“INTELLIGENT JAMMER”

MINI PROJECT REPORT

Submitted in partial fulfillment of the requirements

for the award of the Degree of Bachelor of Technology in

Electronics and Communication Engineering of the University of Kerala.

Done By,

KIRAN SANKER (REG NO: 11419010)

PREJITH PAVANAN (REG NO: 11419013)

TONY GEORGE (REG NO:11419021)

VISHNU B S (REG NO:11419022)

DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING

P.A AZIZ COLLEGE OF ENGINEERING AND TECHNOLOGY

KARAKULAM, THIRUVANANTHAPURAM

2014

DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING

P.A AZIZ COLLEGE OF ENGINEERING AND TECHNOLOGY

KARAKULAM, THIRUVANANTHAPURAM

2014

CERTIFICATE

This is to certify that the mini project entitled “INTELLIGENT JAMMER” is a

bonafide record of project presented by PREJITH PAVANAN (REG NO:11419013)

under our guidence towards fulfillment of the requirements for the award of the Degree

of Bachelor of Technology in Electronics and Communication Engineering of the

University of Kerala in the year 2014.

Project Guide Head of Department Project Guide

Mrs.ASWATHY.A Mr.JAGANATHAN.L.C Mrs.SINI JOSEPH

Asst.professor Professor Asst.professor

Dept.of AEI Dept. of ECE Dept.of AEI

PAACET PAACET PAACET

INTERNAL EXAMINER EXTERNAL EXAMINER

i

ACKNOWLEDGEMENT

Before we get to the thick of things, we present our wholehearted

complements, with higher regards and warm thanks to one and all, who were

the bone behind the sinews of this project.

We give all glory and honour to Almighty God whose blessings and help

made this endeavour a success.

We express our sincere gratitude to Mr.E.MOHAMMED THAHA,

Chairman P.A.AZIZ College of Engineering and Technology for providing us

the required facilities. We wish to express our sincere thanks to our Principal,

Mr.VIJAYAN BABURAJ for providing an opportunity to under take this

project. We hereby acknowledge our sincere thanks to Prof.JAGANATH.L.C,

our H.O.D for his invaluable remarks and supervision in completing this project

work successfully.

Also we would like to express our boundless thanks and gratitude to

Mrs.ASWATHY.A, Asst.professor and Mrs.SINI JOSEPH, Asst.professor in

AEI Dept for their valuable guidance and suggestions in the whole course of

our mini project activity.

It would be unfair if we do not mention the contribution and timely co-

operation extended by staff members of our dept.

We would like to thank our Institution without which this project would

have been a distant reality. We also extend our gratitude to our family and well

wishers.

Not the least, but the most ,we are grateful to all the 6th semester students

of this institution, our beloved companions for the inspiration and the co-

operation they have shown at all levels of our work.

ii

ABSTRACT

The ubiquity of the cell phone has made communication easier and faster,

integrating the world into a global village as people who are in different

geographic location are connected in seconds, it's great to be able to call anyone

at any time. There is great need to limit the use of cell phone at particular places

and at particular times. Hence, the use of intelligent cell phone detector is

guaranteed. This work concentrates in designing a system that will dictate the

presence of GSM signals from an unauthorized user in restricted areas which

will in turn trigger another device to restrict the user from service. The system

will be able to jam GSM frequency signal upon detection to prevent the

transmitted signal from getting to the users cell phone.

iii

TABLE OF CONTENTS

CHAPTER NO TITLE PAGE NO:

ACKNOWLEDGEMENT i

ABSTRACT ii

LIST OF FIGURES v

1. INTRODUCTION 1

1.1. CELL PHONE DETECTOR 2

1.2. CELL PHONE JAMMER 2

2. BLOCK DIAGRAM 4

3. BLOCK DIAGRAM DESCRIPTION 5

3.1. DETECTOR CIRCUIT 5

3.1.1. RF ANTENNA 5

3.1.2. CE AMPLIFIER 6

3.1.3. TIMER CIRCUIT 6

3.1.4. LED 7

3.2. JAMMER CIRCUIT 8

3.2.1. BATTERY 9

3.2.2. OSCILLATOR 9

3.2.3. TUNING CIRCUIT 11

3.2.4. NOISE GENERATOR 13

3.2.5. AMPLIFIER 14

3.2.6. ANTENNA 15

4. CIRUIT DIAGRAM 17

5. CIRCUIT DIAGRAM DISCRIPTION 18

5.1. DETECTOR DESCRIPTION 18

5.2. JAMMER DESCRIPTION 18

6. COMPONENT DESCRIPTION 20

iv

6.1. NE 556 20

6.2. TRASNSISTOR 22

6.2.1. BC 548 23

6.2.2. 2SC3355 TRASISTOR 24

6.2.3. BFR96 24

6.3. RESISTOR 25

6.4. CAPACITOR 26

6.5. DIODES 27

7. LAYOUT 28

7.1. PCB LAYOUT 28

7.2. COMPONENT LAYOUT 30

8. PCB FABRICATION 32

9. SOLDERING 34

9.1. SOLDER 34

9.2. FLUX 35

9.3. SOLDERING IRON 35

9.4. SOLDERING STEPS 36

10. APPLICATIONS 37

11. ADVANTAGES 38

12. DISADVANTAGES 39

13. CONCLUSION 40

14. BIBILIOGRAPHY 41

15. DATASHEETS 42

v

LIST OF FIGURES

CHAPTER TITLE PAGE NO:

2.1. CELL PHONE JAMMER & 4

DETECTOR

2.2. CELL PHONE DETECTOR 4

2.3. CELL PHONE JAMMER 4

4.1. CIRCUIT DIAGRAM OF 17

CELL PHONE DETECTOR

4.2. CIRCUIT DIAGRAM OF 17

CELL PHONE JAMMER

6.1.1. NE555 20

6.2.0. TRANSISTOR 22

6.2.1.1. BC 548 23

6.2.2.1. 2SC3355 24

6.2.3.1. BFR96TS 24

6.3.1. RESISTORS 25

6.4.1. CAPACITORS 26

6.5.1. DIODE 27

7.1.1. PCB LAYOUT OF 28

CELL PHONE DETECTOR

7.1.2. PCB LAYOUT OF 29

CELL PHONE JAMMER

7.2.1. COMPONENT LAYOUT OF 30

CELL PHONE DETECTOR

7.2.2. COMPONENT LAYOUT OF 31

CELL PHONE JAMMER

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CHAPTER 1

INTRODUCTION

The rapid proliferation of cell phones at the beginning of the 21st century

to near ubiquitous status eventually raised problems such as their potential use

to invade privacy or contribute academic cheating. In addition public backlash

was growing against the intrusive disruption cell phones introduced in daily life.

While older analog cell phones often suffered from chronically poor reception

and could even be disconnected by simple interference such as high frequency

noise, increasingly sophisticated digital phones have led to more elaborate

counters. Intelligent Cell phone devices are alternative to more expensive

measures against denial of services by service providers. This work

concentrates in designing a system that will dictate the presence of GSM signals

from an unauthorized user in restricted areas which will in turn trigger another

device to restrict the user from service. The system will be able to jam GSM

frequency signal upon detection to prevent the transmitted signal from getting to

the users cell phone The Intelligent Cell phone detection project is an advanced

device which finds various applications in the modern fields of communication

and surveillances. This work is very useful for the private meetings,

examination hall, defence establishments, military camp, Hospitals; Petrol

pumps etc., where the uses of an active Cell phone Communication (GSM)

device are prohibited.

This objective is achieved by splitting the working of the device into two

parts-

1) Cell phone detection

2) Cell phone jamming

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1.1. Cell phone detector

As we told earlier there are two parts for this project it is a detection part

and a jammer part, the first part a.k.a detector is said to be an intelligent switch

of the jammer. The detector detects the radio wave emerging out from the cell

phone of about 800-900MHz range and it activates the circuit. The Cell phone

detection project is an advanced device which finds various applications in the

modern fields of communication and surveillances. Cell phone detection project

is designed to detect the cell phone in a closed room / place which is in active

transmission mode. This project is very useful for the private meetings, defence

establishments, military camp, Hospitals; Petrol pumps etc., where the uses of

an active Cell phone Communication (GSM) device are prohibited. With the aid

of this project, one can detect the active cell phone device like Cell Phone and

GPS systems. Here the Cell phone detection project can be used like a metal

detector and the project is capable of detecting the Cell phone like device from

the range of few centimetres to few inches depending upon the Cell phone

transmission strength and other parameters. Here the project is waved near the

person / place where the presence of a GSM device is to be detected.

1.2. Cell phone jammer

Cell phones work by communicating with a service network through the

utilization of cellular towers or base stations. Individual towers partition cities

into small sections called cells. As a cell phone user traverses the cells in an

area, the signal is passed from tower to tower.

Jamming devices take advantage of this fact by transmitting on the

spectrum of radio frequencies used by cellular devices. Through its concurrent

transmission, the jamming device is able to disrupt the two-way communication

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between the phone and the base station. This form of a denial-of-service attack

inhibits all cellular communication within range of the device.

Through the transmission of a high power signal on the same frequency

of a cell phone, the jamming device creates a competing signal that collides

with, and, in effect, cancels out the cellular signal. Cell phones, which are

designed to increase power in the case of low levels of interference, react to this

interference. Consequently, jamming devices must be aware of any increases in

power by the cellular device and match that power level accordingly.

As cellular telephones are full-duplex devices utilizing two separate

frequencies (one for talking, one for listening, where all parties to a call can talk

at the same time as opposed to half-duplex walkie-talkies and CBs), any

removal of one of these frequencies tricks the phone into thinking there is no

cellular service. Consequently, the jammer need only block one of the

frequencies.

The less complex jammers can only block a specific frequency group

while the more complex jammers can block several different networks thus

preventing dual- or tri-mode phones from switching to a different network with

an open signal. Jammers are able to broadcast on any frequency and can

interrupt, GSM, UMTS etc. The effective range of a jammer is dependent upon

the strength of its power source and the immediate physical environment (hills

or walls which may block the jamming signal). Lower powered jammers have a

call-block range of about 2 feet while higher power units can create a cellular

signal-free zone about the size of a football field. In addition, certain units

applied by law enforcement have been known to shut down cellular service

approximately 1 mile from the jamming device.

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CHAPTER 2

BLOCK DIAGRAM

2.1. Cell phone detector and jammer circuit.

2.2. Block diagram of Detector circuit

2.3. Block diagram of jammer circuit

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CHAPTER 3

BLOCK DIAGRAM DESCRIPTION

The main purpose of the overall system is to disable or block cell phone

phones in the restricted area. As shown in Figure 1 the system is designed to

work as a Cell phone detector. It detects the RF signals from cell phone phones

and relay a signal to the trigger of the jamming circuit and this in turn blocks the

desired frequency (GSM 900, GSM1800)

3.1. Detector circuit

`The description is as follows.

1. RF antenna

2. CE amplifier

3. Timer circuit

4. LED

3.1.1. RF antenna

An antenna (or aerial) is an electrical device which converts power

into radio waves, and vice versa. It is usually used with a radio transmitter or

radio. In transmission, a radio transmitter supplies an electric current oscillating

at radio frequency (i.e. high frequency AC) to the antenna's terminals, and the

antenna radiates the energy from the current as electromagnetic waves (radio

waves). In reception, an antenna intercepts some of the power of an

electromagnetic wave in order to produce a tiny voltage at its terminals, that is

applied to a receiver to be amplified.

Antennas are essential components of all equipment that uses radio. They

are used in systems such as radio broadcasting, broadcast television, two-way

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radio, communications receivers, radar, cell phones, and satellite

communications, as well as other devices such as openers,

wireless, Bluetooth enabled devices, wireless computer networks etc.

3.1.2. CE amplifier

An antenna (or aerial) is an electrical device which converts power

into radio waves, and vice versa. It is usually used with a radio transmitter or

radio. In transmission, a radio transmitter supplies an electric current oscillating

at radio frequency (i.e. high frequency AC) to the antenna's terminals, and the

antenna radiates the energy from the current as electromagnetic (radio waves).

In reception, an antenna intercepts some of the power of an electromagnetic

wave in order to produce a tiny voltage at its terminals, that is applied to a

receiver to be amplified.

Antennas are essential components of all equipment that uses radio. They

are used in systems such as radio broadcasting, broadcast television, two-way

radio, communications receivers, radar, cell phones, and satellite

communications, as well as other devices such as openers,

wireless, Bluetooth enabled devices, wireless computer networks etc.

3.1.3. Timer circuit

The 556 timer IC is an integrated circuit (chip) used in a variety of timer,

pulse generation, and oscillator applications. The 556 can be used to provide

time delays, as an oscillator, and as a flip-flop element. Derivatives provide up

to four timing circuits in one package.

Depending on the manufacturer, the standard 556 package includes

25 transistors, 2 diodes and 15 resistors on a silicon chip installed in an 8-pin

mini dual-in-line package (DIP-8). Variants available include the 556 (a 14-pin

DIP combining two 556s on one chip), and the two 558 & 559s (both a 16-pin

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DIP combining four slightly modified 556s with DIS & THR connected

internally, and TR is falling edge sensitive instead of level sensitive).

The NE556 parts were commercial temperature range, 0 °C to +70 °C,

and the SE556 part number designated the military temperature range, −55 °C

to +125 °C. These were available in both high-reliability metal can (T package)

and inexpensive epoxy plastic (V package) packages. Thus the full part numbers

were NE556V, NE556T, SE556V, and SE556T. It has been hypothesized that

the 556 got its name from the three 5 kΩ resistors used within, but Hans

Camenzind has stated that the number was arbitrary

Low-power versions of the 556 are also available, such as the 7556 and

CMOS TLC556. The 7556 is designed to cause less supply noise than the

classic 556 and the manufacturer claims that it usually does not require a

"control" capacitor and in many cases does not require a decoupling

capacitor on the power supply. Those parts should generally be included,

however, because noise produced by the timer or variation in power supply

voltage might interfere with other parts of a circuit or influence its threshold

voltages.

3.1.4. LED

A light-emitting diode (LED) is a two-lead semiconductor light source

that resembles a basic pn-junction diode, except that an LED also emits light.

When an LED's anode lead has a voltage that is more positive than its cathode

lead by at least the LED's forward voltage drop, current flows. Electrons are

able to recombine with holes within the device, releasing energy in the form of

photons. This effect is called electroluminescence, and the colour of the light

(corresponding to the energy of the photon) is determined by the energy band

gap of the semiconductor.

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An LED is often small in area (less than 1 mm2), and integrated optical

components may be used to shape its radiation pattern.

Appearing as practical electronic components in 1962, the earliest LEDs

emitted low-intensity infrared light. Infrared LEDs are still frequently used as

transmitting elements in remote-control circuits, such as those in remote

controls for a wide variety of consumer electronics. The first visible-light LEDs

were also of low intensity, and limited to red. Modern LEDs are available

across the visible, ultraviolet, and infrared wavelengths, with very high

brightness.

Early LEDs were often used as indicator lamps for electronic devices,

replacing small incandescent bulbs. They were soon packaged into numeric

readouts in the form of seven-segment displays, and were commonly seen in

digital clocks.

3.2. Jammer circuit

The description is as follows.

1. Battery

2. Oscillator

3. Tuning circuit

4. Noise generator

5. Amplifier

6. Antenna

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3.2.1. Battery

The most common form of nine-volt battery is commonly called

the transistor battery, introduced for the early transistor radios. This is a

rectangular prism shape with rounded edges and a polarized snap connector at

the top. This type is commonly used in pocket radios, smoke detectors, carbon

monoxide detectors, guitar effect units, electro-acoustic guitars and radio-

controlled vehicle controllers. They are also used as backup power to keep the

time in certain electronic clocks. This format is commonly available in primary

carbon-zinc and alkaline chemistry, in primary lithium iron disulfide, and in

rechargeable form in nickel-cadmium, nickel-metal hydride and lithium-ion.

Mercury oxide batteries in this form have not been manufactured in many years

due to their mercury content

Most nine-volt alkaline batteries are constructed of six individual 1.5V

LR61 cells enclosed in a wrapper.[2]

These cells are slightly smaller than

LR8D425 AAAA cells and can be used in their place for some devices, even

though they are 3.5 mm shorter. Carbon-zinc types are made with six flat cells

in a stack, enclosed in a moisture-resistant wrapper to prevent drying

3.2.2. Oscillator

An electronic oscillator is an electronic circuit that produces a repetitive,

oscillating electronic signal, often a sine wave or a square wave. Oscillators

convert direct current (DC) from a power supply to an alternating current signal.

They are widely used in many electronic devices. Common examples of signals

generated by oscillators include signals broadcast by radio and television

transmitters, clock signals that regulate computers and quartz clocks, and the

sounds produced by electronic beepers and video games.

Oscillators are often characterized by the frequency of their output signal:

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An audio oscillator produces frequencies in the audio range, about 16 Hz to

20 kHz.

An RF oscillator produces signals in the radio frequency (RF) range of about

100 kHz to 100 GHz.

A low-frequency oscillator (LFO) is an electronic oscillator that generates a

frequency below ≈20 Hz. This term is typically used in the field of

audio synthesizers, to distinguish it from an audio frequency oscillator.

Oscillators designed to produce a high-power AC output from a DC

supply are usually called inverters.

In an RC oscillator circuit, the filter is a network

of resistors and capacitors. RC oscillators are mostly used to generate lower

frequencies, for example in the audio range. Common types of RC oscillator

circuits are the phase shift oscillator and the Wien bridge oscillator.

In an LC oscillator circuit, the filter is a tuned circuit (often called a tank

circuit; the tuned circuit is a resonator) consisting of an inductor (L)

and capacitor (C) connected together. Charge flows back and forth between

the capacitor's plates through the inductor, so the tuned circuit can store

electrical energy oscillating at its resonant frequency. There are small losses

in the tank circuit, but the amplifier compensates for those losses and

supplies the power for the output signal. LC oscillators are often used

at radio frequencies, when a tuneable frequency source is necessary, such as

in signal, tuneable radio transmitters and the local oscillators in radio

receivers. Typical LC oscillator circuits are

the Hartley, Colpitts and Clapp circuits.

In a crystal oscillator circuit the filter is a piezoelectric crystal (commonly

a quartz crystal). The crystal mechanically vibrates as a resonator, and its

frequency of vibration determines the oscillation frequency. Crystals have

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very high Q-factor and also better temperature stability than tuned circuits,

so crystal oscillators have much better frequency stability than LC or RC

oscillators. Crystal oscillators are the most common type of linear oscillator,

used to stabilize the frequency of most radio transmitters, and to generate

the clock signal in computers and quartz clocks. Crystal oscillators often use

the same circuits as LC oscillators, with the crystal replacing the tuned

circuit; the Pierce oscillator circuit is also commonly used. Quartz crystals

are generally limited to frequencies of 30 MHz or below. Surface acoustic

wave (SAW) devices are another kind of piezoelectric resonator used in

crystal oscillators, which can achieve much higher frequencies. They are

used in specialized applications which require a high frequency reference,

for example, in cellular telephones.

3.2.3. Tuning circuit

In electronics an LC circuit, also called a resonant circuit, tank circuit,

or tuned circuit, consists of two electronic components connected together;

an inductor, represented by the letter L, and a capacitor, represented by the letter

C. The circuit can act as an electrical resonator, an electrical analogue of

a tuning fork, storing energy oscillating at the circuit's resonant frequency.

LC circuits are used either for generating signals at a particular

frequency, or picking out a signal at a particular frequency from a more

complex signal. They are key components in many electronic devices,

particularly radio equipment, used in circuits such

as oscillators, filters, tuners and frequency mixers.

An LC circuit is an idealized model since it assumes there is no

dissipation of energy due to resistance. Any practical implementation of an LC

circuit will always include loss resulting from small but non-zero resistance

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within the components and connecting wires. The purpose of an LC circuit is

usually to oscillate with minimal damping, so the resistance is made as low as

possible. While no practical circuit is without losses, it is nonetheless instructive

to study this ideal form of the circuit to gain understanding and physical

intuition

An LC circuit can store electrical energy oscillating at its resonant

frequency. See the animation at right. A capacitor stores energy in the electric

field (E) between its plates, depending on the voltage across it, and an inductor

stores energy in its magnetic (B), depending on the current through it.

If a charged capacitor is connected across an inductor, charge will start to

flow through the inductor, building up a magnetic field around it and reducing

the voltage on the capacitor. Eventually all the charge on the capacitor will be

gone and the voltage across it will reach zero. However, the current will

continue, because inductors resist changes in current. The energy to keep it

flowing is extracted from the magnetic field, which will begin to decline. The

current will begin to charge the capacitor with a voltage of opposite polarity to

its original charge. When the magnetic field is completely dissipated the current

will stop and the charge will again be stored in the capacitor, with the opposite

polarity as before. Then the cycle will begin again, with the current flowing in

the opposite direction through the inductor.

The charge flows back and forth between the plates of the capacitor,

through the inductor. The energy oscillates back and forth between the capacitor

and the inductor until (if not replenished by power from an external circuit)

internal resistance makes the oscillations die out. Its action, known

mathematically as a harmonic oscillator, is similar to a pendulum swinging back

and forth, or water sloshing back and forth in a tank. For this reason the circuit

is also called a tank circuit. The oscillation frequency is determined by the

capacitance and inductance values. In typical tuned circuits in electronic

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equipment the oscillations are very fast, thousands to millions of times per

second.

3.2.4. Noise generator

In electronics, noise is a random fluctuation in an electrical signal, a

characteristic of all electronic circuits. Noise generated by electronic devices

varies greatly, as it can be produced by several different effects. Thermal

noise is unavoidable at non-zero temperature (see fluctuation-dissipation

theorem), while other types depend mostly on device type (such as shot

noise, which needs steep potential barrier) or manufacturing quality

and semiconductor defects, such as conductance fluctuations, including 1/f

noise.

In communication systems, noise is an error or undesired random

disturbance of a useful information signal in a communication channel. The

noise is a summation of unwanted or disturbing energy from natural and

sometimes man-made sources. Noise is, however, typically distinguished

from interference, (e.g. cross-talk, deliberate jamming or other

unwanted electromagnetic interference from specific transmitters), for example

in the signal-to-noise ratio (SNR), signal-to-interference ratio (SIR) and signal-

to-noise plus interference ratio (SNIR) measures. Noise is also typically

distinguished from distortion, which is an unwanted systematic alteration of the

signal waveform by the communication equipment, for example in the signal-

to-noise and distortion ratio (SINAD). In a carrier-modulated pass band analog

communication system, a certain carrier-to-noise ratio (CNR) at the radio

receiver input would result in a certain signal in the detected message signal. In

a digital communications system, a certain Eb/N0 (normalized signal-to-noise

ratio) would result in a certain bit error rate (BER)

A Noise generator is a circuit that produces electrical noise (i.e., a

random signal). Noise generators are used to test signals for measuring noise

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figure, frequency response, and other parameters. Noise generators are also used

for generating random numbers.

3.2.5. Amplifier

Low-noise amplifier (LNA) is an electronic amplifier used to amplify

possibly very weak signals (for example, captured by an antenna). It is usually

located very close to the detection device to reduce losses in the feed line.

This active antenna arrangement is frequently used in microwave systems

like GPS, because coaxial cable feed line is very lossy at microwave

frequencies, e.g. a loss of 10% coming from few meters of cable would cause a

10% degradation of the signal-to-noise ratio (SNR).

An LNA is a key component which is placed at the front-end of a radio

receiver circuit. Per Friis' formula, the overall noise figure (NF) of the

receiver's front-end is dominated by the first few stages (or even the first stage

only).

Using an LNA, the effect of noise from subsequent stages of the receive

chain is reduced by the gain of the LNA, while the noise of the LNA itself is

injected directly into the received signal. Thus, it is necessary for an LNA to

boost the desired signal power while adding as little noise and distortion as

possible, so that the retrieval of this signal is possible in the later stages in the

system. A good LNA has a low NF (e.g. 1 dB), a large enough gain (e.g. 20 dB)

and should have large enough intermodulation and compression point (IP3 and

P1dB). Further criteria are operating bandwidth, gain flatness, stability and

input and output voltage standing wave ratio (VSWR).

For low noise, the amplifier needs to have a high amplification in its first

stage. Therefore JFETs and HEMTs are often used. They are driven in a high-

current regime, which is not energy-efficient, but reduces the relative amount

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of shot noise. Input and output matching circuits for narrow-band circuits

enhance the gain

3.2.6. Antenna

An antenna (or aerial) is an electrical device which converts power

into radio waves, and vice versa. It is usually used with a radio transmitter or

radio. In transmission, a radio transmitter supplies an electric current oscillating

at radio frequency (i.e. high frequency AC) to the antenna's terminals, and the

antenna radiates the energy from the current as electromagnetic (radio waves).

In reception, an antenna intercepts some of the power of an electromagnetic

wave in order to produce a tiny voltage at its terminals, that is applied to a

receiver to be amplified.

Antennas are essential components of all equipment that uses radio. They

are used in systems such as radio broadcasting, broadcast television, two-way

radio, communications receivers, radar, cell phones, and satellite

communications, as well as other devices such as openers,

wireless, Bluetooth enabled devices, networks, baby, and RFID tags on

merchandise.

Typically an antenna consists of an arrangement of metallic conductors

(elements), electrically connected (often through a transmission line) to the

receiver or transmitter. An oscillating current of electrons forced through the

antenna by a transmitter will create an oscillating magnetic field around the

antenna elements, while the charge of the electrons also creates an

oscillating electric field along the elements. These time-varying fields radiate

away from the antenna into space as a moving transverse electromagnetic field

wave. Conversely, during reception, the oscillating electric and magnetic fields

of an incoming radio wave exert force on the electrons in the antenna elements,

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causing them to move back and forth, creating oscillating currents in the

antenna.

Antennas may also include reflective or directive elements or surfaces not

connected to the transmitter or receiver, such as parasitic, parabolic

reflectors or horns, which serve to direct the radio waves into a beam or other

desired radiation pattern. Antennas can be designed to transmit or receive radio

waves in all directions equally (Omni directional antennas), or transmit them in

a beam in a particular direction, and receive from that one direction only

(directional or high gain antennas).

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CHAPTER 4

CIRCUIT DIAGRAM

4.1. Cell phone detector

4.2. Cell phone jammer circuit diagram

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CHAPTER 5

CIRCUIT DIAGRAM DESCRIPTION

5.1. Detector Description

Consider when a call is coming to our cell phone as when the call comes

there will be a radiation around the phone this radiation is just a typical

electromagnetic interference this interference or the EM wave triggers the

inductor in the circuit creating a potential at the base of the transistor

As when there is a voltage at the base of the transistor there will be a

potential produced at the collector terminal of the transistor BC548 this output

will triggers the pin 2 of the NE-556 IC as when the trigger is applied to the IC

there will be a pulse output at the pin3 of the transistor .

Here the supply voltage of the circuit is 1.5v when the interference is

caused at the base of the transistor it triggers the ic and the output obtained will

be a small voltage it adds up with the 1.5v supply and the led to glow and hence

the switch is made.

5.2. Jammer Description

This signal jammer uses 800MHz frequency to operate because many cell

phones are working on the same frequency. So choose the sweeping oscillator

asVCO.

The clock oscillator (45MHz) is driving a local oscillator port as my noise

source and is located on the mixer of the mini circuit. To equate the impedance

of a clock oscillator with the mixer there is an impedance matching network.

Local oscillator signal goes through this network and impedance is matched.

The 800MHz antenna from the old cell phone is connected to the RF

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input (mixer port). The RF output then goes to the amplifier located on the mini

circuit. The amplifier will increase produced output by 15-16dbm of pure

power. The empowered signal is going to another old phone antenna.

The timer ic in the circuit provides an oscillation by a connecting to an

oscillator more specifically a LC oscillator whose output is fed to the noise

generator part. The noise generator part is the main part of a cell phone jammer

because it mixes with the signal creating debris which turns down the entire

signal on the surrounding. The output from the noise generator is then fed to an

amplifier to amplify the noise created in the circuit which is then fed to an

antenna connected to the collector terminal of the amplifier hence the signal of

the phones lying next to the apparatus is shut down

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CHAPTER 6

COMPONENT DESCRIPTION

6.1.NE 555

6.1.1. NE 555

The 555 timer integrated circuit (IC) has become a mainstay in

electronics design. A 555 timer will produce a pulse when a trigger signal is

applied to it. The pulse length is determined by charging then discharging a

capacitor connected to a 555 timer. A 555 timer can be used to debounce

switches, modulate signals, create accurate clock signals, create pulse width

modulated (PWM) signals, etc. A 555 timer can be obtained from various

manufacturers including Fairchild Semiconductor and National Semiconductor.

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Pins of the 555 timer are as follows:

Gnd Ground connection for chip

Trigger 555 timer triggers when this pin transitions from voltage at Vcc

to 33% v voltage a Vcc. Output pin goes high when triggered

Output pin of 555 timer

Reset Resets 555 timer when low

Vcc 5V to 15 V supply input

Discharge Used to discharge a capacitor

Threshold Used to detect when the capacitor has charged. The Output pin

goes low w when capacitor has charged to 66.6% of Vcc.

Control Voltage Used to change Threshold and Trigger set point voltages

and is rarely used

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6.2. TRANSISTOR

6.2.0. Transistor symbol

A transistor is a semiconductor device used

to amplify and switch electronic signals and electrical power. It is composed

of semiconductor material with at least three terminals for connection to an

external circuit. A voltage or current applied to one pair of the transistor's

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

controlled (output) power can be higher than the controlling (input) power, a

transistor can amplify a signal. Today, some transistors are packaged

individually, but many more are found embedded in integrated circuits.

The transistor is the fundamental building block of modern electronic

devices, and is ubiquitous in modern electronic systems. The transistor

revolutionized the field of electronics, and paved the way for smaller and

cheaper radios, calculators, and computers, among other things.

In any switching circuit, values of input voltage would be chosen such

that the output is either completely off or completely on. The transistor is acting

as a switch, and this type of operation is common in digital circuits where only

"on" and "off" values are relevant.

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6.2.1. BC 548

6.2.1.1. BC 548

The BC548 is a general purpose epitaxial silicon NPN transistor found

commonly in European electronic equipment, and part of an historically

significant series of transistors that began in 1966 with Philips' introduction of

theBC108 and its high-voltage BC107 and low-noise BC109 variants. The

BC107/8/9 devices became the most used transistors in Australia and Europe,

and subsequent members of the series in plastic packages (such as

the BC547, BC548and BC549) retained the specifications of the metal-cased

BC107/8/9 essentially unchanged except for improvements - in thermal

resistance and reliability for example.

The part number is assigned by Pro Electron, which allows many

manufacturers to offer electrically and physically interchangeable parts under

one identification. The BC548 is commonly available in European Union

countries.

The pin out for the TO-92 package used for the BC546 to BC560 has pin

1 attached to the collector, pin 2 connected to the base, and pin 3 connected to

the emitter. Note that not all transistors with TO-92 cases follow this pin out

arrangement.

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6.2.2. 2SC3355

6.2.2.1. 2SC3355

The 2SC3355 is an NPN silicon epitaxial transistor designed for low

noise amplifier at VHF, UHF and CATV band. It has large dynamic range and

good current characteristic.

Features

Collector-Emitter Volt (Vceo): 12V

Collector-Base Volt (Vcbo): 20V

Collector Current (Ic): 0.1A

hfe: 50-300 @ 20Ma

6.2.3. BFR96TS

6.2.3.1. BFR96TS

The BFR96 transistor uses the same state–of–the–art microwave

transistor chip which features fine–line geometry, ion–implanted arsenic

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emitters and gold top metallization. This transistor is intended for low–to–medium power amplifiers requiring high gain, low noise figure, and low

intermodulation distortion. TheBFR96 is particularly suitable for broadband

MATV/CATV amplifiers.

6.3. RESISTORS

6.3.1. RESISTORS

A resistor is a passive two-terminal electrical component that implements

electrical as a circuit element. Resistors act to reduce current flow, and, at the

same time, act to lower voltage levels within circuits.

The current through a resistor is in direct proportion to the voltage across

the resistor's terminals. This relationship is represented by Ohm's law:

where I is the current through the conductor in units of amperes, V is the

potential difference measured across the conductor in units of volts, and R is the

resistance of the conductor in units of ohms (symbol: Ω).

Resistors are common elements of electrical networks and electronic

circuits and are ubiquitous in electronic equipment. Practical resistors can be

composed of various compounds and films, as well as resistance wires (wire

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made of a high-resistivity alloy, such as nickel-chrome). Resistors are also

implemented within integrated circuits, particularly analog devices, and can also

be integrated into hybrid and printed circuits.

6.4. CAPACITOR

6.4.1. CAPACITORS

A capacitor (originally known as a condenser) is a passive two-

terminal electrical component used to store energy electrostatically in an

electric. The forms of practical capacitors vary widely, but all contain at least

two electrical conductors (plates) separated by a dielectric (i.e., insulator). The

conductors can be thin films of metal, aluminium foil or disks, etc. The 'non

conducting' dielectric acts to increase the capacitor's charge capacity. A

dielectric can be glass, ceramic, plastic film, air, paper, mica, etc. Capacitors are

widely used as parts of electrical circuits in many common electrical devices.

Unlike a resistor, a capacitor does not dissipate energy. Instead, a capacitor

stores energy in the form of an electrostatic field between its plates.

A capacitor consists of two conductors separated by a non-conductive

region. The non-conductive region is called the dielectric. In simpler terms, the

dielectric is just an electrical insulatorThe conductors thus hold equal and

opposite charges on their facing surfaces,[11]

and the dielectric develops an

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electric field. In SI units, a capacitance of one farad means that one coulomb of

charge on each conductor causes a voltage of one volt across the device

6.5. DIODES

6.5.1. DIODES

In electronics, a diode is a two-terminal electronic component with

asymmetric conductance; it has low (ideally zero) resistance to current in one

direction, and high (ideally infinite) resistance in the other. A semiconductor

diode, the most common type today, is a crystalline piece

of semiconductor material with a junction connected to two electrical

terminals. A vacuum tube diode has two electrodes, a plate (anode) and a heated

cathode. Semiconductor diodes were the first semiconductor. The first

semiconductor diodes, called cat's whisker diodes, developed around 1906, were

made of mineral crystals such as galena. Today, most diodes are made

of silicon, but other semiconductors such as selenium or germanium are

sometimes used

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CHAPTER 7

LAYOUT

7.1. PCB LAYOUT

7.1.1. Lay out of cell phone detector

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7.1.2. Lay out of cell phone jammer

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7.2. COMPONENT LAYOUT

7.2.1. Lay out of cell phone detector

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7.2.2. Lay out of cell phone jammer

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CHAPTER 8

PCB FABRICATION

Printed circuit board (PCB) is piece of art. The performance of an

electronic circuit depends on the layout and the design of PCB. A PCB

mechanically supports and connects components by conductive pathways,

etched from copper sheets laminated onto insulated substrate.PCB ape used to

rotate electrical current and signals through copper tracts which are firmly

bonded to base.

PCB fabrication involves the following steps:

1. Drawing the layout of the PCB in paper. The track layout of the

electronic circuit should be made in such a manner that the

paths are in easy routes. It is then transferred to a Mylar sheet. The

sheet is then touched with black ink.

2. The solder side of the Mylar sheet is placed on the shiny side of the

five-star-sheet and is placed in a frame. Then it is exposed to

sunlight with Mylar sheet facing the sunlight.

3. The exposed five-star sheet is put in hydrogen peroxide solution.

Then it is put in hot water and shook still unexposed region will

transparent.

4. This is put in cold water and then the rough side is stuck on to the

silk screen. This is then pressed and dried well.

5. The plastic sheet of five-star sheet is removed leaving the pattern

on the screen.

6. A copper clad sheet is cut to the size and cleaned. This is placed

under screen.

7. As it resistant ink if spread on the screen so that a pattern of tracks

and a pad is obtained on a copper clad sheet. It is then dried.

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8. The dried sheet is etched using Ferric chloride solution (32 Baume)

till all the unwanted copper is etched away. Swish the board to

keep each fluid moving. Lift up the PCB and check weather all

unwanted copper is removed. Etching is done by immersing the

marked copper clad in Ferric chloride solution after that the etched

sheet is dried.

9. The unwanted resist ink is removed using sodium hydroxide

solution holes are the dried.

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CHAPTER -9

SOLDERING

Soldering is the process of joining metals by using lower melting point to

weld or alloy with joining surface.

9.1. SOLDER

Solder is the joining material that melts below 420 degree connections

between components. The popularly used solders are alloys of tin (Sn) and lead

(Pb) that melting point of tin.

Types

1. Rosin core: - 60/40 Sn/Pb solder are the most commonly used for

electronics assembly. These are available in various diameter and are

most appropriate for small electron

2. Lead free:-lead free solder are used as more environmental-friendly

substitutes for leaded solder, but they are not as easy to use mainly

because of their higher melting point and poorer wetting properties.

3. Silver:-Silver solder are typically used for low resistance connections but

they have a higher melting point and are expensive than Sn/Pb solder.

4. Acid-core:-Acid-core solder should not be used for electronics. They are

intended for plumping or non-electronics assembly work. The acid-core

flux will cause corrosion of circuitry and can damage components.

5. Other special solder:-

Various melting point eutectics: These special solders are typically

used for non-electronics assembly of difficult to construct

mechanical items that must be assembled in a particular sequence.

Paste solders: These solders are used in the field application or in

specialised manufacturing application.

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9.2. FLUX

Flux is a chemical cleaning agent, flowing agent, or purifying agent.

Fluxes may have more than one function at a time. They are used in both

extractive metallurgy and metal joining. These agents served various functions,

the simplest being a reducing agent which prevented oxides from forming on

the surface of the molten metal, while others absorbed impurities into the slag

which could be scraped off the molten metal. As cleaning agents, fluxes

facilitate soldering, brazing, and welding by removing oxidation from the

metals to be joined.

In high-temperature metal joining processes (welding, brazing and

soldering), the primary purpose of flux is to prevent oxidation of the base and

filler materials. Tin-lead solder (e.g.) attaches very well to copper, but poorly to

the various oxides of copper, which form quickly at soldering temperatures.

Flux is a substance which is nearly inert at room temperature, but which

becomes strongly reducing at elevated temperatures, preventing the formation

of metal oxides.

The most commonly used in hand soldering of electronic compounds is

rosin, a combination of mild organic acid extracted from pine tree.

9.3. SOLDERING IRON

A soldering iron is a hand tool used in soldering. it supplies heat to melt

the solder so that it can flow into the joint between two work pieces.

A soldering iron is composed of a heated metal tip and an insulated

handle. Heating is often achieved electrically, by passing an electric current

(supplied through an electrical cord or battery cables) through a

resistive heating element. Cordless irons can be heated by combustion of gas

stored in a small tank, often using a catalytic heater rather than a flame. Simple

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irons less commonly used than in the past were simply a large copper bit on a

handle, heated in a flame.

9.4. SOLDERING STEPS

1. Make the layout of the circuit in the circuit. Plug in the chord of the

soldering iron the mains to get heated.

2. Straighten and clean the component leads using a blade or a knife.

3. Mount the components on the PCB by bending the leads of the

component. Use nose pliers.

4. Apply flux on the joints and solder the joints. Soldering must be in

minimum time to avoid dry soldering and heating up of the

components.

5. Wash the residue using water and brush.

6. Solder joints should be inspected when completed to determine if

they have been properly made.

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CHAPTER -10

APPLICATIONS

1. Cellular signal blockers are eminent as the most excellent alternative to

more costly measures against mobile phone. In fact, they were developed

for only military and the law enforcement to cut off communications by

terrorists and criminals.

2. It is also used to halt the use of particular remotely detonated chemical

substances.

3. Can be used in Jail, Theatres, Mosques, Schools etc with prior permit and

jamming strictly limited to the firm perimeter with zero leakage

4. Other important use is that this devise can be used by bomb squad for

diffusing bombs. This is because most of the bombs now a day are

triggered by the use of cell phones.

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CHAPTER 11

ADVANTAGES

Cell phones offer great conveniences to people all over the world. It

arouses new challenge on the safety of secret work. Now a day, copying in

examination, wiretap, gas station outburst, and medical negligence are taking

place due to mobile phones. Probably, it is one of the major reasons behind the

emergence of jammers. Advantages of cell phone jammers are vast. Basically,

jammers function under specific frequency and connect to the main station

through electromagnetic wave. It transmits sound and data through intonation

and baud rate. The device creates an unrecognizable code hindrance to jam a

cellular phone. Most jamming devices can jam only one frequency.

Only advanced devices can block multiple frequencies. Now, it is being

used in prison, theatre, conference centre, library, church, gas station, school

campus, government hospitals, and military site. Under the security of the

device you do not have to worry about outburst and information safety. The new

models are highly portable in nature. Diverse types of jammers are readily

available in the market. Advantages of cell phone jammers are immense. The

portable devices are particularly designed for small, safe and private places like

mobile cars, discussion room and confidential office. Nevertheless, it can

successfully block cellular phone communication in the range of 50-80 sq

meters.

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CHAPTER 12

DISADVANTAGES

You are paying for the usage of a specific service. Use of jammers

might prevent you from using a service after paying for that. You cannot call

the emergency help-line numbers. A jammer might ensure a quiet and peaceful

ride in a train or a bus, but that cannot be done of a risk of greater magnitude

hanging on your head. Jamming of mobile phone networks can be dangerous for

your security.

The cell phone jammer will block all the signals within its working

range, there may be grave consequences in an emergency. And even it may be

utilized by the criminals to take advantage of others. As it is reported in the

newspaper, because of the blocking device equipped in the car, a girl who was

raped by a tax driver could not make an emergency call and led to her death. In

regard of safety and emergency, the cell phone jammers are prohibited to use in

most countries and the lawbreakers will be given severe penalty.

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CHAPTER 13

CONCLUSION

At last we can say every device is acts as good aspects as well as bad

aspects. In many place cell phone jammer is useful but at many place it is a

problem .for this we can take a example that if at any place cell phone jammer

is on than anybody wants to use than there creates some problems. But its

overall performance is very good and helpful in our life.

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CHAPTER 14

BIBILIOGRAPHY

Journals Referred

1. Innovation: Magazine of Research &Technology,2000

2. Printed circuit design Online (Magazine)

3. Design Magazine

4. Journal of Instrumentation(JNIST).

Website

1. http://HowStu_Work.com

2. http://wikipedia.org

3. http://electronics.howstu_works.com/cell-phone-jammer.htm

4. http://blog.jammer-store.com/2009/11/how-mobile-jammers-

work/

5. http://whatisacellphonejammer.com

6. http://whatisacellphonejammer.com

7. http://blog.jammer-store.com/2009/11/how-mobile-jammers-work

8. http://phantom.co.il

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DATASHEET