Metal detectors are devices that use electromagnetic fields to detect and signal the presence of metallic or ferromagnetic objects. Metal detectors vary in their effective operating ranges and the amounts and types of metals necessary to generate a signal. They may be fixed, as in the familiar airport walk-through detectors, or hand-held and portable. Uses include sport (finding coins, jewellery and artefacts), prospecting, industrial and security. Metal detectors have been used to identify metal objects placed into or upon patients either therapeutically, through injury or ingestion, or purely diagnostically. This article reviews the history of metal detection in the practice of medicine and provides an overview of the utility of metal detectors in current diagnostic practice. Non-diagnostic, medically related uses include scanning of hospital patients and visitors for weapons and of entrances to magnetic resonance imaging (MRI) centres to prevent flying metal objects and subsequent injury.[1]. The simplest form of a metal detector consists of an oscillator producing an alternating current that passes through a coil producing an alternating magnetic field. If a piece of electrically conductive metal is close to the coil, eddy currents will be induced in the metal, and this produces an alternating magnetic field of its own. If another coil is used to measure the magnetic field (acting as a magnetometer), the change in the magnetic field due to the metallic object can be detected. A metal detector is not an instrument that detects energy emissions from radioactive materials. A metal detector simply detects its presence and reports this. Metal detectors are fascination machines.
Simple Metal Detector Circuit Diagram and Workingelprocus
A metal detector is used to sense any existing metal which is nearby. A Metal detector is an electronic device which is used in many places like theatres, shopping malls, hotels, etc., to detect any metallic objects like knives, guns or any other explosives kept hidden within.
Metal detectors operate using electromagnetic induction by transmitting a magnetic field and analyzing changes induced in metal objects. The document describes the principle of operation, including how eddy currents are induced in metals, opposing the magnetic field. It provides a circuit diagram and discusses the beat-frequency oscillator design. Metal detectors have applications in security screening, construction, civil engineering, landmine detection, and archaeology. They are compact, simple to use, and can detect small metal targets.
This document describes the design and working of a low-cost metal detector circuit. It uses a Colpitts oscillator circuit with resistors, capacitors, transistors, diodes, an LED, coil, buzzer and battery. When the coil is brought near a metal object, it absorbs magnetic energy and causes the oscillator frequency to change. This triggers the final transistor to conduct, activating the buzzer and LED to indicate metal detection. The metal detector can be used to detect metallic objects for applications like food safety inspection and security systems.
This document describes the design and components of a simple metal detector circuit. It includes an introduction explaining how metal detectors work by detecting changes in a coil's magnetic field from nearby metals. The circuit uses a transistor as a Colpitts oscillator whose frequency shifts when metal is near the coil. Key components are listed along with explanations of their purpose and properties. Advantages of the simple design are portability and ability to detect metals, while limitations are low sensitivity and fixed capacitor values. Applications discussed include security screening and construction use to locate rebar or pipes.
Proximity sensors are contactless sensors that detect the presence or movement of nearby objects without physically touching them. They work by sensing electromagnetic fields (inductive), capacitance changes (capacitive), ultrasonic waves (ultrasonic), or infrared light (IR). Proximity sensors have a long service life since they have no moving parts, can detect objects in various environments and conditions, and are used in a wide range of applications including smartphones, industrial automation, and more. The ideal proximity sensor quickly and accurately detects objects without being affected by surface properties or environmental factors.
A light sensor detects ambient light levels and can include photoresistors, photodiodes, or phototransistors. It works by measuring changes in electrical resistance, voltage, or current caused by exposure to light. Light sensors have a wide range of applications including in street lights, cameras, alarms, and automatic lighting controls.
Simple Metal Detector Circuit Diagram and Workingelprocus
A metal detector is used to sense any existing metal which is nearby. A Metal detector is an electronic device which is used in many places like theatres, shopping malls, hotels, etc., to detect any metallic objects like knives, guns or any other explosives kept hidden within.
Metal detectors operate using electromagnetic induction by transmitting a magnetic field and analyzing changes induced in metal objects. The document describes the principle of operation, including how eddy currents are induced in metals, opposing the magnetic field. It provides a circuit diagram and discusses the beat-frequency oscillator design. Metal detectors have applications in security screening, construction, civil engineering, landmine detection, and archaeology. They are compact, simple to use, and can detect small metal targets.
This document describes the design and working of a low-cost metal detector circuit. It uses a Colpitts oscillator circuit with resistors, capacitors, transistors, diodes, an LED, coil, buzzer and battery. When the coil is brought near a metal object, it absorbs magnetic energy and causes the oscillator frequency to change. This triggers the final transistor to conduct, activating the buzzer and LED to indicate metal detection. The metal detector can be used to detect metallic objects for applications like food safety inspection and security systems.
This document describes the design and components of a simple metal detector circuit. It includes an introduction explaining how metal detectors work by detecting changes in a coil's magnetic field from nearby metals. The circuit uses a transistor as a Colpitts oscillator whose frequency shifts when metal is near the coil. Key components are listed along with explanations of their purpose and properties. Advantages of the simple design are portability and ability to detect metals, while limitations are low sensitivity and fixed capacitor values. Applications discussed include security screening and construction use to locate rebar or pipes.
Proximity sensors are contactless sensors that detect the presence or movement of nearby objects without physically touching them. They work by sensing electromagnetic fields (inductive), capacitance changes (capacitive), ultrasonic waves (ultrasonic), or infrared light (IR). Proximity sensors have a long service life since they have no moving parts, can detect objects in various environments and conditions, and are used in a wide range of applications including smartphones, industrial automation, and more. The ideal proximity sensor quickly and accurately detects objects without being affected by surface properties or environmental factors.
A light sensor detects ambient light levels and can include photoresistors, photodiodes, or phototransistors. It works by measuring changes in electrical resistance, voltage, or current caused by exposure to light. Light sensors have a wide range of applications including in street lights, cameras, alarms, and automatic lighting controls.
This document describes the components and design of a basic metal detector. It discusses the principles of electromagnetic induction that metal detectors use to detect nearby metals. It explains the main types of metal detectors as pulse induction, beat-frequency oscillator, and very low frequency. The document also provides the circuit diagram and components used in the metal detector project, including a 555 timer IC, coil, capacitors, and speaker. Application areas mentioned include archaeology, security screening, salvage work, and treasure hunting.
This document provides an overview of sensors. It defines a sensor as a device that measures a physical quantity and converts it into a signal. It gives examples of common sensors like infrared sensors used in hotels and taps, and photoelectric sensors used in street lights and automatic stairs. The document outlines the uses of sensors in various applications like cars, machines, aerospace, medicine and more. It concludes by describing ideal properties of sensors like being sensitive only to the measured property and not influencing it.
The document summarizes a student project on a light sensor circuit. It includes a list of group members, introduction to the concept of a light sensor using a light dependent resistor (LDR), circuit diagram, list of components including LDR, integrated circuit, variable resistor, resistance, transistor, diode, and relay. It describes how each component works and concludes with potential applications of the light sensor circuit including street lamps, alarm clocks, and burglar alarms.
The document describes the design and development of a live wire detector circuit. The circuit uses a CD4017 decade counter IC, LED, capacitor, battery and a probing wire. When the probing wire is brought near a live electric wire, capacitive coupling causes the counter to clock and the LED to flash, indicating the presence of a live wire. The frequency of flashing depends on the line frequency. The circuit can help detect hidden live wires in walls and prevent electric shock during renovation work. It was developed for safety to indicate potential electric wire hazards before drilling or nailing.
The document discusses light sensors, including their components, types, and applications. It describes how light sensors work by converting light energy into an electrical signal using a photocell. The main types of light sensors are photodiodes, photo resistors, and phototransistors. Light sensors are used in applications like street lamps, alarm clocks, cameras, and barcode scanners to detect light levels and presence.
This document discusses different types of sensors used in IoT applications. It describes resistive sensors like potentiometers, photoresistors, and thermistors. It also covers temperature sensors like thermocouples and RTDs. Other sensor types discussed include strain gauges, capacitive sensors, ultrasonic sensors, and MEMS sensors. For each sensor type, the document provides details on working principles, examples, and applications.
We provide you Project Temperature Sensors – Types.You can choose the best of your choice and interest from the list of topics we suggested. All new project ideas that are appearing focuses to improve the knowledge of Engineering students.
https://www.elprocus.com
Visit our page to get more ideas on Project Report Format for Final Year Engineering Students these ideas developed by professionals.
Elprocus provides free verified electronic projects kits around the world with abstracts, circuit diagrams, and free electronic software. We provide guidance manual for Do It Yourself Kits (DIY) with the modules at best price along with free shipping.
The document discusses sensors, defining them as devices that measure physical quantities and convert them into signals. It describes qualities of good sensors such as sensitivity and lack of influence on the measured property. Additionally, it covers common sensor types, errors, and measurement definitions like sensitivity, deviation, and resolution.
Land mines buried underground pose threats to lives and the economy. Detecting and removing them manually is dangerous and sometimes causes accidents. Robots can help detect land mines and other buried metals. The document describes a proposed robot that uses a metal detector based on electromagnetic induction to search for land mines and metals underground. When metal is detected, eddy currents are induced that generate a signal indicating the presence of metal.
The document describes a simple fire detection circuit using a thermistor. The circuit uses a potential divider configuration with a thermistor and resistor to sense temperature changes. When the temperature and thermistor resistance rises due to heat, the voltage drop across the resistor increases, turning on a transistor and activating a buzzer alert. This simple, low-cost circuit can be used for fire detection in homes, schools, industries, and research facilities.
This Presentation provides some basics of Sensors Technology.........
It gives few ideas to learn about sensors which are as normally used as electrical & electronics applications.......
Function generators are electronic test equipment that generate common waveforms like sine, square, and triangular waves over a wide frequency range. They are used to test and develop electronic equipment. Simple function generators generate waveforms by charging and discharging a capacitor with a constant current source, while more advanced arbitrary waveform generators can produce any digitally defined shape using direct digital synthesis techniques. Function generators provide important features like continuous tuning over a broad frequency band, modulation capabilities, and the ability to sweep output frequencies.
Sensors are devices that measure physical quantities and convert them into signals that can be read by observers or instruments. The document discusses several common sensors: infrared (IR) sensors, sound sensors, temperature sensors, and discusses their working principles and applications. It also provides details on using timers and integrated circuits like the 555 timer IC to process sensor output signals.
This article provides an introduction to the fundamental of Sensors and Transducers. It illustrates the different classifications of sensors and transducers. Explains capacitive, resistive and inductive transducers in brief. Also shows the examples under these types of transducers.
Temperature sensors measure temperature through electrical signals and come in various types. The most common types are thermocouples, resistance temperature detectors (RTDs), and thermistors. They can measure temperature through direct contact or non-contact methods and are used across many applications including heating/cooling, automobiles, medical devices, and more. RTDs are considered the most accurate as they have good accuracy, linearity, stability and repeatability compared to other sensor types like thermocouples and thermistors.
Opto-isolators or Opto-couplers, are made up of a light emitting device, and a light sensitive device, all wrapped up in one package, but with no electrical connection between the two, just a beam of light. Find different types of Opto couplers and its applications.
This document presents a low-cost fire alarm circuit that uses a thermistor as a heat sensor. The circuit consists of a thermistor, slide switch, LED, buzzer, batteries, transistors, resistors, variable resistor, and relay circuit. When heat is applied to the thermistor, its resistance decreases and the circuit activates the buzzer to sound an alarm. The fire alarm circuit provides protection at low cost for homes, warehouses, industries and other applications. It is a simple, efficient and portable design suitable for detecting fires and alerting users.
The document discusses various types of photosensitive devices that can convert light energy into electrical energy. It describes passive transducers like photoemissive, photoconductive cells and active photovoltaic transducers. Selenium cells are introduced as early photovoltaic devices that use the photovoltaic effect to generate voltage and current. Other active transducers discussed include photomultiplier tubes, photodiodes, and light dependent resistors. Various biomedical applications of photosensitive devices are also mentioned like pulse pickup, respiration monitoring, and blood oxygen detection.
This ppt explains Metal Detector Robotic Vehicle, student is provided with his/her authorized tag to swipe over the reader to record their attendance.
Edgefxkits.com has a wide range of electronic projects ideas that are primarily helpful for ECE, EEE and EIE students and the ideas can be applied for real life purposes as well.
http://www.edgefxkits.com/
Visit our page to get more ideas on popular electronic projects developed by professionals.
Edgefx provides free verified electronic projects kits around the world with abstracts, circuit diagrams, and free electronic software. We provide guidance manual for Do It Yourself Kits (DIY) with the modules at best price along with free shipping.
This document proposes a metal detection robot that can detect metals ahead of it and avoid collisions using ultrasonic sensors. The robot uses an Arduino Uno microcontroller board to control two DC motors via a motor driver chip and detect metals using a metal detector coil. Ultrasonic sensors help the robot detect and avoid obstacles to provide a safe metal detecting robot that can operate in hazardous environments.
This document describes the components and design of a basic metal detector. It discusses the principles of electromagnetic induction that metal detectors use to detect nearby metals. It explains the main types of metal detectors as pulse induction, beat-frequency oscillator, and very low frequency. The document also provides the circuit diagram and components used in the metal detector project, including a 555 timer IC, coil, capacitors, and speaker. Application areas mentioned include archaeology, security screening, salvage work, and treasure hunting.
This document provides an overview of sensors. It defines a sensor as a device that measures a physical quantity and converts it into a signal. It gives examples of common sensors like infrared sensors used in hotels and taps, and photoelectric sensors used in street lights and automatic stairs. The document outlines the uses of sensors in various applications like cars, machines, aerospace, medicine and more. It concludes by describing ideal properties of sensors like being sensitive only to the measured property and not influencing it.
The document summarizes a student project on a light sensor circuit. It includes a list of group members, introduction to the concept of a light sensor using a light dependent resistor (LDR), circuit diagram, list of components including LDR, integrated circuit, variable resistor, resistance, transistor, diode, and relay. It describes how each component works and concludes with potential applications of the light sensor circuit including street lamps, alarm clocks, and burglar alarms.
The document describes the design and development of a live wire detector circuit. The circuit uses a CD4017 decade counter IC, LED, capacitor, battery and a probing wire. When the probing wire is brought near a live electric wire, capacitive coupling causes the counter to clock and the LED to flash, indicating the presence of a live wire. The frequency of flashing depends on the line frequency. The circuit can help detect hidden live wires in walls and prevent electric shock during renovation work. It was developed for safety to indicate potential electric wire hazards before drilling or nailing.
The document discusses light sensors, including their components, types, and applications. It describes how light sensors work by converting light energy into an electrical signal using a photocell. The main types of light sensors are photodiodes, photo resistors, and phototransistors. Light sensors are used in applications like street lamps, alarm clocks, cameras, and barcode scanners to detect light levels and presence.
This document discusses different types of sensors used in IoT applications. It describes resistive sensors like potentiometers, photoresistors, and thermistors. It also covers temperature sensors like thermocouples and RTDs. Other sensor types discussed include strain gauges, capacitive sensors, ultrasonic sensors, and MEMS sensors. For each sensor type, the document provides details on working principles, examples, and applications.
We provide you Project Temperature Sensors – Types.You can choose the best of your choice and interest from the list of topics we suggested. All new project ideas that are appearing focuses to improve the knowledge of Engineering students.
https://www.elprocus.com
Visit our page to get more ideas on Project Report Format for Final Year Engineering Students these ideas developed by professionals.
Elprocus provides free verified electronic projects kits around the world with abstracts, circuit diagrams, and free electronic software. We provide guidance manual for Do It Yourself Kits (DIY) with the modules at best price along with free shipping.
The document discusses sensors, defining them as devices that measure physical quantities and convert them into signals. It describes qualities of good sensors such as sensitivity and lack of influence on the measured property. Additionally, it covers common sensor types, errors, and measurement definitions like sensitivity, deviation, and resolution.
Land mines buried underground pose threats to lives and the economy. Detecting and removing them manually is dangerous and sometimes causes accidents. Robots can help detect land mines and other buried metals. The document describes a proposed robot that uses a metal detector based on electromagnetic induction to search for land mines and metals underground. When metal is detected, eddy currents are induced that generate a signal indicating the presence of metal.
The document describes a simple fire detection circuit using a thermistor. The circuit uses a potential divider configuration with a thermistor and resistor to sense temperature changes. When the temperature and thermistor resistance rises due to heat, the voltage drop across the resistor increases, turning on a transistor and activating a buzzer alert. This simple, low-cost circuit can be used for fire detection in homes, schools, industries, and research facilities.
This Presentation provides some basics of Sensors Technology.........
It gives few ideas to learn about sensors which are as normally used as electrical & electronics applications.......
Function generators are electronic test equipment that generate common waveforms like sine, square, and triangular waves over a wide frequency range. They are used to test and develop electronic equipment. Simple function generators generate waveforms by charging and discharging a capacitor with a constant current source, while more advanced arbitrary waveform generators can produce any digitally defined shape using direct digital synthesis techniques. Function generators provide important features like continuous tuning over a broad frequency band, modulation capabilities, and the ability to sweep output frequencies.
Sensors are devices that measure physical quantities and convert them into signals that can be read by observers or instruments. The document discusses several common sensors: infrared (IR) sensors, sound sensors, temperature sensors, and discusses their working principles and applications. It also provides details on using timers and integrated circuits like the 555 timer IC to process sensor output signals.
This article provides an introduction to the fundamental of Sensors and Transducers. It illustrates the different classifications of sensors and transducers. Explains capacitive, resistive and inductive transducers in brief. Also shows the examples under these types of transducers.
Temperature sensors measure temperature through electrical signals and come in various types. The most common types are thermocouples, resistance temperature detectors (RTDs), and thermistors. They can measure temperature through direct contact or non-contact methods and are used across many applications including heating/cooling, automobiles, medical devices, and more. RTDs are considered the most accurate as they have good accuracy, linearity, stability and repeatability compared to other sensor types like thermocouples and thermistors.
Opto-isolators or Opto-couplers, are made up of a light emitting device, and a light sensitive device, all wrapped up in one package, but with no electrical connection between the two, just a beam of light. Find different types of Opto couplers and its applications.
This document presents a low-cost fire alarm circuit that uses a thermistor as a heat sensor. The circuit consists of a thermistor, slide switch, LED, buzzer, batteries, transistors, resistors, variable resistor, and relay circuit. When heat is applied to the thermistor, its resistance decreases and the circuit activates the buzzer to sound an alarm. The fire alarm circuit provides protection at low cost for homes, warehouses, industries and other applications. It is a simple, efficient and portable design suitable for detecting fires and alerting users.
The document discusses various types of photosensitive devices that can convert light energy into electrical energy. It describes passive transducers like photoemissive, photoconductive cells and active photovoltaic transducers. Selenium cells are introduced as early photovoltaic devices that use the photovoltaic effect to generate voltage and current. Other active transducers discussed include photomultiplier tubes, photodiodes, and light dependent resistors. Various biomedical applications of photosensitive devices are also mentioned like pulse pickup, respiration monitoring, and blood oxygen detection.
This ppt explains Metal Detector Robotic Vehicle, student is provided with his/her authorized tag to swipe over the reader to record their attendance.
Edgefxkits.com has a wide range of electronic projects ideas that are primarily helpful for ECE, EEE and EIE students and the ideas can be applied for real life purposes as well.
http://www.edgefxkits.com/
Visit our page to get more ideas on popular electronic projects developed by professionals.
Edgefx provides free verified electronic projects kits around the world with abstracts, circuit diagrams, and free electronic software. We provide guidance manual for Do It Yourself Kits (DIY) with the modules at best price along with free shipping.
This document proposes a metal detection robot that can detect metals ahead of it and avoid collisions using ultrasonic sensors. The robot uses an Arduino Uno microcontroller board to control two DC motors via a motor driver chip and detect metals using a metal detector coil. Ultrasonic sensors help the robot detect and avoid obstacles to provide a safe metal detecting robot that can operate in hazardous environments.
CBSE Class XII physics practical project on Metal detectorPranav Ghildiyal
This document is a project report submitted by Pranav Ghildiyal to his school, Kendriya Vidyalaya B.E.G, for the 2013-2014 academic year. The project is about the circuit diagram and working of a metal detector. It provides background information on the history and development of metal detectors from their early crude designs to modern portable devices. It describes the different types of metal detectors including Very Low Frequency, Pulse Induction, and Beat Frequency Oscillator detectors. Potential uses of metal detectors are also listed.
This document describes the design and construction of a metal detector. It includes:
- An introduction describing the motivation and scope of work.
- A literature review of previous metal detector designs.
- A theoretical background covering the electronic components used such as resistors, transistors, capacitors, oscillators, and ICs.
- Plans to design the power supply, display, switching and amplification circuits.
- Intentions to construct, test and evaluate the performance of the metal detector.
This document describes a metal detecting robot built on an 8051 microcontroller. The robot moves forward on a base mounted with an inductive metal detector. When metal is detected, a signal is sent to the microcontroller to stop the robot and activate a buzzer. It uses a 5V power supply with a 7805 regulator. The robot can be used for applications in robotics and automatic control systems.
This document provides an index and summaries of 100 transistor circuit designs. It begins with introductions on how transistors work and suggestions for building circuits using common components. The index lists various circuit categories and specific projects, many of which can be built with minimal components. The goal is to get readers experimenting with transistors through practical examples.
A lightning arrester, also known as a lightning conductor, is a device used to protect electrical power systems and telecommunications systems from damage caused by lightning strikes. It has a high voltage terminal connected to the power line and a ground terminal. When a lightning surge travels along the power line, the arrester diverts the current through itself to ground, usually by means of an arc across an air gap. Common types of lightning arresters include rod arresters, horn gap arresters, multi gap arresters, and various types using silicon carbide or metal oxide components. A horn gap arrester consists of two horn-shaped metal rods separated by a small air gap, connected to the power line through a resistance and choke coil to
This document discusses types of lightning arresters. It begins by explaining what lightning is and the mechanism of lightning discharge. There are two main types of lightning strokes: direct and indirect. Lightning arresters protect equipment by providing a low resistance path for surges to ground. The main types discussed are rod gap, horn gap, multigap, expulsion, and valve arresters. Valve arresters, which incorporate nonlinear resistors and spark gaps, are most effective and commonly used on high voltage systems above 66kV. The document concludes by mentioning IEC surge arrester testing standards.
This document summarizes types of lightning arresters, their classification, identification, standard ratings, and service conditions. There are three main types of arresters: expulsion, valve, and gapless metal-oxide. Arresters are classified into four classes based on their nominal discharge current and use: station, intermediate, distribution, and secondary. Arresters must be properly identified and can operate under normal conditions of temperature, radiation, altitude, and frequency, but may require special consideration under abnormal conditions.
This document discusses lightning arresters, including their purpose, types, classification, ratings, and service conditions. It describes three main types of arresters - expulsion, valve, and gapless metal-oxide. Arresters are classified into four classes based on their application and ratings. Standard ratings include nominal discharge current and voltage. Normal service conditions include temperature, radiation, altitude, and frequency ranges, while abnormal conditions require special consideration.
Instruction Manual for the Minelab X-TERRA 705 Metal Detector EnglishSerious Detecting
The document provides instructions for assembling and using the Minelab X-Terra 705 metal detector. It begins with assembling the detector parts including connecting the coil, shaft assembly, armrest assembly and connecting the control box. It then provides instructions for inserting batteries and an overview of the keypad and LCD display. The main sections cover turning the detector on, the detecting modes of Coin & Treasure and Prospecting, choosing discrimination patterns, setting ground balance and noise cancel, and begin detecting. It concludes with contact information for Minelab and a product specifications page.
This is a simple project for Induction Loop Vehicle Detector and Counter. It is very useful in counting car's and change its destination in tollbooth or parking area
Global metal detector industry 2016 market trends, analysis, research, growth...charudattrmoz
The document is a 130-180 page research report on the global metal detector market from 2016-2020. It analyzes the historic and current state of the market, and projects future growth. It examines the market segments based on product type, application, end users, and geographic distribution. It also outlines the major players, trends, technologies, production, and revenue of the metal detector market globally and regionally.
Instruction Manual Minelab Explorer SE Pro Metal Detector English LanguageSerious Detecting
The document provides quick start instructions for a metal detector:
1. Turn on the detector and press the "NOISE CANCEL" button to reduce electrical interference after 30 seconds.
2. You can now begin detecting for valuable coins, relics, gold, and jewelry.
3. The document also provides assembly instructions and explains how to insert batteries or recharge the battery pack.
The document summarizes a capsule metal detector project. It describes the need for detecting foreign metal bodies in medicines to provide safe products for consumers. It explains the main components of the metal detector including coils, oscillators, amplifiers, and a transformer based on Faraday's law of magnetic fields. A block diagram shows the data flow from the transmit oscillator through the search coil, receive amplifier, and buzzer to detect contaminated capsules.
A sensor is a device that detects or measures a physical property and records, indicates, or otherwise responds to it. Sensors are used in many everyday objects and applications, including elevators, lamps, cars, machines, medical equipment, manufacturing, and robotics. A metal detector uses an oscillator producing an alternating current through a coil to induce currents in nearby metal, generating its own magnetic field. This change in oscillation can then be used to detect the presence of metals.
If you are looking for great treasure hunting that starts with affordable yet durable equipment. Take a look at these best rated and well designed hybrid metal detectors.
Instruction Manual X-TERRA 305-505 Metal Detector English Language website49...Serious Detecting
The instruction manual provides directions for assembling an x-terra metal detector and instructions for its operation. It discusses connecting the coil, shaft assembly, armrest assembly, connecting the control box, inserting batteries, holding the detector, sweeping the coil, the control panel layout, turning the detector on, the LCD display, a simple detecting exercise, and example detections of ferrous and nonferrous targets.
study of lightning arrester ' working principal and working of lighning and construction of lightning arrester. and at the end what are the types of lightning arrester how these types are different from each other and what is their working principal and which is used mostly on 500kva substation.
THERMIONIC EMISSION
Emission this is the process whereby electrons are emitted (given out) from a substance.
Electron emission this is the process of liberating electrons from the metal surface.
WAYS OF EMITTING ELECTRONS
There are four ways of emitting electrons which are:
THERMIONIC EMISSION Is the process of emitting electrons by applying heat energy. OR is the discharge of electrons from the surfaces of heated materials.
PHOTO ELECTRIC EMISSION Is the process of emitting electrons by application of light energy.
HIGH FIELD EMISSION Is the process of emitting electrons by application of electric field.
SECONDARY EMISSION Is the process of producing electron by application of highest speed field.
Eddy current inspection uses electromagnetic induction to detect flaws in conductive materials. Alternating current in a probe coil generates a magnetic field that induces eddy currents in the material. Changes in conductivity due to flaws disturb the eddy currents, and are detected by measuring impedance changes in the coil. Eddy current probes come in different configurations and operate in absolute, differential, reflection, or hybrid modes to optimize detection of different flaw types or minimize interference from other factors.
Dielectric surface imaging using scanning electron microsopeVnAy Kris
this presentation includes the principle,construction of scanning electron microscope and the problems-solutions it faces when dielectric surfaces are imaged along with normal imaging
This document provides information about the photoelectric effect and photocells. It discusses Einstein's explanation of the photoelectric effect using Planck's quantum theory. It describes the characteristics of photoelectric effect including the effect of intensity, frequency, and photoelectric material. It then discusses Einstein's photoelectric equation and provides examples of calculating photon energies and electron kinetic energies related to the photoelectric effect. Finally, it discusses photocells and provides some common applications of photocells.
This document provides information about the photoelectric effect and photocells. It discusses Einstein's explanation of the photoelectric effect using Planck's quantum theory. It describes the characteristics and laws of photoelectric effect, including the effect of intensity, frequency, and photoelectric material on photoelectrons. It then explains the construction and working of a photocell, and provides some applications of photocells such as counting items on a conveyor belt or operating automatic doors. It concludes with some example problems calculating photon energies and photoelectron kinetic energies.
A cathode ray tube (CRT) is a sealed glass tube that contains an electron gun, phosphor coating, and magnets. When power is supplied to the CRT, the electron gun emits a beam of electrons that is bent by electric and magnetic fields and strikes the phosphor-coated screen, causing it to emit light. While CRTs are cheaper than other displays and have a wide viewing angle, they are bulky, consume more power than LCDs, and are prone to burn-in from displaying static images for long periods.
20200829-XII-Physics-Dual Nature of Radiation and Matter-1 of 7-Ppt.pptxManishMishra398080
This document provides an overview of electron emission and the photoelectric effect. It discusses four methods of electron emission: thermionic emission through heating, field emission using electric fields, photoelectric emission using light, and secondary emission from electron bombardment. For photoelectric emission, it describes Lenard's experimental setup and findings that photocurrent increases with light intensity but stopping potential is independent of intensity. Key topics covered include work function, the photoelectric effect in different metals, and how collector potential and light intensity affect photocurrent when frequency is fixed.
This document provides information on several types of microscopy techniques including scanning tunneling microscopy (STM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It discusses the principles, history, operation, and applications of STM for imaging at the nanoscale. SEM is described as using a beam of electrons to examine surface features, morphology, composition and generate images. TEM is explained as sending electrons through a sample to produce a projected image showing atomic arrangement.
Understanding Challenging Applications For Improved Metal Detection LoRes1Jonathan Richards
This document discusses product effect in metal detection and how it can hinder the detection of contaminants. It explains that some products like meat have high moisture content and conductivity, allowing eddy currents to form within the product in a metal detector's magnetic field, similar to how it occurs with metal contaminants. This interference is known as product effect. The document outlines several factors that influence product effect, such as moisture content, temperature, product size/shape, and packaging material. It also discusses how operating frequency is an important consideration, with lower frequencies reducing product effect but increasing noise interference.
This document discusses ultrasonics and its applications. It begins with an introduction to ultrasonic waves, including their properties and production methods such as magnetostriction and piezoelectric methods. Next, it describes common detection methods and applications of ultrasonics such as non-destructive testing to detect flaws in metals using ultrasonic beams. In closing, it provides a brief example of using ultrasonics for non-destructive testing to examine reflected echoes on an oscilloscope and detect flaws in materials.
Diploma sem 2 applied science physics-unit 5-chap-2 photoelectric effectRai University
This document summarizes the photoelectric effect and its laws and characteristics. It describes how the photoelectric effect was discovered and involves the emission of electrons from metal surfaces when light shines on it. The key laws are that photoelectric current is proportional to light intensity, there is a threshold frequency below which no emission occurs, and kinetic energy depends on frequency not intensity. Characteristics explained include how intensity affects current but not energy, and how increasing frequency increases energy. Einstein's model using photons is described along with the photoelectric equation. Applications of photocells are provided.
This document discusses the photoelectric effect and its explanation using Einstein's photon model of light. It defines the photoelectric effect, experimental setup, observations and results. It describes how photons eject electrons from metal surfaces, with kinetic energy determined by photon energy minus the metal's work function. It also discusses threshold frequency, work function, cut-off wavelength and frequency, and provides numerical examples to calculate these values.
This document discusses various sensors and transducers. It defines a transducer as a device that converts one form of energy to another, and a sensor as a transducer that detects a characteristic of its environment. It then provides details on different types of transducers and sensors, including antennas, Hall effect sensors, cathode ray tubes, sensors for ionizing radiation, electric current sensors, and proximity sensors. For each it discusses their definition, operating principle, applications and examples. The document is authored by several students and provides a comprehensive overview of key sensors and transducers.
Dual nature of radiation and matter class 12Lovedeep Singh
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Theory of metal detector by Amit sahu
1. 1
LIST OF FIGURES
FIG.NO. PAGE NO.
Fig:(1) Block diagram of a transmitter-receiver metal……………………………………………2
Fig:- (2) Circuit diagram of metal detector……………………………………………………….4
Fig:-(3) Concept of magnetic flux……………………………………………………………...…5
Fig:-(4) As transmitter current from the antenna generates the electromagnetic field …………...7
Fig:- (5) When any metal com…………………………………………………………………….8
Fig:- (6) This diagram of “perfect coupling” illustrates the general shape es within the detection
pattern of a search coil,…………………………………………………………………………….8
Fig:- (7) This illustration shows the location and approximate proportional size of the fringe
detection area………………………………………………………………………………………9
Fig:- (8) block diagram of regulated power supply……………………………………………….10
Fig:- (9) transformer input and output ……………………………………………………………11
Fi g:- (10.1) Bridge rectifier…………………………………………………………………,,,….11
Fig:-(10.2) Output: full-wave varying DC………………………………………………………..11
Fig: - (11) Transformer + Rectifier input and output………………………………………..........11
Fig:- (12) Transformer + Rectifier + Smoothing input and output ……………………………....11
Fig:- (13) Transformer + Rectifier + Smoothing + Regulator input and output………………….12
Fig :-(14) resistance and it’s circuit symbol………………………………………………………12
Fig:- (15) Capacitor and its circuit symbol…………………………………………………….....12
Fig:- (16) Transistor and it’s circuit symbol……………………………………………………...13
Fig:-(17)Diode and it’s circuit symbol………………………………………………..…………..13
Fig:- (18) Red (3mm)LED and it’s circuit symbol………………………………………….……13
Fig:- (19) 8 pin 555 timer…………………………………………………………………...…….14
Fig:-(20)Buzzer…………………………………………………………………………….……..14
Fig:-( 21) Soldering on strip board…………………………………………………………….....15
Fig:-( 22) Strip board layout………………………………………………………………...……15
2. 2
INTRODUCTION
Metal detectors are devices that use electromagnetic fields to detect and
signal the presence of metallic or ferromagnetic objects. Metal detectors vary
in their effective operating ranges and the amounts and types of metals
necessary to generate a signal. They may be fixed, as in the familiar airport
walk-through detectors, or hand-held and portable. Uses include sport (finding
coins, jewellery and artefacts), prospecting, industrial and security. Metal
detectors have been used to identify metal objects placed into or upon patients
either therapeutically, through injury or ingestion, or purely diagnostically. This
article reviews the history of metal detection in the practice of medicine and
provides an overview of the utility of metal detectors in current diagnostic
practice. Non-diagnostic, medically related uses include scanning of hospital
patients and visitors for weapons and of entrances to magnetic resonance
imaging (MRI) centres to prevent flying metal objects and subsequent
injury.[1]
. The simplest form of a metal detector consists of an oscillator
producing an alternating current that passes through a coil producing an
alternating magnetic field. If a piece of electrically conductive metal is close to
the coil, eddy currents will be induced in the metal, and this produces an
alternating magnetic field of its own. If another coil is used to measure the
magnetic field (acting as a magnetometer), the change in the magnetic field
due to the metallic object can be detected. A metal detector is not an
instrument that detects energy emissions from radioactive materials. A metal
detector simply detects its presence and reports this. Metal detectors are
fascination machines.
History and development, toward the end of the 19th century, many
scientists and engineers used their growing knowledge of electrical theory in an
attempt to devise a machine which would pinpoint metal. The use of such a
device to find ore-bearing rocks would give a huge advantage to any miner
who employed it. The German physicist Heinrich Wilhelm Dove invented. The
modern development of the metal detector began in the 1920s. Gerhard Fisher
had developed a system of radio direction-finding, which was to be used for
accurate navigation. The system worked extremely well, but Fisher noticed
that there were anomalies in areas where the terrain contained ore-bearing
rocks.
Fig:(1) Block diagram of a transmitter-receiver metal
5. 5
WORKING OF A METAL DETECTOR
The basic principle on which a metal detector works is that when electric
current passes through a coil, it produces a magnetic field around it. A metal
detector consists of an oscillator which produces alternating current. When this
alternating current passes through the transmit coil present in the metal
detector, a magnetic field is produced around it. Whenever an electrically
conductive metallic object comes in contact with the coil, it produces another
magnetic field around it. The metal detector contains another coil in its loop
called receiver coil, which detects the changes in the magnetic field caused due
to presence of the metallic object. The modern metal detectors are based on
any one of the three technologies, which are VLF (very low frequency), PI
(pulse induction) and BFO (beat-frequency oscillation).
The operation of metal detectors is based upon the principles of
electromagnetic induction. Metal detectors contain one or more inductor coils
that are used to interact with metallic elements on the ground. The single-coil
detector illustrated below is a simplified version of one used in a real metal
detector.
Fig: - (3) Concept of magnetic flux
A pulsing current is applied to the coil, which then induces a magnetic field
shown in blue. When the magnetic field of the coil moves across metal, such as
the coin in this illustration, the field induces electric currents (called eddy
currents) in the coin. The eddy currents induce their own magnetic field, shown
in red, which generates an opposite current in the coil, which induces a signal
indicating the presence metal.
(I):- Very Low Frequency (VLF) Technology
The most commonly used technology in metal detector is the VLF. Metal
detectors contain two sets of coils, namely, transmitter coil and receiver coil.
Electricity is passed through the transmitter coil to create a magnetic field. This
constantly pushes the electricity into the ground and pulls it back up. The
magnetic field so generated interacts with any metallic or conductive object
that comes in its way. The receiver coil passes the electric current whenever
6. 6
the metal detector passes over a conductive object. This amplifies and sends
the frequency of the current to the control box. Metal detectors, using VLF
technology, detect metals and determine the difference between different
types of metals and the depth at which they are located.
(II):- Pulse Induction (PI) Technology
PI technology uses a single coil, which plays the role of both the transmitter
and receiver. In some cases, it can make use of two or three coils also. Short
bursts or pulses of current are passed through the coil to generate a short
magnetic field. The end of each pulse results in the magnetic field reversing its
polarity suddenly and then collapsing. This, thus, creates electrical spikes
lasting for a short period. As soon as the spikes and magnetic field collapse,
another current, known as reflected pulse, runs through the coil which again
lasts for an extremely short period.
When a metal detector detects a metallic or conductive object, the reflective
pulse lasts for a longer duration. The reason behind this is that the pulse sent
by the metal detector produces an opposite magnetic field, causing the
reflective pulse to last longer. The metal detector monitors the spikes and
reflected pulses and sends the signals to the device called integrator. This
integrator reads, amplifies and converts the signals to direct current. The audio
circuit connected produces a tone indicating the presence of a metal or metallic
object.
(III):-Beat Frequency Oscillator (BFO) Technology
BFO uses two coils of wire just like VLF technology. One coil is connected in
the control box of the device, while the other is situated in the search end. The
coil in the control box is smaller than the one in the search end. Both are
connected to the oscillators that send thousands of electric pulses in a single
record. When pulses pass through each coil of wire, radio waves are created
that are collected by a receiver located in the control box.
On the frequency of the radio waves, the receiver creates audible tones.
When the metal detector passes over a metal or metallic object, the electric
current passing through the coil of the search end creates a magnetic field,
which in turn creates another magnetic field around the metallic objects. The
magnetic field interferes with the radio waves and causes a change in the
tones produced by the receiver. Hence, the metal detector beeps up.
How Metal Detectors Work:
A Simple Explanation We don't need to
understand all the science of how a metal
detector finds various metals. You can find
coins, rings, jewelry, gold, relics, artifacts, small
buried caches and even deep treasures without
knowing scientifically how a metal detector
works. Look at this simple illustration:
Illustration 'A' shows a typical metal detector
user. He has followed the instructions supplied
by the manufacturer and has his metal detector turned on. After testing his
7. 7
detector on some surface targets (coins) to make sure it is working, he now
starts searching for buried coins and treasures.
Notice the "red" signal pattern being
transmitted from the search coil into the ground.
(Note: we have enlarged the illustration of the
signal pattern for easier understanding). As long as
the signal entering the ground does NOT come in
contact with metal, there will be no audio signal, no
flashing light, no vibration, nothing will happen.
Illustration 'B' shows what happens when the
detector user's metal detector search pattern comes
in contact with metal objects, in this case both
shallow and deep coins. When the search pattern
touches metal it interrupts the transmitted signal
and this interruption or disturbance of the search
pattern will cause the metal detector to alert the detector user (you) with an
audio signal, usually a distinct loud sound. In some cases flashing or blinking
lights will accompany the audio signal.
Types of detecting:-
(1)Eddy Currents Secondary Electromagnetic Field Generation
Whenever metal comes within the detection pattern, electromagnetic field
lines penetrate the metal’s surface. Tiny circulating currents called “eddy
currents” are caused to flow on the metal surface as illustrated in the figure on
the facing page. The power or motivating force that causes eddy currents to
flow comes from the electromagnetic field itself. Resulting power loss by this
field (the power used up in generating the eddy currents) is sensed by the
detector’s circuits. Also, eddy currents generate a secondary electromagnetic
field that, in some cases, flows out into the surrounding medium. The portion
of the secondary field that intersects the receiver winding, causes a detection
signal to occur in that winding. Thus, the detector alerts the operator that
metal has been detected.
Fig:-(4) As transmitter current from the antenna generates the electromagnetic field, detection
patter (dotted lines) is the area within which Metal detection occurs. Mirror-image pattern atop
coil is not used.
8. 8
(2)Electromagnetic Field Distortion
The detection of non-conductive iron (ferrous) minerals takes place in a
different manner. When iron mineral comes near and within the detection
pattern, the electromagnetic field lines are redistributed, as shown in the figure
on the following page. This redistribution upsets the “balance” of the
transmitter and receiver windings in the search coil, resulting in power being
induced into the receiver winding. When this induced power is sensed by the
detector circuits, the detector alerts its operator to the presence of the iron
mineral. Iron mineral detection is a major problem for both manufacturers and
users of metal detectors. Of course, the detector of iron mineral is welcomed
by a gold hunter who is looking for black magnetic sand which can often signal
the presence of placer metal. On the other hand, the treasure hunter, who is
looking for coins, jewelry, relics, gold nuggets, etc., usually finds iron mineral
detection a nuisance.
Fig:- (5) When any metal comes within the detection pattern of a search coil, eddy currents
flow over its surface, resulting in a loss of power in the electromagnetic field, which the
detector’s circuits can sense.
(3)Salt Water Detection
Salt water (wetted salt) has a disturbing effect upon the electromagnetic
field because salt water is electrically conductive. In effect, salt ocean water
“looks like” metal to some detectors! Fortunately manufacturers are able to
design detectors capable of “ignoring” salt water.
Fig:- (6) This diagram of “perfect coupling” illustrates the general shape of a detection
pattern that occurs when the electromagnetic field from a search coil penetrates earth or any
other nearby object.
9. 9
(4)Fringe Area Detection
Fringe area detection is a phenomenon of detection, the understanding of
which will result in your being able to discover metal targets to the maximum
depth capability of any instrument. The detection pattern for a coin may
extend, say, one foot below the search coil. The detection pattern for a small
jar of coins may extend, perhaps, two feet below the search coil as illustrated
in the drawing on the facing page. Within the area of the detection pattern, an
unmistakable detector signal is produced.
Fig:- (7) This illustration shows the location and approximate proportional size of the fringe
detection area in which faint target signals from around the outer edges of a normal detection
pattern can be heard.
Types of Metal
The sensitivity of a metal detector is not the same for all types of metal. For
simplicity, we tend to categorize all metals into three types:
• Ferrous:
Any metal that can easily be attracted to a magnet (Steel, iron, etc.).
Typically the easiest metal to detect and usually the most common
contaminant.
• Non-Ferrous:
Highly conductive non-magnetic metals (copper, aluminum, brass, etc.)
When inspecting dry products these metals produce almost the same signal
size as ferrous due to the fact that they are good conductors. When inspecting
wet products, de-rate the sphere size by at least 50%.
• Non-Magnetic Stainless Steel:
High quality 300 series stainless steels (Type 304, 316). These are always
the most difficult metals to detect due to their poor electrical conductive
qualities and by definition are have low magnetic permeability. When
inspecting dry products a stainless sphere will have to be 50% larger than a
ferrous sphere to produce the same signal size. When inspecting wet products
a stainless sphere would have to be 200 to 300 % larger than a ferrous sphere
to produce the same signal size.
10. 10
POWER SUPPLY
Types of Power Supply
There are many types of power supply. Most are designed to convert high
voltage AC mains electricity to a suitable low voltage supply for electronic
circuits and other devices. A power supply can by broken down into a series of
blocks, each of which performs a particular function. For example a 12V
regulated supply:
Fig :-(8) block diagram of regulated power supply
Each of the blocks is described in more detail below:
• Transformer - steps down high voltage AC mains to low voltage AC.
• Rectifier - converts AC to DC, but the DC output is varying.
• Smoothing - smoothes the DC from varying greatly to a small ripple.
• Regulator - eliminates ripple by setting DC output to a fixed voltage.
Transformer only
Fig:- (9) transformer input and output
The low voltage AC output is suitable for lamps, heaters and special AC
motors. It is not suitable for electronic circuits unless they include a rectifier
and a smoothing
Bridge rectifier
A bridge rectifier can be made using four individual diodes, but it is also
available in special packages containing the four diodes required. It is called a
full-wave rectifier because it uses the entire AC wave (both positive and
negative sections). 1.4V is used up in the bridge rectifier because each diode
uses 0.7V when conducting and there are always two diodes conducting, as
shown in the diagram below. Bridge rectifiers are rated by the maximum
current they can pass and the maximum reverse voltage they can withstand
(this must be at least three times the supply RMS voltage so the rectifier can
11. 11
withstand the peak voltages). Please see the Diodes page for more details,
including pictures of bridge rectifiers.
Fig:- (10.1) Bridge rectifier
Alternate pairs of diodes conduct, changing over
the connections so the alternating directions of
AC are converted to the one direction of DC.
Fig:-(10.2) Output: full-wave varying DC
Transformer + Rectifier
Fig: - (11) Transformer + Rectifier input and output
The varying DC output is suitable for lamps, heaters and standard motors. It
is not suitable for electronic circuits unless they include a smoothing capacitor.
Transformer + Rectifier + Smoothing
Fig:- (12) Transformer + Rectifier + Smoothing input and output
12. 12
The smooth DC output has a small ripple. It is suitable for most electronic
circuits.
Transformer + Rectifier + Smoothing + Regulator
Fig:- (13) Transformer + Rectifier + Smoothing + Regulator input and output
The regulated DC output is very smooth with no ripple. It is suitable for all
electronic circuits.
Resistors Function:-
Resistors restrict the flow of electric current, for example a resistor is
placed in series with a light-emitting diode (LED) to limit the current passing
through the LED.
Example: Circuit symbol:
Fig :-(14) resistance and it’s circuit symbol
Capacitors Function:-
Capacitors store electric charge. They are used with resistors in
timing circuits because it takes time for a capacitor to fill with charge. They are
used to smooth varying DC supplies by acting as a reservoir of charge. They
are also used in filter circuits because capacitors easily pass AC (changing)
signals but they block DC (constant) signals.
Example: Circuit symbol:
Fig:- (15) Capacitor and its circuit symbol
13. 13
Transistor:-
Transistor transfers a signal from a low resistance to high resistance.
‘Trans’ means the signal transfer of the device. ‘Istor’ classified it as a solid
element in the same general family of resistor. A transistor is a semiconductor
device used to amplify and switch electronic signals and power. Transistor is a
“current” operated device which has a very large amount of current (Ic) which
flows without restraint through the device between the collector and emitter
terminals. But this is only possible if a small amount of biasing current (Ib) is
present in the base terminal of the transistor making the base to act as a
current control input. The symbol hfe or sometimes referred to as Beta (β) is
actually the ratio of these two currents (Ic/Ib) and is described as the DC
Current Gain of the device.
Fig:- (16) Transistor and it’s circuit symbol
Diodes Function:-
Diodes allow electricity to flow in only one direction. The arrow of the
circuit symbol shows the direction in which the current can flow. Diodes are the
electrical version of a valve and early diodes were actually called valves.
IN4001 diode used in the project.
Example: Circuit symbol:
Fig:-(17)Diode and it’s circuit symbol
Light Emitting Diodes (LED’s):-
LED is a solid state light source .it is a low power device and fast on off
switching.LEDs emits light when an electric current passes through them.
Example: Circuit symbol:
Fig:- (18) Red (3mm)LED and it’s circuit symbol
14. 14
555 Timer Circuit:-
The 555 timer IC is an integrated circuit (chip) used in a variety of timer,
pulse generation, and oscillator applications. The 555 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.
Fig:- (19) 8 pin 555 timer
The 8-pin 555 timer must be one of the most useful ICs ever made and it
is used in many projects. With just a few external components it can be used
to build many circuits, not all of them involve timing.
A popular version is the NE555 and this is suitable in most cases where a
'555 timer' is specified. The Low power versions of the 555 are made, such as
the ICM7555, but these should only be used when specified (to increase
battery life) because their maximum output current of about 20mA (with a 9V
supply) is too low for many standard 555 circuits. The ICM7555 has the same
pin arrangement as a standard 555.
The circuit symbol for a 555 (and 556) is a box with the pins arranged to
suit the circuit diagram: for example 555 pin 8 at the top for the +Vs supply,
555 pin 3 outputs on the right. Usually just the pin numbers are used and they
are not labeled with their function.
The 555 and 556 can be used with a supply voltage (Vs) in the range 4.5 to
15V (18V absolute maximum).
Alarm:-
The most common alarm is a
flashing beacon, activated by the
metal detector output relay. A siren,
horn, or bell may also be used, with
or without the beacon. Other
commonly used alarm devices are
buzzers; flag drop markers, paint
spray markers, and flashing.
Fig:-(20)Buzzer
15. 15
Strip board:-
Strip board has parallel strips of copper track on one side. The tracks are
0.1" (2.54mm) apart and there are holes every 0.1" (2.54mm).
Strip board is used to make up permanent, soldered circuits. It is ideal for
small circuits with one or two ICs (chips) but with the large number of holes it
is very easy to connect a component in the wrong place. For large, complex
circuits it is usually best to use a printed circuit board (PCB) if you can buy or
make one. Strip board requires no special preparation other than cutting to
size. It can be cut with a junior hacksaw, or simply snap it along the lines of
holes by putting it over the edge of a bench or table and pushing hard, but
take care because this needs a fairly large force and the edges will be rough.
You may need to use a large pair of pliers to nibble away any jagged parts.
Avoid handling strip board that you are not planning to use immediately
because sweat from your hands will corrode the copper tracks and this will
make soldering difficult. If the copper looks dull, or you can clearly see finger
marks, clean the tracks with fine emery paper, a PCB rubber or a dry kitchen
scrub before you start soldering.
Fig:-( 21) Soldering on strip board
Strip board layout:-
Fig:-( 22) Strip board layout
16. 16
Salient Features:-
• Auto setting.
• Lowest False Alarm Rates.
• Low Power Consumption.
• Easy to Operate.
• High Reliability, long life performance.
• High Sensitivity and High Accuracy.
• Detects all metals including non magnetic Stainless Steel.
• Totally indigenous. Spare parts and maintenance readily available.
• Audio / Visual alarm on Detection.
• High Sensitivity for maximum penetration.
• Detects all metals.
•
Applications:-
• Detects all metals.
• Identifies metallic objects by speaker sound and needle movement.
• Detection of weapons such as knives and guns, especially at airports,
malls, geophysical prospecting, archaeology and treasure hunting.
• Airport and Building Security.
• Archaeological exploration.
• Geological research.