How to make a sensitive metal detector with your own hands and what circuit of this device is most popular among craftsmen? Metal detectors are electronic induction devices, the main task of which is to detect metal objects located in a neutral or weakly conducting environment - such as soil, water, walls, wood.
The device has a search coil, in which, when turned on, an electromagnetic field is generated that spreads around. With its help you can explore the ground, stones, water, trees and air. The electromagnetic field created by the search coil contributes to the formation of eddy currents on the surface of metals that fall within the range of the device.
If eddy currents occur, the metal object's own counter electromagnetic field is created, which reduces the power of the electromagnetic field created by the search coil. This is recorded by the electronic circuit of the device. After processing the received information, the metal detector sends a signal that a metal object has been detected.
Cheap models of metal detectors differ from expensive ones only in the methods of emitting radio waves and methods of capturing, processing and decoding secondary signals. More expensive devices are able to determine with a certain degree of probability which metal has been detected even before it is extracted. The depth of the object and some other parameters can also be determined.
Treasure hunters often wonder whether it is possible to make at least a simple metal detector at home. Many of them would like to make the device themselves. There are craftsmen who are trying to somehow improve a ready-made metal detector, but there are also treasure hunters who are looking for treasures with homemade inventions. However, do-it-yourself devices for searching for hidden objects are usually used only for finding and collecting scrap metal. For such work, the simplest device that can easily catch large metal objects is sufficient. Such seekers are usually not interested in small metal objects.
Even if you didn’t succeed in making a metal detector with your own hands at home, the experience gained during the experiment will also be useful. After reading specialized literature and studying device diagrams and operating principles, it will not be difficult to choose a good metal detector made in an industrial environment.
To create a metal detector at home, improvised means alone are not enough. To do this, you need to have some experience in radio electronics, good skills in working with diagrams and drawings, as well as certain equipment. You can try to assemble a device for searching for metal objects yourself, starting from the circuit and ending with the search coil. You can also purchase a kit to create a metal detector.
How to make a simple metal detector without special equipment with your own hands according to the diagram:
♦ DIAGRAMS AND STEP-BY-STEP MASTER CLASS ON MANUFACTURING A “BUTTERFLY” METAL DETECTOR WITH YOUR OWN HANDS
- click on the photo and expand the step-by-step instructions
♦ VIDEO LESSONS
The dream of finding treasure is increasingly being replaced in our time by a more realistic program of searching for precious metals in a natural or artificial environment.
In modern conditions it is very important to find and extract valuable materials, who turned out to be among the waste, or in another uncontrolled environment.
Equipment is an important component of such search technology.
The search and extraction of gold and valuable metals from waste, garbage, in the natural environment is part of the recycling strategy, a technology for the effective processing of used materials, including.
Searching for them in the ground or in masses of industrial and other waste not only requires the use of equipment, but also stimulates its improvement. Are being created devices of different levels and specializations. There is interest in such equipment among amateurs and enthusiasts of searching for valuable metals.
A metal detector is the most important tool for manually searching for metals in a chaotic natural or artificial environment.
Using such a device, you can search not only for silver, but also for silver and other precious metals.
Device principle any metal detector based on electromagnetic effects.
Here's how typical metal detecting technology works:
- Device creates an electromagnetic field.
- Metal an object, secretly located in a foreign environment, affects such a field when falls within its sphere of influence.
- Device detects the impact of an object on the electromagnetic field and signals this.
A large number of metal detector models operate precisely on this principle.
Technical differences in such equipment make it possible to obtain more complete information about the fact of detecting a metal object, for example:
- estimate the mass of the find;
- obtain data on the shape, size and configuration of an object;
- specify the location, including depth.
There is a lot of information on the Internet about metal detectors of varying complexity and design. There you can also refresh your memory about the theory of the electromagnetic field, studied at school.
The simplest, primitive metal detectors (usually these are homemade designs for searching for gold, silver and other metals by amateur enthusiasts) assembled from ready-made devices and products operating using electromagnetic effects.
Many are familiar with the primitive, but quite workable circuit of a metal detector, in which an electromagnetic field creates a pulse element of a conventional calculator.
Reaction generated field on detected metal objects picks up the simplest household radio. The signal about such a find is audible, quite distinct and understandable.
More complex amateur and professional metal detecting devices retain the logical basis of the technology in the form of three components:
- electromagnetic field generator;
- sensor of changes in this field;
- equipment for assessing detected anomalies, signaling this.
Devices of different levels of complexity and functional potential can be divided into groups. Classification based on professionalism and user specializations – one of the generally recognized:
- amateur equipment, assembled by hand and used as a hobby tool or by beginners in metal detecting;
- semi-professional equipment necessary for enthusiastic amateurs and fanatics;
- professional metal detectors for those constantly working in this field;
- special devices for metal detectors in difficult conditions - at depth, under water, with the release of precious metals.
The distribution of search equipment is such that many devices of this type can be purchased at gardening and country supply stores.
A device for searching and detecting metal is needed not only for recycling, but also for searching for artifacts and treasures. Numerous security systems for everyone well-known frames - one of the technology versions metal search. The settings of these frames are focused on searching for weapons and similar dangerous objects.
Coil
A very important node metal detecting equipment – reel or frame. This is most often a winding of a special configuration, the task of which is to form an electromagnetic field and capture its reaction to the detection of a metal body foreign to the search environment.
In most designs the coil is placed on a long rod– a handle to move it near the search area.
For amateur production of reels, frames of the most popular types are sold. The easiest way to make such a purchase is in an online store.
Many lovers make the coil frames yourself. This is done for reasons of cost savings or in the hope of obtaining a better-quality instrument of the author's design.
For this, improvised means are used– plastic products, plywood and even filling the assembled winding with construction foam.
The search operator or treasure hunter strives to find the most effective technique for working with a metal detector, choosing the desired operating modes of the electronics and the correct techniques for manipulating the coil.
Electronic circuit
The logical element of a metal detector is an electronic circuit. She performs many functions:
- The first task of this component is in creating an electromagnetic signal of the desired format, which is converted into a field using a coil.
- The second task of the electronic circuit is analysis of field changes captured by the frame, their processing.
- The third task is giving an informing signal to the operator– sound, light, indications of indicators and instruments.
It is best if anyone who wants to assemble an electronic circuit has knowledge of amateur radio or electronic technology. Such a master can not only assemble the required circuit, but also change and improve the design.
Many electronic devices are quite simple, Even a beginner can assemble them. The resulting device will be operational without configuration if the assembler exactly followed the recommendations of the developer of such a circuit.
How to make "Pirate" yourself?
One of the most popular models of metal detectors designed for homemade amateur production is the “Pirate”.
This name, containing abbreviated details of its device and the developers' website, wittily reflects the romance of searching for precious metals.
Here the main advantages of this model:
- simplicity of device and assembly;
- low cost of parts and materials;
- sufficient operating parameters;
- recognized convenience for beginners.
The electronic circuit of this model does not require programming. In "Pirate" details available to everyone are used, a correctly assembled circuit is fully operational.
Design and operating principle
The design and layout of the “Pirate” metal detector is traditional for equipment of this kind. It is a rod, at the lower end of which there is a coil, and in the upper part – electronic unit with battery.
The location of the electronic unit should leave room for comfortable holding of the rod by hand.
Some craftsmen prefer that the sound signal from the device is supplied not by a speaker, but by headphones. In this case, the headphone cable departs from the electronic unit.
The technology of operation of the device is pulsed. This allows us to provide very good sensitivity indicators for this class of equipment. Below is a diagram of an electronic unit on microcircuits. 
A similar circuit can be assembled using transistors instead of microcircuits. This version may require additional settings, available only to experienced radio technicians. This is why the transistor circuit is used less frequently.
Materials, parts and blanks
In addition to the details and precision indicated on the circuit diagram of the electronic unit, for assembly metal detector for gold and other metals you will need to prepare some materials and blanks:
- a ready-made board for assembling an electronic circuit or foil material for making it yourself;
- power source in the form of any combination of batteries or batteries with a total voltage of 12V;
- enamel wire with a cross section of 0.5 - 0.6 mm for making a coil;
- stranded copper wire for connections with a cross-section of at least 0.75 sq. mm;
- housing for the electronic unit - a plastic container of a suitable size;
- a fairly strong plastic pipe for the rod;
- coil winding frame;
- consumables - solder, heat-shrinkable casing, electrical tape, screws and fasteners, adhesives and sealants.
It is best to make a printed circuit board for assembling an electronic circuit based on designs presented on the Internet.
Below is one of these samples, suitable for assembling electronics on microcircuits.
The manufacture of the board is carried out by amateurs of homemade electronics, and even then not all of them. Most people who want to create a metal detector themselves prefer to buy such a part.
To assemble the coil you will need a frame or frame, does not contain metal elements. An amateur craftsman can make such a frame from plywood, plastic, or select similar parameters from ready-made plastic products, for example, dishes. The frame can be purchased ready-made or made independently
Recommended coil parameters– 25 turns of enamel wire with a diameter of 0.5 mm on a mandrel with a diameter of 190-200 mm. An increase in diameter by 30% will lead to an increase in the sensitivity of the device, provided that the number of turns is reduced to 20-21.
The plastic frame for the coil is one of the most common metal detector parts on sale.
The technology for manipulating the coil is such that this very fragile unit can suffer from impacts from uneven ground, stones, and sharp objects. To avoid this the coil on the frame is covered from below with a plastic plate. This plate not only protects the reel, but also ensures that it glides through tall grass. The search becomes more intense.
Assembly procedure and design
To successfully assemble a metal detector It is best to follow this procedure:
- manufacture of printed circuit boards and assembly of electronic circuits;
- choosing a suitable plastic container for it and completing the assembly of the electronic unit;
- coil manufacturing;
- manufacturing a rod of a convenient shape and attaching an electronic unit and coil to it, making connections for an electronic circuit.
Although the order of assembly is not fundamental. For those who manufacture a device for constant long-term work in the field of searching for non-ferrous metals and subsequent recycling (processing for reuse), ease of use is an important factor.
In this case, elaboration of the shape of the bar and the layout of the main elements of the apparatus becomes a key factor. Thus, a serious design phase appears in the creation of the device.
It is best to perform this stage of work using life-size modeling. Such modeling can be done using wooden parts of suitable shape, for example:
- shovel handle;
- plywood pieces of the desired shape;
- scraps from;
- temporary fasteners made from pieces of wire, nails and ropes.
Having made sure that the assembled model of the device will be sufficiently functional and convenient, you can begin the final assembly. Ready-made device, usually, does not require configuration, it is completely ready to work. You can start searching for metal by choosing the desired level of sensitivity and the correct tactics for manipulating the coil.
Assemblers who need to assemble their apparatus as quickly as possible can use ready-made sets of parts.
Purchasing such a kit allows you to significantly simplify the production of “Pirate”. There is one of the proposals.
Users of the “Pirate” metal detector who have skills in amateur radio modify the design of this device. That's just several directions such improvements:
- Manufacturing coils with unusual parameters– in size, from special materials, for example, twisted pair cable.
- Arrangement of additional functional systems, for example, indicating the degree of battery discharge.
- Manufacturing models for underwater work.
- Add-ons electronic circuit, allowing to distinguish between metals(creating a discrimination function).
A simple, inexpensive and reliable metal detector “Pirate” works properly in a variety of conditions.
Homemade metal detector - pros and cons
Cheapness, basic advantage self-production of any products, relevant for a metal detector. Here are some others dignity for a homemade device:
- best match to search technology for beginners;
- the ability to create a device with a completely individual shape, design and configuration;
- the pleasure of making an effective, efficient device yourself.
Like any amateur-made device, a metal detector not without some drawbacks.
Here are the features of the “Pirate” model that users note:
- energetic charge consumption power batteries;
- no discrimination, that is, precise sensitivity to ferrous, non-ferrous and precious metals;
- limited compared to expensive models sensitivity.
Despite its shortcomings, the Pirate model is very popular. This is explained by the simplicity of homemade production and the high performance of an inexpensive device.
Recycling experts believe that the discrimination capabilities of a metal detector are not of great importance. All metals found are so valuable that recycling them is always justified. Focusing on finding gold requires not only equipment, but also considerable experience, accompanying knowledge and, of course, Good luck.
Video on the topic
The video provides a detailed guide to making and assembling the Pirate metal detector with your own hands:
Conclusion
When the metal detector is ready, you can begin work. You need to be aware that not even the most advanced apparatus will allow you to find only golden hidden objects.
A metal detector will help you find valuable metal, and it is very likely that it will be gold. It is best if the future metal and gold seeker has a realistic understanding of search techniques.
Many features of the operation of finished equipment are very important for those who develop and assemble their own models. You need to have an idea of the technology in advance with such equipment - this is precisely the basis of its high-quality design.
The success of finding gold increases with experience. Here most important elements such experience:
- the correct choice of metal detector design and high-quality manufacturing of it yourself;
- ability to correctly select a search site;
- ability to use the full potential of a metal detector;
- choosing the right search technology in different conditions;
- modernization of the metal detector.
Properly assembled and debugged equipment will always help in the search for gold, and this valuable metal will definitely be found.
In contact with
Today, there are many different ideas on the Internet that allow you to make a metal detector with your own hands at home. Some of them require certain skills in working with electrical appliances, soldering and understanding of simple electrical circuits, while some do not require any knowledge in these areas to create. However, there are many non-working, fake methods floating around the Internet, captivating with their simplicity and accessibility. It is very easy for an inexperienced person to fall for the bait of deceivers - to spend time and effort on making a device that is obviously not working and lose all interest in it. But don’t be discouraged, then readers of “” will be provided with an interesting and really working scheme for creating a homemade metal detector!
Idea No. 1 – Discs in action!
Surely you have already seen or heard that you can make the simplest metal detector yourself using a CD and DVD disc, as shown in the photo. The scheme is quite simple and does not require any professional tools or skills.
This instruction is the most popular due to the availability of the necessary components and the ease of assembly; you just need to connect a couple of wires and the crown together and the device is ready. At the same time, the characteristics of this device are attributed to be quite good - it finds a coin at a distance of 25-30 cm, which is quite enough for searching for coins and treasures. However, unfortunately, this instruction is fake.
The fact is that the metal detector itself is a rather complex device; its operation is based on several physical phenomena at once. Therefore, a calculator and a pair of disks cannot even remotely replicate its operating principle, no matter what the creators of such instructions claim, who sometimes write that they even find treasures with the help of such homemade products.
It is very easy to understand that you are being deceived even without knowledge of the laws of physics. The wires from the headphones that need to be attached to the disk do not actually contact it in any way, since the copper is under a layer of varnish insulation, which must be removed by firing and labor-intensive cleaning of carbon deposits; of course, none of the authors of the instructions does this in their devices . Consequently, the headphones are simply not connected to any circuit, and there can be no talk of any work, much less metal detecting.
A real metal detector operates on the basis of an induction balance; its design must have at least one coil of copper wire. When a metal object enters the field of the coil, its characteristics or the received signal, depending on the design, change. These changes are recorded and amplified by the circuit, and also displayed in a form understandable to humans, usually by means of sound signals.
Video instructions for assembling a metal detector from disks
Idea No. 2 – Metal detector according to the “Pirate” scheme
This is a scheme that has been tested by many DIYers and allows you to achieve good results. It contains two microcircuits, so you will have to make a small printed circuit board or assemble the device on a breadboard. But don’t be alarmed, anyone can make this option if they put in the necessary effort. Below is an electronic circuit diagram of the device and a printed circuit board for it.
The coil is made of enameled copper wire with a diameter of 0.5 mm. Winding should be done on a frame with a diameter of 200-260 mm, the number of turns from 21 to 25. For reliability, it is better to install the coil in a protective plastic casing, which can then be attached to a handle made of PVC pipes.
After assembling the metal detector, it must be checked. The procedure for use is as follows: turn on the device away from metal objects for about 30 seconds so that its operation is more stable, then rotate the variable resistor knob for coarse and fine adjustment, you need to achieve rare clicks. When metal enters the action area, you will hear a characteristic sound.
Below is a detailed video assembly instruction, which clearly shows all the stages of creating a homemade metal detector.
I can say without a doubt that this is the simplest metal detector I have ever seen. It is based on just one TDA0161 chip. You won't need to program anything - just assemble it and that's it. Another great difference is that it does not make any sounds during operation, unlike a metal detector based on the NE555 chip, which initially beeps unpleasantly and you have to guess the metal found by its tone.
In this circuit, the buzzer starts beeping only when it detects metal. The TDA0161 chip is a specialized industrial version for induction sensors. And metal detectors for production are mainly built on it, giving a signal when metal approaches the induction sensor.
You can purchase such a microcircuit at -
It is not expensive and is quite accessible to everyone.
Here is a diagram of a simple metal detector
Metal detector characteristics
- Microcircuit power supply voltage: from 3.5 to 15V
- Generator frequency: 8-10 kHz
- Current consumption: 8-12 mA in alarm mode. In search state approximately 1 mA.
- Operating temperature: -55 to +100 degrees Celsius
An old cell phone battery works well for power supply.
Coil: 140-150 turns. The diameter of the coil is 5-6 cm. Can be converted to a coil of larger diameter.
The sensitivity will depend directly on the size of the search coil.
In the scheme I use both light and sound signaling. You can choose one if you want. Buzzer with internal generator.
Thanks to this simple design, you can make a pocket metal detector or a large metal detector, depending on what you need more.
After assembly, the metal detector works immediately and does not require any adjustments, except for setting the response threshold with a variable resistor. Well, this is standard procedure for a metal detector.
So, friends, collect the things you need and, as they say, they will come in handy around the house. For example, to search for electrical wiring in a wall, even nails in a log...
Nowadays, many people try not to buy metal detectors, but to assemble them with their own hands. As a rule, it is believed that something made by hand is much worse than branded items. Practice has shown that a high-quality product can compete with metal detectors made in production.
It goes without saying that such a device may look a little worse in terms of aesthetics, but in terms of technical data, it will be competitive.
General information on metal detectors
Before you start build your own metal detector, you need to find out the principles of its operation and what types such equipment can be divided into.
Design
Metal detectors are mainly divided into five types. They differ in search depth and type of metal. They have a variety of functions that simplify the work, but still, even with such differences, some similar features can be identified.
Principle of operation
The structure of a metal detector system may seem complicated only at first glance. In fact, the whole process is simply the attraction of metal products using a magnetized coil. While the coil begins to attract metal parts, magnetic waves pass through it, and after that a signal is heard.
It is worth noting that the coils operate at low or high frequencies. If the equipment operates at low frequencies, then metal products will mainly be found only at a depth of four meters. In addition, a metal detector that operates at low frequencies can only detect large samples, while small metal parts on the surface will go undetected. A metal detector that reacts at high frequencies, on the contrary, finds only small details on the surface, but cannot work at a depth of more than two meters and search for large objects.
Type varieties
Metal detectors can be divided into 5 types, taking into account the device that is responsible for transmitting and receiving the signal.
How to make a metal detector with your own hands?
Making your own homemade metal detector is not too difficult, even if you do not have certain skills in electrical engineering and the system itself. Today there are quite a large number of metal detectors that can be assembled at home. They differ in the circuits that have to be used to create the control unit, materials and complexity of assembly.
As a rule, the most complex metal detector is assembled according to a scheme where it is necessary to install two generators into the system structure at once. This is quite difficult for a beginner. There is also a simpler type of metal detector that can be easily made at home, using only available materials.
Frame
The assembly of a homemade metal detector must begin with the development of the housing. It should be a simple barbell that can be welded or connected with fasteners. In fact, there are no defined frames for the case. Here, each person can make a barbell for themselves, but it is important to remember some factors.
First of all, the material that is selected for the manufacture of the case must be strong enough to withstand the weight of an adult for a long time. In addition, we must not forget about the size of such a bar, because if you choose the wrong length for your height, each time you search for metal objects you will have to stand in a bent state for several minutes.
Many people simplify the task of creating a body by using a simple crutch, which also has an armrest. A crutch can be easily selected to suit your height, and it is not too expensive.
Search coil
Making a homemade search coil is quite difficult, but it is possible. The first step is to start creating a device for winding the coil. First you need to take a simple board measuring 18 by 18, nails and cambric.
After this, you need to draw an even circle on the board and drive at least 16 nails along its diameter, so that they protrude slightly by about 2 cm. After this, cambrics are installed on the nails, which are tightly wrapped with copper wire. At the end of the work, the entire copper circle is firmly secured with threads, which need to be wound around the entire diameter and treated with epoxy resin.
You need to leave a 4 cm long lead, tighten the coil with electrical tape and shield it with foil. The copper wire needs to be tinned to a length of 1.25 cm and then re-wind it onto the reel. Then the action is repeated, or, more precisely, the coil is wrapped with electrical tape. You will also need to solder a contact pad to the coil terminal.
Control block
To create a control unit you will need:
All the necessary parts can be found in an old transistor type receiver. To assemble the control unit, you will need to find a suitable housing and install all the parts.
The circuit and coil are connected together using shielded wire. The cable screen is soldered to the coil terminal, insulation is installed, and the cable is fixed to the housing using electrical tape.
Conclusion
Making an entry-level metal detector is quite simple at home using available tools. All you need to do is follow the instructions and diagrams for assembling the equipment. The result is a model that can be used to search for small metal objects at a depth of up to 1 m.
