METAL DETECTOR IN THE ESTEEMED GUIDANCE OF:MISS P.VANITHA By- P.Sindhuri (07AT1A0412) B.T.Vishnu Vihar (07AT1A0423) M.Vani Divyatha (07AT1A0411) M.Tejeswar (07AT1A0446) IN THE ESTEEMED GUIDANCE OF:MISS P.VANITHA ASST.PROF OF ECE DEPARTMENT

CONTENTS ABSTRACT CIRCUIT WORKING METHODOLOGY INTRODUCTION PRACTICAL CIRCUIT OBJECTIVES OF PROJECT PROJECT &REAL-TIME APPLICATIONS WHAT IS METAL DETECTOR HISTORY ADVANTAGES&DISADVANTAGES CONCLUSION BASIC CIRCUIT MODEL REFERENCES COMPONENTS USED METAL DETECTOR MODULES MODULES IN BASIC CIRCUIT

ABSTRACT Nowadays, there are a lot of criminal incidents such as terrorist attacks in hotels & malls. This device helps in detecting metallic objects residing in body. The device is called metal detector. This project is developed to detect lost metals like iron, nails, keys and coins .The first step is to design the control circuit to detect different electrical pulse wave which has a different frequency. It is based on electromagnetic field produced by coil entwined at metal substance.

OBJECTIVES OF THE PROJECT To study how to develop a system of metal detector To design a device which can use to detect any changing frequency & pulses and output comes as alarm by speaker To detect metal substance by using a simple circuit To know and familiarize the electronic components in terms of function, operation and the characteristic.

WHAT IS METAL DETECTOR ? A metal detector is simple electronic circuit used to detect & locate metallic objects above and below the surfaces

HISTORY The German physicist Heinrich Wilhelm Dove invented the induction balance system, which was incorporated into metal detectors a hundred years later. The modern development of the metal detector began in the 1930s, Gerhard Fisher design a machine which would detect metal using a search coil resonating at a radio frequency, he was granted the first patent for a metal detector. The first industrial metal detectors were developed in the 1960s and were used extensively for mining and other industrial applications.

INTRODUCTION METAL DETECTOR STYLES Metal detectors come in several physical styles "beachcomber," hand-held, and mounted styles can all be effective for their intended use. Hand-held detectors are smaller and less obtrusive than beachcomber detectors. They are also usually "powerful and sensitive enough to detect all concealed metal weapons, including the smallest knives and guns".

BASIC CIRCUIT OF METAL DETECTOR

COMPONENTS USED Transistors -BC547 Diodes -IN4148 Resistors Capacitors LED-5mm red Inductor coil Buzzer -27mm C.Tone Battery -9v

METAL DETECTOR MODULES Metal detector comprises of three modules Sensing coil Buzzer sound Indicating circuit Regulator circuit Oscillating circuit Metallic object

CIRCUIT WORKING HEART OF THE CIRCUIT- COLPITTS OSCILLATOR Positive feedback Voltage divider  Frequency is determined by the inductor and the two capacitors One of the key features of this type of oscillator is its simplicity and robustness.

MODULES IN BASIC CIRCUIT Metal detector comprises of three modules a. Oscillating circuit b. Regulator circuit c. Indicating circuit

CIRCUIT WORKING (contd..) a. Oscillating circuit consists of 1.a first transistor; 2.a second transistor; 3.adjustable resistor coupled to the emitter of the first transistor; and 4.inductor coupled to the base of the second transistor to control the conductive state.

CIRCUIT WORKING (contd..) b. Regulating circuit consists of 1.Charging circuit 2.Discharging circuit 3.Regulating transistor

CIRCUIT WORKING (contd..) c. Indicating circuit consists of 1.Diode 2.LED 3.Buzzer

PRACTICAL CIRCUIT OF METAL DETECTOR

PROJECT APPLICATIONS Coin shooting Prospecting Relic hunting Treasure hunting Beach combing

REAL-TIME APPLICATIONS Airport security Building security  Event security  Item recovery  Archaeological exploration  Geological research 

ADVANTAGES In Schools: The metal detectors in schools are used to reduce any possible risk of violence by right and prompt signals such as beeps and alarms when the detectors find person carrying destructive weapons like knives, guns, bomb etc. IN INDUSTRIES: Industrial metal detectors are used in the pharmaceutical, food, beverage, textile, garment, plastics, chemicals, lumber, and packaging industries.

DISADVANTAGES False Reading Constitutional Rights Medical Interference

FUTURE SCOPE MODIFICATIONS IN METAL DETECTOR HELPS TO DISTINGUISH DIFFERENT METALS LIKE FERROUS AND NON FERROUS METALS (GOLD,SILVER ETC..,) AND ALSO HOW MUCH DISTANCE IS THAT METAL FROM COIL

CONCLUSION Generally, this project become as a role that can give a contribution for all people with one system which is effective and accomplished to handle stolen, robbery and used for finding something that were lost. This is because, this project was build using simple electronic circuit and not too big also having a high performance to protect people asset from stolen and helps to find lost objects.

REFERENCES Electronic devices and circuits , pearson education , by rico, beasley,bogart. Integrated electronics, jacob millman & halkias www.wikipedia.com www.talkingelectronics.com www.uspatents.com www.google.com

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