filters. Where the store charge needed to moderate output voltage and current fluctuations in

rectifier output. They are also widely used as coupling capacitor in circuit where AC should be

conducted but DC should not

Electrolytic capacitors can have a very high capacitance. Allowing filters made with them to

have very low corner frequencies

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RESISTOR

A resistor is a passivetwo-terminalelectrical component that implements electrical resistance as

a circuit element. Resistors act to reduce current flow, and, at the same time, act to lower voltage

levels within circuits. In electronic circuits, resistors are used to limit current flow, to adjust

signal levels, bias active elements, and terminate transmission lines among other uses. High-

power resistors, that can dissipate many watts of electrical power as heat, may be used as part of

motor controls, in power distribution systems, or as test loads for generators. Fixed resistors have

resistances that only change slightly with temperature, time or operating voltage. Variable

resistors can be used to adjust circuit elements (such as a volume control or a lamp dimmer), or

as sensing devices for heat, light, humidity, force, or chemical activity.

Resistors are common elements of electrical networks and electronic circuits and are ubiquitous

in electronic equipment. Practical resistors as discrete components can be composed of various

compounds and forms. Resistors are also implemented within integrated circuits.

Ohm's law

The behavior of an ideal resistor is dictated by the relationship specified by Ohm's law:

Ohm's law states that the voltage (V) across a resistor is proportional to the current (I), where the

constant of proportionality is the resistance (R). For example, if a 300 ohm resistor is attached

across the terminals of a 12 volt battery, then a current of 12 / 300 = 0.04 amperes flows through

that resistor.

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TRANSISTOR

A transistor is a semiconductor device commonly used to amplify or switch electronic signal. .A

transistor is made of a solid piece of a semiconductor material. with at least there terminals for

connection to an external circuit. A voltage or current applied to one pair of the transistors

terminals changes the current flowing through another pair of terminals. Because the controlled

(output) power can much more than the controlling (input) power, the transistor provides

amplification of a signal. Some transistors are packaged individually but most are found in

integrated circuit

The transistor is fundamental building block of modern electronic devices, and its

presence is ubiquitous in modern electronic system

Advantages

The key advantagesthat have allowed transistors to replace their vaccum tube predecessors in

most applications are

Highly automated manufacturing process, resulting in low per-unit cost.

No warm-up period for cathode heater required after power application.

Small size and minimal weight, allowing the development of miniaturized electronic

devices.

Lower possible operating voltage, making transistors suitable for small, battery-

powered applications

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Light-emitting Diode (LED)

A light-emitting diode (LED) is an electronics light source. LEDs are used as

indicator lamps in many kinds of electronics for lighting. LEDs work by the effect of

elctroluminescence, discovered by accident in 1907. LED was introduced as a practical

electronic component in 1962. All early devices emitted low-intensity red light, but modern

LEDs are available across the visible, ultraviolet and infrared wavelength, with very high

brightness.

LEDs present many advantages over traditional light source including low energy

consumption, longer lifetime, improved robustness, smaller size and switching. However. They

are relatively expensive and require more precise current and heat management than traditional

light source

Applications of LEDs are diverse. they are used as low-energy indicators but also for

replacement for traditional light source in general lighting,automotive lighting and traffic signal.

The compact size of LEDs has allowed new text and video display and sensors to be developed,

while their high switching rates are useful in communication technology.

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PIEZO BUZZER

Piezoelectricity is the ability of some materials (notably crystals and certain

ceramics, including bone) to generate an electric field or electric potential in response to applied

mechanical stress.the effect is closly related to a change of polarization density within the

materials valum. If material is not short-circuited,the applied stress induces a voltage across the

material. The world is derived from the Greek piezo or piezein, which means to squeeze or press

A buzzer or beeper is a signaling device. usually electronic, typically used in

automobiles, household appliances such as microwave ovens, or game shows.

It most commonly consists of a number of switches or sensors connected to a control

unit that determines if and which buttons was pushed or a preset time has lapsed, and usually

illuminates a light on the appropriate button or control panel, and sounds a warning in the form

of a continues or intermittent buzzing or beeping sound

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Component Specifications

Component Name Component Value

Resistor

R1 = 2.2 Ω

R2 = 100K Ω

R3 = 2.2 Ω

R4 = 1K Ω

R5 = 12K Ω

R6 = 15K Ω

Capacitor

C1 = 22pF

C2 = 22pF

C3 = 0.22 µF

C4 = 100µF

C5 = 47pF

C6 = 0.1µF

C7 = 0.1µF

C8 = 0.01µF

C9 = 4.7µF

Power Supply 12V

Component Specifications

35

Component Diagram

IC NE555

NE555

______________________________________________________________

Pin Diagram

Pin Diagram

36

Pin Description of IC NE555

Pin Number Pin Name Description

1 -Offset +OFFSET NULL

2 -Input INVERTING INPUT

3 +Input NON-INVERTING INPUT

4 V- NEGETIVE POWER SUPPLY

5 +Offset -OFFSET NULL

6 O/p OUTPUT

7 V+ POSITIVE POWER SUPPLY

8 NC DUMMY PIN

Pin Description of IC NE555

__________________________________________________________________

37

IC CA3130

IC CA3130

Pin Diagram

Pin Diagram

38

Pin Description of IC CA3130

Pin Number Pin Name Description

1 GND Ground

2 TRIG Start Timing Input

3 OUT High Current Timer Output

and Discharge timing

capacitor

4 RESET Reset Pin

5 CONT Control Pin

6 THRES Threshold Pin

7 DISCH Discharge Pin

8 VCC Input Supply Voltage

Pin Description of IC CA3130

39

Advantages of Cell Phone Detector:

Smaller in size

Detection of hidden cell phones

Low Cost

More Reliable

Simple Circuit

Less Component Used

Can be Install Anywhere

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APPLICATIONS

It can be used to avoid the usage of mobile phones in examination hall, seminar hall,

quizzes etc.

It can be used to avoid video transmission in secret or private meeting.

It can be used for military and civil defense purpose to detect mobile phone body

increasing is radius of range.

It can be used in hospitals and airplanes where, mobile signals interfere with the

electronic equipment which may have fatal consequences.

Petrol pumps

Gas station

Historical places

Religious places

Court of laws

Examination halls

Spying and unauthorized video transmission

Military bases

Hospitals

Theatres

Conferences

Embassy

FUTURE SCOPE

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Trying to increase the detecting range of cell phone detector to few more meter for

observing wide range of area

42

CONCLUSION

It is the technology which will make every student mad

No one can break the rule

References

43

By Books

Linear Integrated circuits :RamakantGaikwad

Electronic Devices and Circuits :Salivahan

Electronic Devices and Circuits :Millman and Halkias

Electronic Devices and Circuits :Boylestad

By Websites

http://www.circuitbasics.com/build-a-great-sounding-audio-amplifier-with-bass-boost-from-the-

lm386/

http://www.learningaboutelectronics.com/Articles/How-to-connect-a-LM386-audio-amplifier-

chip

http://www.electroschematics.com/552/lm386-audio-amplifier/

http://www.ti.com/lit/ds/symlink/lm386.pdf

http://www.electronicsforu.com/electronicsforu/circuitarchives/view_article.asp?

sno=74&article_type=1&id=466&tt=unhot

http://8085projects.info/principles-and-application-of-the-op-amp-lm324.html

http://www.engineersgarage.com/electronic-components/lm324n-datasheet

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