How to make a deep metal detector with your own hands. Diagram of the depth metal detector - Metal working - Designs for home and giving. How the metal detector works depending on the purpose and technical device

If you have sharply a question arose how to make a metal detector with your own hands at home, now we will find a response on it. Consider a step by step creation of three types of metal detectors with schemes, video and step-by-step photos.

Simple Metal Detector Kid FM at Home - Scheme, Installation

Baby FM is one of the simplest metal detectors today. The scheme is great for creating a pinpoint.

The kid fm works on the principle of the frequency meter (before that it was used in the mi koshi FM). Metal detector is simple, the search coil is also easy to make it yourself at home. It is for this reason that the baby FM has rarely raised the popularity of radio amateurs, despite the small flaws that we will talk about.

The new idea that arose from the creators of the Koshovy FM, had their own "pitfalls". The work of the metal detector was unstable due to the constant drift, and the search depth is relatively small. However, in the baby FM, these problems tried to eliminate the software and something from it happened.

Metal detector toddler FM scheme

Metal detector toddler FM scheme

All items are simple and available. The main thing is to use thermostable capacitors, they can be taken from the burnt multimeter or Soviet K71. But ceramic capacitors are not suitable.

Note! The better the quality of the capacitors will be, the more stable the metal detector will work!

Metal detector card Baby FM is very simple and looks like this:

To power the metal detector, the Crohn type batteries or another power source from 9 to 12 V. Metal detector itself consumes only 10 mA, and an increase in power consumption can only cause a powerful speaker. For this reason, it is better to use piezoodynamics or headphones.

Board and firmware for metal detector Kid FM can be downloaded below.

Download files:

Manufacturing Coil for Metal Detector Kid FM

The coil for metal detector Kid FM is also important as high-quality capacitors. Together with the capacitors, it forms a oscillating circuit with a frequency of 19 kHz.

Metal detector Metal detector Kid can be used as a pinpoint or beach metal detector.

Data for winding coil: The rim with a diameter of 70 mm is used by a cross section of 0.1-0.18 mm (95 turns).

In the photo below, the sample of serially produced pinpoints Kid FM:

For the beach: on the rim with a diameter of 180 mm, the Wire PET 155 0.1-0.18 (55 turns) is used.

Next, the turns are removed from the rim and are tightly wounded with a thread, then aluminum foil is wound on the coil to shield the coil, the screen is made at the end of the coil ends (the gap without foil). Then the cooled copper wire is wound onto the foil, and connect it with a minus on the board of the metal detector. To connect the coil to the metal detector board, the microphone wire (2 veins in the dormitory screen) are well suited to the ends of the coil, and the "screen to the screen".

Video, how the metal detector is working Kid FM:

How to make a metal detector with your own hands - schemes chance, detailed instructions

We present to your attention a diagram of a pulsed metal detector with discrimination of metals chance. Compared to other similar devices, it has a huge advantage associated with the relative ease of making a search coil.

Metal detector assembled with his own hands. A chance of a coil with a diameter 25 will be able to find a wedding ring at a distance of 18 cm, and the helmet - 40-45 cm. Maximum search depth is 1 meter.

Metal detector chance scheme

Metal detector chance scheme

We also give a diagram of a metal detector control buttons:

Metal detector control buttons chance

The scheme has an average level of complexity. For the assembly of the metal detector, with their own hands at home, there will be some experience.

Required components for assembling metal detector chance with their own hands

The schemes of the chance contains a microcontroller, so it will take the intra-chemical programmer for its successful assembly. Also in the scheme there is a number of fairly expensive components: screen, processor and ADC.

Upon assembly, the device is not more complicated than the Tracker PI-2 and Clone PI-W, and on the setting - it is even easier, since it does not even have a traditional trimmer for balancing OU.

Special attention should be paid to the ADC MCP3201, only after its acquisition you can move to the further assembly of the device, since it is very difficult to find it.

According to the MSR3201 scheme, but there are analogues - ADS7816, ADS7817, ADS7822, LTC1285, LTC1286, SP8528 (can differ something).

After that, the next important point is the LCD indicator, as the most expensive item, its price is about 10 dollars. Any indicators on the built-in HD44780 controller are suitable (almost all that), many firms produce them, so it is very difficult to give a specific labeling. It is best to simply select the LCD indicator with a built-in controller for two lines of 16 characters. It will be with the support of Cyrillic or not - it does not matter. It will have a backlight or not - it also does not matter if it is not planned to use in the dark or in basements / catacombs. But in any marking of the desired indicator, the "1602" will take place - denoting that this is a sign-sensing indicator with two lines of 16 characters.

If you keep such an indicator in your hands for the first time, it is better to get closer to him with it. Well, if you find a datashet on it, but you can do without it, if you carefully examine. We connect from the external source +5 to the output 2 of the indicator, and the ground - to the conclusions 1 and 5. Usually, the holes and screen of the indicator itself are sitting on the mass, and the power conductings are wider than the signal - it will also help it better and more correctly.

Conclusion 3 of the indicator through a trim resistor 22 kΩ Sadim for mass (as on the instrument diagram). Include and rotate this rapter to achieve the beautiful display of the entire top line of the indicator. It is advisable to figure out the backlight - it is removed on the opposite side of the indicator by two separate conclusions, it can be duplicated and to conclusions 15 and 16 (usually). We find where "plus", where "minus", we try to power from +5 V, preferably through a 200 ohm resistor (as in the diagram). Now, with the indicator, you are well acquainted, customized contrast and you can be confident that because of it you will not have any problems.

Now, as for the rest of the configuration, out of the OU (according to the scheme it is OP37), so far, only NE5534p has been working, which is much cheaper than said or37 and more common. Positive voltage converter with +12 V in negative -12 in can be applied without the letter S in the title. Instead of the field KP505 goes KP501A.

Detailed instructions for assembling metal detector Chance with their own hands

The process of assembling the metal detector chance should begin with the manufacture of a printed circuit board. Download Picture Figure and Other Materials for Assembling Metal Detector Chance with your own hands below.

Download files:

The collected board of the metal detector The chance looks like this:

Board Metal Detector Chance 2D

Metal detector board 3D chance

After the manufacture and spikes of the board, you need to flash the microcontroller. Last firmware version 1.2.1.

All versions of firmware for download:

For the firmware of the microcontroller, the configuration bits arrange as in the figure below:

After that, we connect the power to the metal detector, and it should earn. True while the metal he does not see. You need to make a coil.

But the already collected block looks like:

Metal detector Chance with your own hands - making coil

For winding coil, you can use the winding wire with a cross section of 0.67-0.85 mm.

After connecting the coil, you can already fully check the metal detector. But for full-fledged work with the metal detector, it is worth knocked into the housing and make a bar for him.

False responses from the metal detector there are no chance, if there are no electrical appliances included nearby. The sensitivity is good, as for selective MD. Selectivity and discrimination make your business. All nuances that accompany work even very decent and expensive corporate instruments, similarly work out here - for example, flat iron objects "beat in a collar", as the conductivity is also disappointed. It is not particularly waiting for miracles here - you will not deceive nature, but with experience on the indicator and the sound, it is possible to distinguish the glands from brass and bronze.

In the work, the chance showed itself as a simple and reliable metal detector, but everything is not very rosy with discrimination. Really, the device sends only small iron garbage and small nails, but the beer stoppers are already caused by difficulties. Also, the device, like other pulse metal detectors, does not see the gold chains.

Video with running chance on the table:

Metal detector Clone PI at home - diagram and detailed instructions

Clone PI is a pulse metal detector without determining the type of metals that can work with coils of various sizes. When using a ring with a diameter of 20 cm, the clone can find a coin at a depth of up to 25 cm, and a large metal - up to 1 meter.

The basis of the clone is taken by the Tracker PI-2 Metal Detector scheme with some changes to it.

The CLone PI metal detector has the following differences from the original (Tracker PI-2 Metal Detector):

Using the AVR microcontroller instead of a PIC controller.
Using the LCD screen without LEDs to indicate.
The presence of fast and slow auto-adjustment.
All metal detector control (without variable resistors).

CLONE PI Metal Detector Scheme

CLONE PI Metal Detector Scheme

ATTENTION: The latest firmware versions for metal detector were produced for PIC18F252 microcontroller!

Clone Pi is a pulsed metal detector of medium difficulty, it will be folded for a beginner in the manufacture. However, a person who has little experience in assembling metal detectors or other electronics, can cope with it.

The clone of metal detector contains several expensive elements: LCD screen, MCP3201 ADC and microcontroller. Before the start of making a metal detector, be sure to purchase the ADC, as difficulties may arise with its purchase!

Also, the diagram of the metal detector, contains a programmable microcontroller, so you will need a programmer with support for programming microcontrollers - PIC18F252 and use the ability to use it.

On the screen, the metal detector clone Pi displays the following information:

Response level ("fast" and "slow" sliders).
Supply voltage.
Threshold (value, inverse sensitivity).
Volume.
A sign of auto-adjustment activity (the response exceeds the threshold to any side).
A sign of a slow auto adjustment (deviation of the response to a positive side), coincides with sound alarm.
Display indicator displayed display.

In the work of the metal detector, the clone showed itself quite well. With high-quality assembly, the clone is practically no different in search characteristics from Tracker PI and other pulse metal detectors.

Assembling metal detector Clone Pi do it yourself

The clone PI metal detector assembly, as already mentioned above, you should start with the search and purchase of parts, for the manufacture of a printed circuit board. After that, you can move to the direct process of manufacturing and assembly.

First of all, you need to raise a printed circuit board:

Clone Pi Metal Detector Printing Board

After making a printed circuit board in it, it is necessary to have all radio components. Chips are better installed on the panels. Also, we connect the control buttons, the screen, speaker, and connectors for the metal detector's coil and power connectors. After the soldering is completed, you need to rinse with alcohol and dry well.

Then carefully inspect the fee to identify unapproed places and the "dullness". If everything is fine, you can proceed to programming the microcontroller.

Firmware, PCB Drawings and Other Materials that may be needed when creating a metal detector clone-pi with your own hands at home, you can download below.

Download files:

After programming, the microcontroller is installed on the fee, and you can already see the first fruits of your work.

Metal detector power is better supplied through a fuse (2-5 A). In case of closure or error when soldering, he can save your fee!

If the metal detector turned on, everything shows on the screen, it gives the sound and reacts to the control buttons, you can proceed to the manufacture of the search coil. If something does not work, then we return to the stage of visual inspection, checking the fee on the scheme and identifying the defects of the assembly!

Production of search coil for metal detector Clone Pi

A simple search coil for the CLone PI metal detector can be made from the winding enamel of the wire with a diameter of 0.6-0.8 mm, wrapped 25 turns on a mandrel with a diameter of 25-27 cm. You can use a saucepan or another suitable round item.

Then the coil's turns are tightly weaken with a tape or scotch. To the ends of the coil, we swell a retinuous stranded wire with a cross section of 0.75 mm and a length of 1-1.3 meters. For the convenience of work, protect the coil from shocks and give her aesthetic species, you can shove it into such a case:

By the end of the coil, we swell the connector and connect it to the metal detector. Include it and check the presence of a reaction to the metal. If the reaction is and you have good sensitivity, you can make an adjustment of the metal detector and proceed to the final assembly of the metal detector in the case. The photo below shows an example of the location of the elements of the metal detector inside the housing.

After assembling the metal detector and coils in the case, it remains to make a bar for it and start searching!

See also how to make it yourself

This type of construction is designed to search for coins. The process of its assembly is completely simple. However, experience in assembling such a tool is still needed. The terminator is able to detect the subject, even if the trick is minimal.

For the beginning, you should prepare the necessary equipment, namely:

multimeter, which measures speed.
LC meter.
Oscilloscope.

Next, you need to find a circuit with a breakdown on the nodes. Now you can make a printed circuit board in which the jumper, resistors, microcircuit panels and other parts should be soldered. The next step will be washing with alcohol fees. Be sure to check for the presence of defects. In the working state, the board can be checked as follows:

Turn on the power.
Unscrew the sensitivity control before the sound will not be heard in the dynamics.
Touch the sensor connector with your fingers.
When you turn on, you must blink, and then go out the LED.

If all actions have occurred, then everything is done correctly. Now you can make the coil. It is necessary to prepare a winding enamel 0.4 mm with a diameter that must be folded. On a sheet of plywood draws a circle having a diameter of 200 mm and 100 mm. Now in a circle you need to drive nails, the distance between them should be 1 cm.

Next, you can go to winding turns. For 200 mm, you should make them 30, and at 100 - 48. Then the first coil must be soaked with varnish when it dries, you can wrap it with a thread. The thread can be removed, and, by navigating the middle, it turns out a solid winding of 60 turns. After the coil, it is necessary to wrap the tape rather tightly. And from above, a foil is superimposed in the amount of 1 cm, it will be a screen, it will turn on it from above another tape. Ends should go out.

The second coil also needs to be soldered the middle. In order to start the generator, you need to connect the first coil to the board. The second coil should be wrapped with a wire in 20 turns, then connect it to the board. Now you need to connect the oscilloscope minus for minus to the board, and the plus is connected to the coil. Be sure to look at what frequency will be when you turn on and remember it or lock it on paper.

Now the coils must be put in a special shape to fill them with a resin. Next, the oscilloscope is connected to the board, minus pole, the amplitude should reach the zero value. The coils in the form are poured by a resin at about half of the depth. When everything is ready, the scales of discrimination of metals are performed.

List of parts for metal detector Terminator 3

As details for the metal detector, the trio will be needed:

In the presence of these parts, you can collect the metal detector Terminator about independently.

Metal detector scheme with metal discrimination

Metal detector with metal discrimination can be done by using a chance of a pulse appliance. The process of manufacturing the coil is quite simple.

The scheme itself can be found on the Internet. But still experience in the assembly of such devices will be odd. Metal detector assembly should be started from the board.

After the fee is made, the microcontroller will defier. And at the end of the work, we connect a metal detection device to power.

Metal detector do it yourself without chip

Homemade equipment can be made without complex chip, and using a simple transistor generator. Metal detector will be without discrimination. It will be found in the ground for 20 centimeters deep, and in dry sand - by 30 centimeters. In this device, the transmitting and receiving coils work simultaneously.

Coil for Metal Detector Terminator 3

First, you should take enamel winding having a diameter of 0.4 mm. Fold it so that there are two ends and two starts. Next it is necessary to wind from two coils at times.

Now it is necessary to make the transmitting and receiving coils, for this, two circles of 200 mm and 100 mm are drawn on the plywood sheet. According to these circles, carnations are driven, the distances between them should be 1 cm. 30 turns are wound on the enamel. Then it should be applied to the coil of varnish and lean thread, then removing from the winding, to solder the middle. So the wires are obtained one medium and extreme two.

The resulting coil should be wrapped with a tape and impose on top of a piece of foil, and on top again foil. The ends of the windings should go out.

Now it is worth moving to the receiving coil. 48 turns are already wound here. To start the generator, you need to connect the transmitting coil to the board. The average wire is connected to minus. And the receiving coil has an average output is not used. For the transmitting coil, you need a compensating on which 20 turns dangle.

The oscilloscope is connected to the board as follows: the probe with a minus on minus board, and the plus probe to the coil. Be sure to measure the frequency of coils and write it down.

After connecting coils according to the scheme, they must be placed in a special container and pour the resin. Now the oscilloscope establishes the division time (10 ms and 1 volts per cell). Now it is necessary to reduce the amplitude to the zero value. We wind up the turns until the volt value reaches zero. We make a compensating loop at the coil, which will be outside.

Shape half should shed a resin. When everything freezes, you need to connect the oscilloscope and bend the loop inside. Next twist it until the amplitude value becomes minimal. After the loop, you need to stick, check the balance, and now you can pour a resin second half of the tank. The coil is ready to work.

Repair of the coil of metal detector

Before repaid, the following tools should be prepared:

Stationery knife;
Incandescent lamp;
Capacity for glue, preferably flat;
Special or epoxy resin;
Medium and small emery;
Small spatula.

First of all, you need to dry the coil using the incandescent lamp. And with the help of a stationery knife to expand cracks on it. Glue squeeze on a flat surface and mix with a spatula. Apply this substance on the coil. In places of cracks, you can apply more resin. Now it is worth the wait until all this will thoroughly freeze. And then process the emery, using first medium, and then small. Such a procedure will help smooth out all the irregularities. Such a fairly simple way can be reanimated the oldest coil from the device for finding a metal.

Metal detector parameters depending on the purpose and technical device

Metal detectors for lovers are the simplest devices of a dynamic type. The search head of the device must constantly move, just this can appear the desired signal. If you stop the move, the signal will disappear. Such simple detectors are convenient because they do not require complex settings, make it possible to exclude medium soils. Of the shortcomings, it will be necessary to note its weak sensitivity and frequent false responses in difficult areas.

Appliance scanning speed - about 30 centimeters per second

Middle class devices have better sensitivity. In the factory configuration to such a device there are several search heads of different sizes. To configure the detector, certain skills will be required. Middle class metal detectors are able to recognize metals.

Computerized devices are an already professional tool with a liquid crystal screen and a shooter. In the memory of its processor, programs that can recognize and distinguish between the signal are loaded, classify each detected object. Professionals independently program devices under the conditions of the search, excluding unwanted responses.

Gold search tools are triggered not only on coins and jewels located in the ground, but also on native metal. It is not suitable for finding small particles, like sand. It does not recognize them, especially if the soil has high mineralization.

Otherwise, these metal detectors are very sensitive and perfectly triggered, for example, when searching for gold jewelry in the sand of the beach

Depth detectors are sharpened to search for objects located at an impressive depth. They can detect a metal at a depth of up to 6 meters, while the remaining models "break" only to 3. Such devices recognize voids and other internal indoor anomalies. The deep detectors on two coils are working, one is parallel to the surface of the soil, the other is perpendicular.

Stationary detectors are a framework installed on particularly important protected objects. They calculate any metal items in the bags and pockets of people passing through the contour.

What types of metal detectors can be done at home with their own hands

Detectors are divided into 5 basic types on the principle of detecting the desired object.

Consider which of metal detectors are suitable for making with their own hands at home:

A type	Features	Whether it is suitable for making with your own hands
Reception-transmission	Works with two induction coils. In the absence of a desired object, the signal does not pass into the receiving coil.	Yes
Induction	Combines the functions of both coils. The signal is constant, changing when determining the metal.	No, as a rule, there are difficulties with highlighting an excellent signal.
Based on the frequency meter	The design of the device includes an LC generator, changing the frequency when metal items are detected. It has low sensitivity.	Yes
With good quality meter	Has an analyzer of the LC generator signals. It does not work well at low temperatures.	Yes
Pulse	Based on the transfer of vortex pulse currents. The signal changes its character depending on the type of metal detected.	Yes

And now more about how to make a simple metal detector with your own hands on the example of the design "Pirate".

Homemade Metal Detector "Pirate": Scheme and detailed assembly description

If you just thought about how to make a self-made metal detector, do not seek to take for complex models. Start with a simple but effective "pirate". The name was invented by the author of homemade from a combination of PI (impulse) and Ra-T (radioscope). The name was taken, and a simple and understandable assembly scheme was so loved by users that Pirate became one of the most popular homemade in this area. Currently, there are already 4 modifications of the "Pirate" scheme. The metal detector is simply going to hand, without using some specific tools.

The only drawback of this device is that in the metal detection, made with its own hands, there is no scheme for working with discrimination of metals. But for the novice treasure detector is insignificant.

In addition to the details required for assembly, you will need a soldering iron, screwdriver, insulating tape

Details for assembling metal detector

For the manufacture of the device, you will need to purchase:

ceramic condenser - 1 NF;
2 film capacitor - 100 NF;
electrolyte capacitors: 10 μF (16 V) - 2 pieces, 2200 μF (16 V) - 1 piece, 1 μF (16 V) - 2 pieces, 220 μF (16 V) - 1 piece;
resistors - 7 pieces per 1; 1.6; 47; 62; 100; 120; 470 com and 6 pieces at 10, 100, 150, 220, 470, 390 ohms, 2 pieces per 2 ohms;
variable resistors - 3 pieces of 10 and 100th, 400 ohms (1W);
transistors - 3 pieces, SP557, IRF740, SP547;
2 diode 1N148;
2 chips: K157UD2 and NE555.

In addition to the listed parts, go to the headphones from the player

You still need a plastic tube for a rod, batteries or 9V batteries and a PEV wire with a diameter of 0.8 mm.

For your information! Many are interested in how to make metal detector from the phone do it yourself. Some developers even offer programs that can be downloaded to the phone and use for this purpose. Serious radio amateurs can only advise you to use some parts - for example, an entrance from headphones or a battery, perhaps a fee for creating a chip.

Metal detector schemes for manufacture with your own hands

The simplest scheme of the "pirate" looks like.

The board can be placed in the housing of the pocket receiver or any convenient in the size of the plastic box, even simple junction boxes from the arsenal of the electrician are suitable.

Important moment! To get rid of possible interference when touched to the instrument regulators, all the enclosures of the resistors are connected with a minus board.

If you want to go in your experiments on, here is a scheme for making a metal detector with a guide to gold.

Metal detector scheme "Terminator 4" with increased sensitivity

If you correctly collected a diagram, the device will work correctly. Possible problems with the microcircuit.

How to collect a metal detector's printed circuit board with your own hands

The circuit board of the metal detector is pretty simple. It can be conventionally divided into several blocks:

node of the search coil;
sound amplifier on the transistor;
impulse generator;
two-channel amplifier.

That's how it looks like.

The pulse generator is collected on the NE555 timer. Through the selection C1 and 2 and R2 and 3, frequency adjustment is performed. The pulses obtained as a result of scanning are transmitted to the T1 transistor, and it transmits the T2 transistor signal. The audio frequency gain occurs on the Transistor of the VS547 to the collector, and the headphones are connected.

For your information! You can make metal detector with your own hands without chip. On the Web you will find many analog schemes on transistor generators. Such devices will detect metal at a depth of 20 centimeters in the ground and up to 30 - in bulk sand.

How to make a coil for metal detector do it yourself

The coil is an important detail of the device. It can be made of copper wire or twisted pair. Read more in our master class.

Copper Wire Coil

Illustration	Description of action
	For the coil, a copper wire with a diameter of 0.5 mm is suitable.
	For winding, prepare such a board with guides. The distance between the guides should be equal to the diameter of the base, which you will be attached to the coil.
	Wash the wire around the perimeter of fasteners in 20-30 turns.
	Crerate the winding with a tape in several places.
	Remove the winding from the base and give it a rounded form.
	Pick up the foundation that will keep the form. It can be a lid from plastic bucket or wooden hoars for needlework.
	Connect the contour to the device and test it.
	In the collected form, the coil from the wire may look like this.
	To test the operation of the device, conduct metal objects above the coil at different heights.

A coil of twisted pair

Illustration	Description of action
	Roll the wire into two sakes, as shown in the photo, leaving two ends of about 10 centimeters each.
	Clean the winding and freeing the veins for the connection.
	Connect the veins as shown in the diagram.
	For better contact, smear the ends of the wires.
	Test the coil in the same order as the coil of copper wire.

Tip! If you want to make a more powerful coil with your own hands for the metal detector, give it an ellipse form.

Detailed instructions for setting up the metal detector "Pirate" made by hand

For the final assembly of the instrument, you will need a plastic tube. The assembly scheme is simple. The sensitivity of the detector is adjusted by potentiometers. Get the result to recognize the coin from a distance of 30 centimeters. Large size deposits, he will "hear" for meter-half. "Pirate" does not recognize non-ferrous metals under you or black, so it will have to make it easy to dig, and it is possible that you will hug on the old trough, and not to the desired treasure. But in this case, you can not take quality, but by quantity, because any metal can be passed to the recycling point.

It is possible that you are lucky, and all the works will not be in vain

What will look like a "pirate" assembly - in the next video. It should only noted that the set design for the manufacture of this device can be bought on the Internet. By the way, detailed instructions are attached, how to make the metal detector at home from the parts of the kit.

Features of deep metal detectors

The deep metal detector is attractive in that it can detect objects where other devices are powerless. A good deep metal detector made by his own hands, looks at a depth of 6 meters, and he does not interfere with roots, emptiness or other obstacles. One nuance - With it, it is possible to detect only major items, and this is understandable, because for a pair of coins you will not dig a six-meter pit.

And again we return everything to the same universal model of the "Pirate" detector. It turns out that on its basis you can make a deep device, and it is completely simple. The modification process is described in this video.

Instrument search is simply enormous popularity. Looking for adults and children, and lovers and professionals. Looking for treasures, coins, lost things and swallowed with scrap metal. And the main toilet for search is a metal detector.

There is a great many different metal detectors, on any "taste and color". But for many people, the purchase of a finished branded metal detector is simply financially counted. And someone wants to assemble the metal detector with their own hands, and someone even builds his small business on their assembly.

Homemade metal detectors

In this section of our site about self-made metal detectors, I will be collected: the best schemes of metal detectors, their descriptions, programs and other data for the manufacture of metal detector with their own hands. It does not wake up the schemes of metal detectors from the USSR and circuits on two transistors. Since such metal detectors are only suitable for a visual demonstration of metal detection principles, but not at all suitable for actual use.

All metal detectors in this section will be quite technological. They will have good search characteristics. And a competently assembled homemade metal detector will be a little shown by the factory analogues. Basically, there are various diagrams of pulsed metal detectors and metal detectors with metal discrimination.

But for the manufacture of these metal detectors, you will need not only a desire, but also certain skills and skills. Schemes of the metal detectors, we tried to split in terms of complexity.

In addition to the main data necessary for the assembly of the metal detector, information will also be information about the minimum level of knowledge and equipment for independently manufacturing metal detector.

To assemble the metal detector, you will surely need:

This list will provide the necessary tools, materials and equipment, for self-assembling of all metal detectors without exception. For many schemes, you will also need various additional equipment and materials, here only the basic for all schemes.

Soldering iron, solder, tin and other soldering supplies.
Screwdrivers, pliers, nippers and other instruments.
Materials and skills for manufacturing a printed circuit board.
Minimum experience and knowledge in electronics and electrical engineering as well.
And also straight hands - will be very useful when assembling the metal detector with their own hands.

You can find schemes for our independent assembly of the following models of metal detectors:

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.

The principle of operation of the metal detector

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.

Metal detector scheme

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. The frequency difference can be recorded in 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:

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.
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.
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.
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.
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.

Metal detector design

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:

Dust model Depth metal detector Submarine Security device Metal detector of industrial purpose

Soil. These devices are designed to search with their own hands of metal scrap, jewelry, coins, etc.
Deep. These devices are used to search for the above-mentioned metal products at great depths.
Underwater. Devices of this type are designed to operate. They can work at different depths.
Metal detectors for gold search. These devices allow you to find gold and decorations for it in any media.
Security devices. These devices are used to detect metal products on the human body and in luggage. Such devices are performed in the form of arches and installed at the entrance to the places of large clusters of people, for example, at train stations, shopping centers, etc.
Industrial. This equipment is part of the conveyor lines. Their main task is a metal detection in other substances. For example, in the sandy-ground mixture produced.
Army. The military uses such devices to detect mines, unexploded shells, bombs, etc. Military calls such devices by minist.
Devices collected by their own hands, most often they collect novice "treasures".

The use of modern materials allows you to design and make appliances with high accuracy of metal detection in different environments. The use of microelectronics made it possible to minimize their overall weight parameters. In addition, the simplicity of the electrical circuit makes it possible to make a metal detector with minimal cost with your own hands.

Main settings

As any technical device, the metal detector has certain parameters characterizing their functional properties.

Depth of detection

In the first place is the depth of metal detection. By the way, many companies producing such devices do not show the limit depth, on which their products can detect metal products. And if such a figure is indicated, then most likely this is the data obtained during laboratory tests. That is, real, field conditions differ significantly from laboratory (polygon).

This means that when performing real work with your own hands, the depth of detection will be somewhat less than indicated in the passport. Why is this happening? The fact is that the composition of the soil has a significant impact on the ability of the metal detector. In fact, one thing is to search in the river sand, and the other in the soil with a high content of iron. Metal products, especially those that are in depth for a long time, are oxidized and changed their properties and it affects the possibility of detecting an object.

Depth of detection of metal detector

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 fact 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.

Diagram of the deep metal detector

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.

Diagram of the deep metal detector

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:

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

Nominal parameters, quantities depend on the selected device concept. 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.

The process of assembling the depth metal detector

The process of assembling the deep metal detector looks approximately as follows. First collect control unit, the basis of which is a 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.

With the onset of spring, it is increasingly and more often on the banks of the rivers you can meet people with metal detectors. Most of them are engaged in "gold fishery" purely from curiosity and excitement. But some percentage really earns in search of rare things a lot of money. The secret of the success of such research is not only in experience, information and intuition, but also as the equipment they are equipped. Professional instrument is expensive, and if you own the Aza knowledge of the radio mechanic, then they probably thought more about how to make metal detector with their own hands. The editorial board will come to your aid and tell us today, how to assemble the device yourself with the help of schemes.

Read in the article:

Metal detector and its device

Such a model costs more than 32,000 rubles, and, of course, unprofessionals such a device will not afford. Therefore, we propose to study the metal detector device to collect the variation of such a device itself. So, the simplest metal detector consists of the following elements.

The principle of operation of such metal detectors is based on the transfer and reception of electromagnetic waves. The main elements of the device of this type are two coils: one - transmitting, and the second is receiving.

The metal detector works like this: the magnetic power lines of the primary field (a) of the red color pass through the metal object (b) and create a secondary field (green lines) in it. This secondary field catches the receiver, and the detector sends the audio signal to the operator. According to the principle of operation of emitters, electronic devices of this type can be divided into:

Simple, working on the principle of "reception-transmission".
Induction.
Pulse.
Generator.

The cheapest devices belong to the first type.

In the induction metal dealer, one coil that sends and receives a signal at the same time. But pulsed induction devices differ in that it generates a transmitter current, which is turned on for a while and then turns off sharply. The coil field generates pulse vortex currents in an object that is detected by analyzing the impulse attenuation entrusted in the receiver coil. This cycle is repeated continuously, can be hundreds of thousands of times per second.

How the metal detector works depending on the purpose and technical device

The principle of operation of the metal detector varies depending on the type of device. Consider the main of them:

Dynamic type devices. The simplest type of device scanning the field is constantly. The main feature of working with such a device - you need to be in motion all the time, otherwise the signal will disappear. Such devices are easy to use, however, they are weakly sensitive.
Pulse type devices.Have greater sensitivity. Often, there are additionally several coils for tuning under different types of soils and metals. Require certain skills to configure. Among the instruments of this class, electronic devices operating on a low frequency are not higher than 3 kHz.

Electronic devicesOn the one hand, they do not give a reaction (or give weak) for unwanted signals: wet sand, small pieces of metal, fraction, for example, and on the other, provide good sensitivity when searching for hidden water pipes and central heating tracks, as well as coins and other metal objects.
Depth detectors Cold for the search for objects at an impressive depth. They can detect metal items at a depth of 6 meters, while the rest of the models "break" only to 3. For example, the depth detector JEOHUNTER 3D is able to search and detect emptiness and metals, while showing the objects detected in the soil in 3- dimly.

The deep detectors on two coils are working, one is parallel to the surface of the soil, the other is perpendicular.

Stationary detectors - These are the framework established on particularly important protected objects. They calculate any metal items in the bags and pockets of people passing through the contour.

Which of the metal detectors are suitable for making with their own hands at home

To the most simplest devices that can be collected by itself include devices that work on the principle - reception-transmission. There are schemes that, by the forces, even a novice radio amateur, it is simply necessary to choose a certain set of details.

On the Internet there are many video instructions with a detailed explanation, how to make the simplest metal detector with their own hands. Here are the most popular of them:

Metal detector "Pirate".
Metal detector - butterfly.
Emitter without chip (IS).
Metal detector series "Terminator".

However, despite the fact that some clatters are trying to offer a metal detector assembly system from the phone, such structures will not be checked for a "battle". It's easier to buy a children's toy-metal detector, it will be more sense.

And now more about how to make a simple metal detector with your own hands on the example of the design "Pirate".

Homemade Metal Detector "Pirate": Scheme and detailed assembly description

Homemade on the basis of the metal detector of the Pirate series is one of the most sought-after among radio amateurs. Thanks to good working qualities of the device, it can "throw out" the subject at a depth of 200 mm (for small things) and 1500 mm (large elements).

Details for assembling metal detector

Metal detector "Pirate" is a pulse type device. For the manufacture of the device, you will need to purchase:

Materials for the manufacture of housing, rods (you can use a plastic tube), holder and so on.
Wires and isolent.
Headphones (suitable from Player).
Transistors - 3 pieces: SUP557, IRF740, SP547.
Microcircuits: K157UD2 and NE
Ceramic condenser - 1 NF.
2 film capacitor - 100 NF.
Electrolyte capacitors: 10 μF (16 V) - 2 pieces, 2200 μF (16 V) - 1 piece, 1 μF (16 V) - 2 pieces, 220 μF (16 V) - 1 piece.
Resistors - 7 pieces per 1; 1.6; 47; 62; 100; 120; 470 com and 6 pieces per 10, 100, 150, 220, 470, 390 ohms, 2 pieces on 2 ohms.
2 diode 1N148.

Metal detector schemes for manufacture with your own hands

The classic scheme of the metal detector of the Pirate series is built on the NE555 microcircuit. The operation of the device depends on the comparator, one output of which is attached to the IC pulses generator, the second to the coil, and the output to the dynamics. In the case of the detection of metal objects, the signal from the coil comes to the comparator, and after - on a speaker, which is noticing the operator about the presence of desired items.

The board can be placed in a simple junction box that can be used in the electrician store. If you are not enough such a tool, you can try to make the device more advanced plan, to help you a scheme for making a metal detector with a gold target.

How to collect metal detector without microcircuit

In this device to generate signals, transistors of the Soviet Sample KT-361 and KT-315 are used (you can use similar radio components).

How to collect a metal detector's printed circuit board with your own hands

The pulse generator is collected on the NE555 chip. Through the selection C1 and 2 and R2 and 3, frequency adjustment is performed. The pulses obtained as a result of scanning are transmitted to the T1 transistor, and it transmits the T2 transistor signal. The audio frequency gain occurs on the Transistor of the VS547 to the collector, and the headphones are connected.

To place radio components, a printed circuit is used, which can be easily made independently. To do this, use a piece of leaf geometh coated with copper electrical foil. It is transferred to it connecting parts, placing fasteners, we turn holes. Tracks cover protective varnish, and after drying, we lower the future fee in the chlorine iron for etching. This is necessary to remove unprotected sections of copper foil.

How to make a coil for metal detector do it yourself

For the base, the ring with a diameter of about 200 mm will be required (conventional wooden hoops can be used as a base), which is wound with a 0.5 mm wire. To increase the depth of the metal detection, the coil frame must be in the range of 260-270 mm, and the number of turns is 21-22 vol. If you do not have anything suitable at hand, you can wind the coil on a wooden basis.

Copper Wire Coil on Wooden Based

Illustration	Description of action
	For winding, prepare a board with guides. The distance between them is equal to the diameter of the base to which you will be attached to the coil.
	Wash the wire around the perimeter of fasteners in 20-30 turns. Crerate the winding with a tape in several places.
	Remove the winding from the base and give it a rounded form, if necessary, make an additional winding in several places.
	Connect the contour to the device and test it.

Coil from twisted pair in 5 minutes

We will need: 1 twisted pair 5 Cat 24 AVG (2.5 mm), knife, soldering iron, solder and multi-seater.

Illustration	Description of action
	Roll the wire into two pigs with a pigtail. We leave 10 cm on each side.
	Clean the winding and freeing the veins for the connection.
	Connect the veins according to the scheme.
	For better mount, smear them with a soldering iron.
	Test the coil in the same order as the copper wire device. Winding conclusions need to be soldered to a stranded wire with a diameter in the range of 0.5-0.7 mm.

Brief instructions for setting up the metal detector "Pirate" made by hand

After the main elements of metal detectors are ready, proceed to the assembly. On the metal detector rod, all nodes are found: the housing with the coil, the transmitting unit and the handle. If you did everything right, then additional manipulations with the device will not be required, as it originally has the maximum sensitivity. Thinner adjustment is performed by the variable resistor R13. The normal operation of the detector should be provided with the middle position of the regulator. If there is an oscilloscope, then it is necessary to measure the frequency to be measured on the transistor T2, which should be 120-150 Hz, and the pulse duration is 130-150 μs.

Is it possible to make your own hands underwater metal detector

The principle of assembling underwater metal detector does not differ from the usual, with the only difference that it will have to fed over the creation of an impenetrable shell using sealant, as well as over the accommodation of special light indicators that can report find from under the water. An example of how it will work in the video:

Metal detector "Terminator 3" with his own hands: Detailed assembly diagram and video instructions

Metal detector "Terminator 3" For many years, occupies an honorable place in the ranks of self-made metal detectors. The two-tone appliance works on the principle of induction balance.

Its main features are: small power consumption, discrimination of metals, non-ferrous metals mode, the mode is only gold and very good characteristics of the search depth, compared with semi-professional branded metal detectors. We offer you the most detailed description of the assembly of such a device from the people's craftsman Viktor Goncharov.

How to make a metal detector with your own hands with discrimination of metals

Discrimination of metals is the ability of the device to distinguish the detected material and carry out its classification. Discrimination is based on different metals electrical conductivity. The most simple ways to determine the types of metals were implemented in old instruments and initial level devices and had two modes - "all metals" and "color". The discrimination feature allows the operator to react to the phase shift of a certain value compared with the confined (reference) level. In this case, the device cannot distinguish between non-ferrous metals.

On how to make a homemade professional metal detector from progressive means, in this video:

Features of deep metal detectors

Metal detectors of this type can detect objects at great depths. A good metal detector made by hand, looks at a depth of 6 meters. However, in this case, the size of the find must be solid. The best detectors are best for the detection of old shells or debris sufficiently large.

There are two types of depth metal detectors: Framework and receptionist on the rod. The first type of device is able to cover a large plot of land to scan, however, in this case, efficiency, the search focus is reduced. The second version of the detector is the point, it works spoil on a small diameter. It is necessary to work with it slowly and carefully. If you put a goal - to build such a metal detector, the following video can tell you how to do it.

If you have experience in assembling such a device and its use, tell us about others!

Continuous work with maximum depth settings can help extract deeply occurring targets. In another case, customize the depth is inappropriate. Test an increase in detection depth is best in a place specially prepared for this in the field or on its own land plot.

Here 9 Soviets About how to achieve maximum productivity of the coil of the metal detector in depth.

1. Sensitivity

Sensitivity setting is the most popular way to increase the depth. Usually, when the sensitivity increases, the depth increases. But keep in mind that there is also a side effect, since too highly swinging sensitivity can reduce the likelihood of target identification, as well as bring you crazy constant chaotically published sounds.

2. Soil balance

Each modern metal detector usually has a soil balance function. Properly determine it and install - it is a direct path to increasing depth. After all, much depends on the mineralization of the soil, including at what depth you will detect goals.

3. Conduct the coil as close to the ground

Simple calculation: if you can bring the coil to the ground by 1.5 cm, then the detection depth will increase on the same 1.5 cm. Sometimes it happens enough to catch a weak signal from the coin. Sometimes the grass prevents the coil closer to the ground. In this case, take a random coil and squeezed, it is easier for her vegetation. However, take care of its additional protection.

4. Reducing discrimination

Very deeply occurring purposes are often determined by the metal detector incorrectly. But you will never spot these numerous false responses if the level of discrimination is too high, for example, as under the "Coins" programs. Reducing the discrimination to a minimum may result in success. Maybe you dug an ancient artifact, not another nail.

5. Elimination of noise

A lot of interference goes to civilized places, as well as about power lines and buried cables. Working electrical appliances are also quite strongly foundated. Usually in such cases reduce sensitivity, and this reduces the depth. Therefore, better try to work away from the interference. Also turn off your mobile phone and remove all metal objects out of your pockets. Do not wear footwear with metal elements. Do not fold the cable from the coil to the coil itself.

6. Special settings and devices

Explore the instructions for your metal detector along and across. Your device can have some unique parameters that can help you better hear and see deep goals. Some detectors are specially created in order to enhance deep, but weak signals, for example, has recently been some revival among domestic search engines about the deep firmware of the Aka Signum MFT metal detector. Or also a good result gives the use of deep nozzles. XP released such recently for Deus.

7. Big coil

Search coils of large sizes give a greater depth of detection and clearer testimony from goals. Caution! Big coil can have a lot of weight. Therefore, it would be good for the metal detector to purchase a special unloading that facilitates the wearing device. Recall that a large coil cannot be effective in highly vesting iron areas and on highly mineralized soils.

8. Experiment with posting speed

For example, quick movement with Fisher F75 gives more chances to detect deep targets than slow. Again, refer to the user manual and spend tests tirelessly - what movement speed for your metal detector gives a deeper penetrating signal.

9. Wear headphones

If you use the usual dynamic of the metal detector, you can completely naturally tritely not distinguish signals from the depth targets. In the headphones you are distracted from external noise and capture fast, weak signals. If you do not want to use headphones for any reason, then try to spend a series of air tests and remember the sounds for the most distant goals. Sometimes tiny, imperceptible changes in audio-tones are not reflected on the metal detector display.

What is the metal detector to explain to anyone. The device is dear, and some models are quite decent.

However, you can make the metal detector with your own hands at home. Moreover, you can not only save thousands of rubles on its acquisition, but also to get rich, finding a treasure. Let's talk about the appliance itself and try to figure out what in it and how.

Step-by-step instruction for assembling a simple metal detector

In this detailed instruction, we will show how you can collect the simplest metal detector from the remedies. We will need: a plain plastic box from a CD disc, portable AM \u200b\u200bor AM / FM radio, calculator, VelCro contact tape (velcro). So, proceed!

Step 1. Disassemble CD CD Box CD. Carefully disassemble the compact disc plastic box, remove the insert that holds the disk on the spot.

Step 1. Removal of plastic insert from Sidibox

Step 2. Cut 2 velcro strips. Squeeze the area in the center of the rear of your radio. Then cut 2 pieces of velcro of the same size.

Step 2.1. Memore approximately in the middle area on the back of the radio (highlighted in red)

Step 2.2. Cut 2 velcro of the corresponding size measured in step 2.1

Step 3. Secure the radio. Attach one velcro on the back of the radio and second to one of the inner sides of the CD box. Then attach the radio on the body of the plastic box of the CD "Velcro to Velcro".

Step 4. Secure the calculator. Repeat steps 2 and 3 with a calculator, but apply the velcro on the other side of the CD box. Then secure the calculator on this side of the box with the standard Velcro method.

Step 5. Setting Radio Range. Turn on the radio and make sure it is configured to AM Range. Now adjust it to the end of the AM range, but not to the radio station itself. Increase the volume. You must only hear some interference.

Prompt:

If there is a radio station, which is at the very end of the AM range, then try to get to it as close as possible. At the same time, you should hear only some interference!

Step 6. Roll the CD box. Turn on the calculator. Start turning the side of the box with the calculator towards the radio until you hear a loud beep. This beep signals us that the radio caught the electromagnetic wave from the electrical circuit of the calculator.

Step 6. We are folding the parties CD boxing to each other until the characteristic loud signal is heard.

Step 7. Apply the collected device to a metal object. Open the flaps of the plastic box again, so that the sound we heard in step 6 is barely heard. Then start moving the box with your radio and the calculator close to the metal object and you again hear a loud sound. This indicates the correct work of our simplest metal detector.

Instructions for assembling a sensitive metal detector based on a two-circuit oscillator scheme

Operating principle:

In this project, we will build a metal detector based on the dual circuit of the oscillator. One oscillator is fixed, and the other varies depending on the proximity of metal objects. The frequency of the beats between these two frequencies of oscillators is in the sound range. At the time of the detector over the metal object, you will hear a change in this frequency of the beats. Different types of metals will cause a positive or negative shift, lifting or lowering the sound frequency.

We will need materials and electrical components:

Copper multi-layer printed circuit board, one-sided 114.3 mm x 155.6 mm	1 PC.
Resistor 0.125 W.	1 PC.
Condenser, 0.1μF.	5 pieces.
Condenser, 0.01μF.	5 pieces.
Condenser, electrolytic 220μF	2 pcs.
Winding PAL type wire (26 AWG or 0.4 mm in diameter)	1 unit.
Audio connector, 1/8 ', mono, mounting on the panel, optional	1 PC.
Headphones, 1/8 'plug, mono or stereo	1 PC.
Battery, 9 in	1 PC.
Binding connector 9 in battery	1 PC.
Potentiometer, 5 com, audio taper, optional	1 PC.
Switch, single-pole switch	1 PC.
Transistor, NPN, 2N3904	6 pcs.
Wire for connecting the sensor (22 AWG or cross section - 0.3250 mm 2)	1 unit.
Speaker wired 4 '	1 PC.
Speaker, small 8 ohm	1 PC.
Locking, brass, 1/2 '	1 PC.
Threaded PVC Trumpet Connector (1/2 'Hole)	1 PC.
1/4 'Wooden Dowel	1 PC.
3/4 'Wooden Dowel	1 PC.
1/2 'wooden dowel	1 PC.
Epoxy resin.	1 PC.
1/4 'plywood	1 PC.
Carbon black	1 PC.

We will need tools:

So, proceed!

Step 1: Make a printed board. To do this, download the design of the board. Then print it and protect it on the copper board using the toner translation method on the fee. Using the toner transmission method, you print the mirror image of the board design using a conventional laser printer, and then transfer the pattern on the copper lining with the iron. At the etching stage, toner acts as a mask, keeping the copper tracks, at that time as the rest copper dissolves B. chemical bath.

Step 2: Fill the fee with transistors and electrolytic capacitors . Start with soldering 6 NPN transistors. Pay attention to the orientation of the legs of the collector, the emitter and the transistor base. Basic leg (B) is almost always in the middle. Next, add two 220μF electrolytic capacitor.

Step 2.2. Add 2 electrolytic capacitor

Step 3: Fill the board with polyester capacitors and resistors. Now you need to add 5 polyester capacitors with a capacity of 0.1μF in places shown below. Next, add 5 capacitors with a capacity of 0.01μF. These capacitors are not polarized and they can be soldered in feet feet in any direction. Next, add 6 resistors for 10 kΩ (brown, black, orange, golden).

Step 3.2. Add 5 capacitors with a capacity of 0.01μF

Step 3.3. Add 6 resistors 10 com

Step 4: We continue to fill the electrical fee elements. Now you need to add one resistor 2.2 MΩ (red, red, green, golden) and two 39 com (orange, white, orange, golden). And then hit the last resistor of 1 com (brown, black, red, gold). Next, add wiring pairs to power (red / black), output audio (green / green), reference coil (black / black) and detector-coil (yellow / yellow).

Step 4.1. Add 3 resistors (one on 2 mΩ and two to 39 com)

Step 4.2. Add 1 resistor for 1 com (extreme right)

Step 4.3. Add wires

Step 5: Wash the coil to the coil. The next step is the winding of turns on 2 coils, which are part of the LC generator lc. The first is a reference coil. I used a 0.4 mm wire in diameter for this. Cut a piece of dowel (about 13 mm in diameter and 50 mm in length).

Drill three holes in a dowel to pass through them with wiring: one longitudinally through the middle of the dubel, and two perpendicular at each end.

Slowly and carefully wore so many turns of the wire as you can around a dowel in one layer. Leave 3-4 mm naked wood every end. Hold down from the temptation to "twist" the wire is the most intuitive way of winding, but this is the wrong way. You must rotate the dowel and pull the wire. So he wrapped the wire.

Through each end of the wire through perpendicular holes in the dowel, and then one of them through the longitudinal hole. Secure the wire ribbon as soon as you finish. At the end, use sandpaper to remove the coating on two open coil ends.

Step 6: We make a reception (search) coil. It is necessary to cut the coil holder with 6-7 mm plywood. Using the same wire of 0.4 mm in diameter, wind 10 turns around the groove. My coil has a diameter of 152 mm. Using a wooden peg of 6-7 mm attach the handle to the holder. Do not use a metal bolt for this (or something similar) - otherwise the metal detector will constantly detect you a treasure. Again, using the sandpaper, remove the coating at the ends of the wire.

Step 6.1. Cut the coil holder

Step 6.2 Wash 10 turns around the groove with a wire of 0.4 mm in diameter

Step 7: Setting the reference coil. Now we need to adjust the frequency of the support coil in our chain up to 100 kHz. For this I used the oscilloscope. You can also use a multimeter with a frequency meter for these purposes. Start with connecting the coil into the chain. Next, turn on the power. Connect the shut from the oscilloscope or the multimeter to both ends of the coil and measure its frequency. It should be less than 100 kHz. You can, if necessary, shorten the coil - this will reduce its inductance and increase the frequency. Then new and new dimensions. As soon as I achieved a frequency of less than 100 kHz, my coil was 31 mm in length.

Metal detector on a transformer with W-shaped plates

The simplest metal detector scheme. We will need: a transformer with W-shaped plates, a 4.5 V battery, a resistor, a transistor, a condenser, headphones. In the transformer, leave only W-shaped plates. Mix 1000 turns of the first winding, and after the first 500 turns, make a removal of PAL-0.1 wire. Wash the second winding 200 turns with a wire PEL-0.2.

Secure the transformer at the end of the bar. Seat it from water from entering water. Turn on and close to the ground. Since the magnetic circuit is not closed, then the parameters of our scheme will change when approaching the metal, and the signals are changed in the headphones.

Easy diagram on common elements. You need to transistors of the K315B or K3102 series, resistors, capacitors, headphones, power item. Ratings are shown in the diagram.

Video: how to make a metal detector (metal detector) with your own hands

The first transistor is assembled by a setting generator with a frequency of 100 Hz, and a search generator with the same frequency is assembled. As a search coil, an old plastic bucket took a diameter of 250 mm, cut it and wrapped the copper wire with a cross section of 0.4 mm2 with a number of 50 turns. The assembled scheme was placed in a small box, sleevered and everything secured on the rod with a tape.

Scheme with two generators of the same frequency. There is no signal in standby mode. If a metal object appears in the coil field, the frequency of one of the generators changes and the sound appears in the headphones. The device is quite universal and has good sensitivity.

Easy scheme on simple elements. Chip, condensers, resistors, headphones, power supply. It is advisable to first collect the L2 coil, as shown in the photo:

On one element of the chip, the default generator with the coil L1 is collected, and the L2 coil is used in the search generator circuit. If the sensitivity zone of metallic items changes the frequency of the search circuit and the sound in headphones changes. The C6 capacitor handle can rebuild extra noises. The battery is used as a battery with voltage 9V.

In conclusion, I can say that every person familiar with the basics of electrical engineering can collect the device and possessing enough patience to bring the work started to the end.

Principle of operation

So, the metal detector is an electronic device where there is a primary sensor and a secondary device. The role of the primary sensor performs, as a rule, a coil with a wound wire. The work of the metal detector is based on the principle of changing the electromagnetic field of the sensor by any metal object.

The electromagnetic field created by the metal detector sensor causes vortex currents in such subjects. These currents cause their electromagnetic field that changes the field created by our instrument. The secondary device of the metal detector registers these signals and signals us about the finding of a metal object.

The simplest metal detectors change the sound of the alarm when the desired item is detected. More modern and expensive samples are equipped with a microprocessor and a liquid crystal display. The most advanced firms equip their models with two sensors, which allows you to search more efficiently.

Metal detectors can be consecrated to several categories:

general use devices;
middle class devices;
devices for professionals.

The first category includes the cheapest models with a minimum set of functions, but they have the price very attractive. The most popular brands in Russia: Imperial - 500A, Fisher 1212-X, Classic I SL. The instruments of this segment use the "receiver - transmitter" scheme operating on the ultra-low frequency and require constant movement of the search sensor.

The second category is more expensive aggregates, have several replaceable sensors and several handles of controls. Can work in different modes. The most common models are: Fisher 1225-X, Fisher 1235-X, Golden Saber II, Classic III SL.

Photo: General view of a typical metal detector

All other devices should be attributed to professional. They are equipped with a microprocessor, can work in dynamic and static modes. It is possible to determine the composition of the metal (subject) and the depth of its location. Settings can be automatic, and you can adjust them manually.

To build a self-made metal detector, you need to prepare several items in advance: the sensor (coil with wrapped wire), a rod holder, an electronic control unit. The sensitivity of our device depends on its quality and sizes. The rod holder is selected by the growth of man so that it is convenient to work. All structural elements are fixed on it.