Homemade treasure detector. Metal detector do-it-yourself: detailed instructions for assembling at home. How do you make your own metal detector? Easy way

The metal detector is used when searching for objects with certain electromagnetic characteristics, namely metals. IN professional activity This device is used by services conducted by inspection, archaeologists, geologists and professional treasures. In addition, the device that detects metals is often used in construction, for example, to detect fittings, wiring and profiles in the walls.

Professional equipment has a very significant drawback - highly high cost which varies depending on the depth of detection, the type of interface and metal recognition functions.

The need for the presence of the metal detector arises from ordinary people. Often these are those who decided to try themselves as a treastery. Unlike professionals, which equipment or is provided by the organization, novice lovers do not always want to acquire an expensive device. This is determined by the fact that such a purchase will not be used for professional use and is unlikely to implement themselves.

For an amateur, which only begins to work with these devices, the assembled metal detector can be approached. Homemade devices are relatively simple in the manufacture, there are many detailed instructions on the Internet. Metal detector can collect anyone in the presence of desire and required in the assembly of components; And their assembly is under the power even those who weakly understand the radiomontage. Homemade devices can have both relatively weak characteristics and not to give up by branded expensive goods. Before collecting the device, you need to know its device and varieties.

In order to understand what kind of metal detector must be assembled, it is necessary to determine the list of work carried out, as well as how exactly the purpose of the search. Externally, the instruments for the search for gold and construction work differ in constructive and technical characteristics. There are the following general search devices:

Search discrimination can occur in three options:

  • Spatial, which indicates the placement of the found object in the electromagnetic field zone, as well as its depth.
  • Geometric, showing the dimensions and shape of the object found.
  • Qualitative, defining what properties found found material.

Range of operating frequency

Metal detectors operate in a specific frequency range:

  • Expergency frequency, up to several hundred Hz. Powerful metal detectors requiring high voltage, impressive dimensions, and computer decoding of the signal makes bottom devices unsuitable for amateur use.
  • Low-frequency, up to several kHz. Enough simple schemes and construction, good noise immunity and smallness to the soil. Possess permeability depending on the separated voltage, up to 5 meters. The sharper is reacting to ferrous metals and reinforced concrete structures.
  • Increased frequency, up to tens of kHz. They have more complex schemes, but less demanding towards coils. Relative noise immunity and depth of detection up to one and a half meters. Very bad work in wet and mineral soils.
  • Radio frequency applied to search for non-ferrous metals, such as gold. The depth of detection is less than a meter in dry soils, very critical to the design and quality of used coils.

Search Classification

There are many search methods, but many of them apply only in professional activities, and unrealizable in homemade devices. To more applicable at home can be attributed:

  • Without receiver (parametric).
  • On beats.
  • Phase accumulation.
  • Receiving-transmitting.

Parametric metal detector

In these devices, there is no receiving coil and receiver, and the object detection occurs due to its effect on the generator coil, the change in its parameters, such as the frequency and amplitude of the fluctuations produced, is fixed by different possible methods. Simply simple in the assembly and have relatively high noise immunity. More often used as magnetioctors due to weak sensitivity.

Receiving-transmission device

The device consists of transmitting and receiving coils, the EM transmitter of oscillations, and can also be equipped with a discriminator, which will detect only certain metals.

The coil creates an electromagnetic field; If materials with an excellent electromagnetic field are in its zone, the receiver catches them, and gives sound signal On detection. If an object does not have electrically conductive properties, but having ferromagnetic characteristics, then it will distort the electromagnetic field by shielding.

These devices are achieved better performance In its working frequency range, but their independent production requires a high-quality system of coils, which must be perfectly located relative to each other.

The receiving-transmitting metal detector with one coil is called inductive. Its creation is easier due to the fact that you do not need to pick up coils, but it is required to divide the secondary weak signal relatively emitted primary.

Phase sensitive instrument

These metal detectors are represented by impulse with one coil or devices with two coils, each of which is affected by a separate generator.

In the case of a pulsed phase sensitive metal detector, the radiated pulses during a collision with the desired metal are delayed, and during the increasing phase shift, the discriminator is triggered and the signal. The closer the device to the object, the more often the signals become. In this principle, the popular homemade metal detector "Pirate" with discrimination of metals is working.

The principle of operation of the device with two coils is based on the fact that the electromagnetic fields of two coils are synchronized and operate in the tact; And when the field is distorted, there is a distance, and the discriminator begins to make signals. This type of device is easier to make than one coil, but the depth of possible detection is reduced.

On the principle of harmonics

IN this device Constructively there are two coils: Working and reference. The reference oscillatory coil is small, protected from extraneous vendor, or stabilized by a resonator. The frequency of the working search coil depends on the presence of desired items in the radiation zone.

Before starting the search, they are configured to match the frequencies and, as a result, a monophonic sound. Changing the tonality means entering metal items into the electromagnetic field zone, and on the level of change determine the size and depth of the item.

Coils metal detector

The main requirement for the quality of homemade devices is competent manufacture of coil and its reliable shielding.

When creating an instrument, the diagram of the device is customized to the coil before obtaining optimal values. With incorrectly selected coil metal detector, if it works, then with very bad characteristics. In this regard, when choosing an option for manufacture, you need to carefully look at the description of the coil. If it is not fully complete, it is better to make another device.

The coil size is also important. The soil is widely nicknamed, but in case of detection of large items, their signal will score potentially necessary minor items. Also, to increase the depth of detection, you need to have a wider coil.

It is generally accepted to use coils with a diameter of up to 90 mm when searching for profiles and reinforcement, up to 150 mm on the smallest, and diameters up to 600 mm for searching for bulk iron.

It will be ideal if the metal detector is designed to work with the coils of different dimensions.

Noise immunity

Coils are well caught of various types Putting, I. there are 2 common ways to increase noise immunity:

Baskets

These coils are represented by flat and bulk options, they are stable, less sensitive to the tips, have high discrimination. For a beginner easier to wind the flat coil.

Computer disks, plates and saucers can act as its mandrel, and you can calculate the winding yourself. Volumetric option to wind without calculating using computer programs It is impossible.

Simple metal detector do it yourself

This version of the self-made metal detector consists of an decoder of signals, alarm device and coil. For its assembly, you will need:

  • Chip PIC12F675 or its analogues and programmer for firmware.
  • Resonator for 20 MHz.
  • Voltage stabilizer AMS1117.
  • Capacitors for 15 PF and 100 NF ceramic, electrolytic per 10 μF and film per 100 nf.
  • Resistors 470 Ohm, 10 com.
  • Sound emitter.

Soldering is made by mounted or inserting method, the voltage is required to power the scheme. Stabilizer controls the output 3.3 V.

The coil is wound on a mandrel 10 cm with a wire with a sequence of 0.3 mm. It is required to close 90 turns tightly, and the resulting design is tightly wrapped with scotch and put in the Faraday screen.

It turns out a fairly powerful metal detector for deep search, which can be set discrimination: when the black and non-ferrous metals are detected, the sound of different frequency will be published.

Professional metal detectors are often pretty expensive and do not afford to lovers. On the Internet there are metal detector schemes, some of them can be collected with their own hands without having special skills of radio editing and professional equipment. If desired, you can collect even the underwater metal detector, which will equally work both on land and in water.

In order for the independently assembled device perfectly performed all possible requirements, it is necessary to understand the design of the metal detector, to determine the type of search work, which will be conducted with the device after its assembly. This will help to choose exactly the version of the execution of the metal detector, which is necessary for a novice treasure detector.

Devices capable of detecting metal objects in weakly conducting media are called metal detectors, or metal detectors. They can be used to search for black and non-ferrous metals. The homemade metal detector for coins is able to detect a trifle at a distance of 10 to 50 cm, and more volumetric metals from 0.5 to 3 m.

The use of metal detectors is known since ancient times, and large growth of their production falls at the end of the 60s. Thanks to the progress and multiple schemes, any novice radio amateur can make a metal detector with their own hands without resorting to extensive knowledge in electronics. The main advantage of self-made metal detectors is small costs.

We collect the simplest metal detector working on two frequency generators - a metal detector on beats. At the same frequency, the generators are synchronized, but when the metal coils in one of the metal coils occurs, the frequency changes in one of the generators. As a result, the circuit reproduces the sound of the frequency differences of two generators.

Tools and materials for the device

To make a self-made metal detector, you need to divide the process into three stages - the creation of the structure, the implementation of the scheme, the assembly into one. We describe the approximate list of tools and materials that may be needed for these purposes. Further, the article will explain in more detail: from which you can collect a metal detector for gold, and which material it is better to use. Let's start with the preparation of the tool for novice diggers. For work you will need:

  1. Nippers for working with wires and details;
  2. Knife;
  3. Saw for plastic. In the extreme case, you can use a knife or a regular saw;
  4. Soldering iron;
  5. Screwdriver Set.

Necessary materials:

  1. Insulating tape;
  2. Set for soldering. You can use just rosin and solder;
  3. Glue;
  4. Details and fees for the scheme;
  5. Coil wire;
  6. A piece of plastic and plastic tube;
  7. Fasteners.

Preparation of details

Here is described detailed instructions About choosing and search for details.

Initially, it is necessary to determine the material and fastening of the components of the metal detector and find the necessary components.

As a bar, you can use crutch with armrest, fishing rod, stitched polyethylene or polyvinyl chloride tube (Fig. 2).

Coils and scheme will be located downstairs on a stand attached to the rod. So it is important to take into account the rod robes and its material. Preference is better to give dielectrics, i.e. Not conducted electricity - Plastic, tree and more. It is necessary to make a handle so that it is comfortable to keep the metal detector made. In the case of a crutch, it is not needed, but in another case you can attach both the steering wheel from the bike and the other self-made design.

Stand for the scheme and coils can be made from conventional plastic. It is easy to cut, and he weighs little. One bottom sheet is needed, since to adjust the device you need access to coils. To reduce the vibration of the scheme with coils, it is desirable to choose plastic beast.

After the preparation of the rod and the stand need to be connected. You can use fasteners, but do not forget that for proper work Schemes should not be brought to metal products closer than 30 cm. Therefore, we use good glue, for example, liquid nails. You can use other materials - it all depends on your abilities in plumbing and carpentry work.

Wire for coils should be isolated. An enameled copper wire with a diameter of 0.5 - 0.7 mm of the PEV or PAL brand is suitable. Wire length is about 100 meters. Lacquer for fixing parts is suitable oil.

Installation of parts can be carried out by attachment on textolite or on cardboard. For novice radio amateurs in specialized stores, you can buy a treated textolite from a plant or material with holes for parts. You can also make a fee from solid raw textolite. To do this, you need to mark the placement of contacts of radio components in the diagram, then divide the sections of the textolite to the knife and return the sites and tracks (Fig. 3). Excessive part of the textolite cut the saw for plastic.

To assemble the working metal detector of radio components, you can find houses in the old radio equipment, but it is advisable to purchase in the store. The same details must be completely identical and preferably from one batch. Table 1 shows the list of necessary parts and comments, the execution of which will lead you to the assembly of a high-quality metal detector.

After finding all the necessary details, you can easily assemble the metal detector at home.

Build device

Having considered the list of necessary materials and parts, they will reply in detail how to assemble the metal detector with their own hands.

For winding coils, we use any round item with a diameter of 20 - 25 cm. The number of turns is equal to 30. We derive one end of the wire and wind up 10 turns, after which, without breaking, we derive the second end. We continue the winding of another 20 turns and derive the third end. The wire conclusions are made with a reserve from 10 to 20 cm. Remove the resulting winding from the subject and tightly wrapped with a tape, leaving three output of the wire (Fig. 5).

We carry out the second coil in the same way. For the greatest success, we perform the coils as much as possible, with a mirror reflection.

We proceed to assembling radio components. Expose parts on the board and carry out a soldering according to the scheme in Figure 4. When using cardboard or material with holes, the connection of parts manufacture with insulated wires with any cross section. When using the prepared textolite, perform a soldering to finished tracks. The scheme can be placed in a wooden or plastic box.

We solder the conclusions of the coils, according to the scheme. We solder and display two wires with a battery connector.

Prepare a stand for the scheme and coils. We select dimensions with regard to the fact that the distance between the coils must be at least 10 cm, since between them should, respectively, contain a diagram and attached rod.

To correctly fasten the coils, temporarily throw the headphones to the diagram and insert the battery. Small movements of the coils we achieve silence in headphones with single clicks or as high as possible, barely audible sound. We try to bring metal to one of the coils, if you hear significant changes, this indicates the performance of the metal detector. Fix in that position the coil and fee. If possible, it is better to glue it right away, and then smeared with oil varnish.

For headphones, we do two holes in the rod - from below. With the help of bruises, the tape and the soldering iron are increasing the headphic wire to the required length - from the scheme to the region of the ears of the person. Immediately need to take into account growth. We stretch the wire inside the rod and solder to the diagram.

Cut the surplus of the stand and attach a rod to it convenient for you.

Adjustment

The most accurate setting is the absence of click headphones, and the presence of a barely audible high-frequency patch.

Adjustment in three ways:

  1. Drive metal alternately to coils. On that coil, where the noise ceased, remove the last coil inside the rings of the coil.
  2. You can use small pieces of aluminum. We bring them to the coils and we achieve silence or single clicks. Fix glue.
  3. I fix the tube on the coil and wake a ferrite rod through it. Having achieved the desired result, fix the rod in this position. Check out the video below, which demonstrates how to make a homemade knob to configure this method.

With good hearing and experience, you can use the manufactured metal detector as a simple metal detector with discrimination, that is, with recognition of metal types.

Modernization

If you figured out how to make the easiest metal detector with your own hands, you can proceed to a small upgrade without chip in Figure 9. The list of parts is assembled in Table 2.

The new scheme has a RC contour consisting of a resistor and capacitor. It will achieve increased sensitivity.

Added variable resistors to adjust the scheme, not a touch of coil. This will allow to seal the sensing unit of the metal detector in a solid box that protects against shocks.

Instead of headphones, you can use a speaker with a condenser for a small increase in volume.

In this scheme, the coil is placed one on one, as shown in Figure 10. Before fixing the coils we adjust them with moving.

When you turn on, exhibit variable resistors to the same position and rotation we achieve the exact setting. After that, it remains only to take a metal detector and go to search for nuggets or metals. Tested in practice - if you search on any Russian beach, you can find gold and silver.


Metal detector is electronic device To search and distinguishing metals, metal items that can be hidden at different depths under the layer of sand, earth, in the walls of the premises and various designs.

The concepts of metal detectors performed on transistors, chips and microcontrollers are presented. Metal detector of factory production is enough expensive deviceTherefore, the independent manufacture of a self-made metal detector can save no little tools.

The schemes of modern metal detectors can be built according to various principles of work, we list the most popular of them:

  • Method of beagi (measurement of changes in the reference frequency);
  • Induction balance at low frequencies;
  • Induction balance on disputed coils;
  • Pulse method.

Many novice radio amateurs and treasure detectors are asked: how to make a metal detector? It is desirable to start your acquaintance from the assembly of a simple metal detector scheme, it will help to understand work. similar device, Get the first skills in the search for treasures and products from multicolored metals.

Now there is a fairly large selection of multimeters, at a very different price. Now the radio amateur may not be limited to a modest set of functions of the legendary M-838. We can get more expensive to purchase a more modern device, which is capable of measuring the frequency of alternating current.

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Metal detector is designed to detect a metal object (well cover, cutting pipe, hidden wiring). Metal detector consists of parallel stabilizer Voltages (transistors V1 v2) in the generator high (about 100 kHz) frequency on the transistor V4, the detector of RF oscillations (V5) and ...

13 5435 6

Metal detector allows you to detect any metal object at a distance of up to 20 cm. The detection range depends only on the area of \u200b\u200bthe metal subject. For those who are not enough for this distance, such as folders of treasures, it is possible to recommend to increase the size of the frame. This should increase the depth of detection. The concept of metal detector is shown in the figure. The scheme is collected on transistors operating in ...

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The scheme of the self-made metal detector on the beats, which is built on five chips. Finding a 2.25mm coin at a depth of 5 cm, a gun - at a depth of 10 cm, a metal helmet - 20cm. The concept of metal detector on the beats is shown below. The scheme consists of the following nodes: Quartz generator, measuring generator, synchronous detector, Schmidt trigger, Indication device ...

11 5122 4

The diagram presented in the picture is a classic metal detector. The operation of the scheme is based on the principle of super-neurodine frequency conversion, which is commonly used in a super-enerodine receiver. The concept of a metal detector with an integral UNG, it uses two radio frequency generators, whose frequencies are 5.5 MHz. The first radio frequency generator is assembled on the T1 transistor type BF494, frequency ...

5 5118 2

This metal detector, despite the small number of details and simplicity in the manufacture, is quite large sensitivity. Large metal objects, such as the heating battery, it is able to detect up to 60 cm at a distance, small, for example, a coin with a diameter of 25 mm - at a distance of 15 cm. The principle of operation of the device is based on the frequency change in the measuring generator under the influence of a number of metals and. ..

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A simple compact metal detector is needed to detect in the walls under the layer of plaster various metal objects (for example, pipes, wiring, nails, fittings). This device is completely autonomously, it is powered by a 9-volt battery of the Krone type, consuming 4-5 mA from it. Metal detector has sufficient sensitivity to detect: pipes at a distance of 10-15 cm; Wiring and nails at a distance of 5-10 ...

8 4915 0

Scheme of a small-sized high-economy metal detector with good repeatability and high performance, using widespread and inexpensive parts. Analysis of most common schemes showed that all of them feed on a voltage source not lower than 9 V (i.e. "Krona"), and this is expensive and uneconomical. So, assembled on the K561LE5 microcircuit ...

18 5688 1

The device allows you to find metal objects located in a neutral medium, for example, soil, due to their conductivity are called a metal detector (metal detector). This device allows you to find metal items in various environments, including in the human body.

In many ways, thanks to the development of microelectronics, metal detectors that produce many enterprises throughout the world have high reliability and small overall-weight characteristics.

Not so long ago, such devices could most often see from sappers, now they enjoy rescuers, treasures, communal service workers when searching for pipes, cables, etc. Moreover, many "treasures" use metal detectors that they collect do it yourself .

Design and principle of device operation

Metal detectors offered on the market work on different principles. Many believe that they use the principle of impulse echo or radar. Their difference from locators is the transmitted and received signals, act constantly and at the same time, to all of the time they work on the coinciding frequencies.

Instruments operating on the principle "Reception" are recorded reflected (re-infused) from the metal object. This signal appears due to the impact on the metal object by an alternating magnetic field, which generates metal dealer coils. That is, in the design of the devices of this type, there are two coils, the first - transmitting, the second - reception.

The instruments of this class have the following advantages:

  • simplicity of design;
  • great features for detecting metal materials.

At the same time, the metal detectors of this class have certain disadvantages:

  • metal detectors may be sensitive to the composition of the soil, in which the search for metal objects produce.
  • technological difficulties in the production of the product.

In other words, the devices of this type must be customized with your own hands.

Other devices are sometimes called metal detector on beats. This name came from the distant past, more precisely since the times when super-metrogenous receivers were widely exploited. Bilation is a phenomenon that becomes noticeable when summarizing two signals with close frequencies and equal amplitudes. The beating consists in pulsing the amplitude of the amplitude signal.

The signal pulsation frequency is equal to the frequency difference difference. Skipping such a signal through the rectifier, it is also called the detector, allocate, the so-called difference frequency.

Such a scheme was used for a long time, but these days, it does not apply. They were changed synchronous detectors, but the term remained in use.

The metal detector on the beyon works using the following principle - it registers the frequency difference from two generator coils. One frequency is stable, the second contains an inductor inductor.

The device is set up with your own hands so that the generated frequencies coincide or at least were close. Once, a metal falls into the action zone, a change in the specified parameters and the frequency changes. Frequency difference can be registered different ways, ranging from headphones and ending with digital methods.

The devices of this class are characterized by a simple sensor design, weak sensitivity to the mineral composition of the soil.

But besides this, when they are operating, it is necessary to take into account the fact that they have high power consumption.

Typical design

The composition of the metal detector includes the following components:

  1. The coil is a box-type design, it has a receiver and a signal transmitter. Most often, the coil has an elliptical form and polymers are used for its manufacture. It contains a wire connecting it with a control unit. This wire transmits a signal from the receiver to the control unit. The transmitter generates a signal when the metal is detected, which is broadcast to the receiver. The coil is installed on the bottom bar.
  2. The metal part on which the coil is fixed and its tilt angle is configured, called the bottom rod. Thanks to this solution, a more careful study of the surface occurs. There are models in which the lower part can adjust the height of the metal detector and provides a telescopic connection with a barbell called average.
  3. The middle rod is a node located between the bottom and the upper rods. It fixes fixtures that allow you to adjust the device dimensions. On the market you can meet models that consist of two rods.
  4. The upper rod, as a rule, has a curved view. It resembles the letter S. This form is considered optimal to fasten it on hand. It is installed on it, a control unit and handle. The armrest and the handle are made of polymeric materials.
  5. The metal detector control unit is necessary for the processing of the data resulting from the coil. After the signal is transformed, it is sent to headphones or other means of indication. In addition, the control unit is designed to adjust the device mode. The wire from the coil is joined by a quick-release device.

All devices included in the metal detector are performed in moisture-proof.

This is such a relative simplicity design and allows you to make metal detectors with your own hands.

Varieties of metal detectors

The market presents a broad nomenclature of metal detectors used in many spheres. Below is a list in which some varieties of these devices are indicated:

Most of the modern metal detectors can find metal objects at a depth of up to 2.5 m, special depth products can detect a product at a depth of 6 meters.

Frequency of work

The second parameter is the frequency of work. The thing is that low frequencies Allow the metal detector to see at a rather large depth, but they are not able to see small details. High frequencies allow you to notice small objects, but does not allow soil browsing to a large depth.

The simplest (budget) models operate at one frequency, models that refer to the average price level are used in 2 or more frequencies. There are models that, when searching, use 28 frequencies.

Modern metal detectors are equipped with such a function as metal discrimination. It allows you to distinguish the type of material on depth. At the same time, when the ferrous metal is detected in the search headphones, one sound will sound, and when the color is discovered.

Such devices refer to Ipulso - balanced. They use frequency from 8 to 15 kHz in their work. As a source, batteries are used in 9 - 12 V.

The devices of this class are able to detect a golden subject at a depth of several tens of centimeters, and products from ferrous metals at a depth of about 1 or more meters.

But, of course, these parameters depend on the device model.

How to assemble a homemade metal detector do it yourself

In the market there are many models of instruments for finding a metal in the ground, walls, etc. despite its external complexity, make metal detector with their own hands not so and difficult and can almost anyone can make it. As already noted above, any metal detector consists of the following key components - coils, decoder and a signaling device signaling device.

To assemble with your own hands, such a metal detector requires the following set of elements:

  • controller;
  • resonator;
  • condensers of different types, including film;
  • resistors;
  • sound emitter;
  • voltage regulator.

Metal detector simplest

The diagram of the metal detector is not distinguished by complexity, and it is possible to find it or on the expanses of the global network, or in specialized literature. The above is a list of radio elements that will be useful for assembling the metal detector with their own hands at home. A simple metal detector can be collected with their own hands using a soldering iron or another. affordable way. The main thing at the same time, the details should not touch the device's housing. In order to ensure the work of the assembled metal detector, power supplies of 9 - 12 volts are used.

For winding the coil, a wire with a cross-section diameter is used within 0.3 mm, of course, it will depend on the selected scheme. By the way, the wound coil must be protected from the impact of extraneous radiation. To do this, it is shielded with your own hands with the help of an ordinary food foil.

For the firmware of the controller apply special programswhich can also be found on the Internet.

Metal detector without microcircuits

If a novice "treasure detector" does not have a desire to bind to chips, there are schemes without them.

There are simpler schemes based on the use of traditional transistors. Such a device can find a metal at a depth of several tens of centimeters.

Depth metal detectors are used to search for metals at large depths. But it is worth noting that they are not suiced and therefore it is quite possible to gather it with their own hands. But before proceeding to its manufacture, it is necessary to understand how a typical scheme works.

The diagram of the deep metal detector is not the simplest and there are several options for its execution. Before assembling it is necessary to prepare the following set of details and elements:

  • condencators of different types - film, ceramic, etc.;
  • resistors of different nominal numbers;
  • semiconductors - transistors and diodes.

Nominal parameters, quantity depend on the selected concept instrument. To assemble the above elements, you will need a soldering iron, a set of tool (screwdriver, pliers, nippers), material for the manufacture of the board.

Assembly process deep metal detector Looks like approximately in the following way. First collect control unit, the basis of which is printed circuit board. It is made of textolite. The assembly scheme is then transferred directly to the surface of the finished board. After the drawing is transferred, the board must be emitted. For this purpose, a solution is used, which includes hydrogen peroxide, salt, electrolyte.

After the board is met, it needs to perform holes for installing the circuit components. After the logging of the board is performed. The most important stage occurs. Installation and soldering with your own hands on the prepared fee.

For winding the coil with their own hands, the wire of the PEV brand with a diameter of 0.5 mm is used. The number of turns and the diameter of the coil depends on the selected depth metal detector scheme.

A little about smartphones

There is an opinion that it is quite possible to make a metal detector from a smartphone. This is not true! Yes, there are applications that are installed under the Android OS.

But in fact, after installing such an application, it will really be able to find metal objects, but only pre-magnetized. Search and even more so discriminating metals he will not be able.


To collect such an apparatus for everyone, even those who are completely far from electronics, just need to solder all the details as in the scheme. The metal detector consists of two microcircuits. They do not require any firmware and programming.

12 volt food, you can from finger batteries but better Akb on 12V (small)

The coil is wound on the mandrel 190mm and contains 25 turns of the wire PEV 0.5

Characteristics:
- Current consumption 30-40 mA
- reacts to all metals of discrimination no
- Sensitivity 25 mm Milometer coin - 20 cm
- large metal objects - 150 cm
- All parts are not expensive and easily accessible.

List of necessary parts:
1) soldering iron
2) Textolite
3) Wires
4) Drill 1mm

Here is the list of necessary parts


The diagram of the metal detector itself

The diagram uses 2 chips (NE555 and K157UD2). They are common enough. K157ud2 - you can choose from the old equipment that I successfully did







Capacitors of 100nf must be taken film, these, the voltage take as little as possible


Print the sketch of the board on plain paper


Cut on its size a piece of textolite.


Tightly apply and sharp item to the places of future holes


That's how it should happen.


Next, we take any drill or drilling machine and drilling holes




After drilling, you need to read the tracks. You can do it through, or simply draw them nitro varnish with a simple tassel. The tracks should work out exactly the same as on a paper template. And polevim fee.


In labeled red places, put the jumpers:



Next, just solder all the components into place.

For k157ud2 it is better to put a transition panel.






For the search coil winding, you need a copper wire with a diameter of 0.5-0.7mm


If there is no one, you can use others. I have not enough copper lacquered wire. He took an old network cable.


Removed the shell. There were enough wires. I had enough two lived, they also wind the coil.




According to the coil diagram with a diameter of 19 cm and contains 25 turns. I immediately note that the coil needs to do this diameter on the basis of what you will search. The more the coil is the deeper the search, but the big coil sees the little details badly. Little coil sees fine details well, but the depth is not big. I immediately wound my three coils 23cm (25 turns), 15 cm (17 turns) and 10 cm (13-15 turns). If you need to accumulate scrap metal, then we put more, if you search for small things on the beach, then the coil is smaller, well, they will figure it out.

The coil is winding on something like a suitable diameter and tightly wind the tape, so that the turns were tightly near each other.




The coil should be as smooth. The speaker took the first one.

Now we all connect and try the scheme for performance.

After power supply, you need to wait 15-20 seconds while the diagram warms up. We put the coil away from any metal, best to hang in the air. After starting to twist the variable resistor 100k until clicks appear. As soon as the clicks appeared twist reverse sideAs only clicks are enough. After that, we also set up a 10K resistor.

At the account of the chip K157UD2. In addition to the one that I have flocked, I also asked for a neighbor and two bought on the radio market. Inserted the purchased chips, turned on the device, and he refused to work. For a long time I broke my head until I just did not put another chip (the one dropped). And everything immediately earned. So that's why the transition panel is needed to choose a living chip and do not suffer with feeding and depressing.

Purchased microcircuits