Metal detector Clone PI W- this is a slightly simplified and cheaper version of the Clone PI-AVR impulse metal detector. In the Clone PI-W MD, the LCD screen is replaced by 10 LEDs, and the control is carried out by six tact buttons. This metal detector is perfect for building an underwater and deep search device.
Technical characteristics of the metal detector Clone Pi V:
- Indication: LED; sound multitone;
- Search mode is static;
- Discrimination: none
- Supply voltage: 12 V
The maximum depth of detection of objects with a ring sensor is 19 centimeters:
- Coin with a diameter of 25mm - up to 30cm;
- Helmet - up to 60cm;
- Maximum depth - up to 150cm;
- Coin with a diameter of 25mm - up to 30cm;
- Helmet - up to 60cm;
- Maximum depth - up to 150cm;
With deep loop sensor 1.2x1.2m
- Helmet - up to 140cm;
- Steel barrel 200l - up to 200cm;
- The maximum depth is up to 300cm.
- Steel barrel 200l - up to 200cm;
- The maximum depth is up to 300cm.
The main advantage of this device is its relatively low cost, ease of setup and use. If the board has been soldered properly, the device starts working almost immediately, the only setting is to adjust the variable resistor. ).
As an example, we will consider the most affordable version of the circuit - the Clone PI-W metal detector based on the CD4066 chip.
and Clone Pi V can be bought in our online store MD KIT
AndClone Pi V can be bought in our online store MD KIT
Parts list for Clone Pi V
Firmware for the metal detector controller Clone Pi V
To flash the Mega8 controller, you need a programmer, I advise you to use the AVR ISP programmer, it has a low cost and is quite suitable for our tasks, we will flash the controller using the AVRDude program. The most stable firmware for Clone Pi-V is version 1.2.2m
Configuration bits must be set as in the picture, note that they are inverse (PonyProg)
Making a coil for Clone PI V
The coil is made of PETV wire with a cross section of 0.4-0.5 mm for a conventional sensor and 0.66-0.8 mm for a deep frame. It is advisable to take the wire for connecting the coil and the metal detector unit with good flexible insulation and one pair of cores, with a cross section of 0.75 mm². The coil does not need to be shielded. We connect the leads of the coil and the wire by soldering, and reliably isolate them. Solder the connector on the end of the wire.
How to make a twisted pair Clone metal detector coil in detail
Setting up the Clone PI W metal detector
The Clone PI W metal detector practically does not need to be configured, all its configuration comes down to the following steps: We turn on the device away from metal objects and switched on electrical devices, and wait until the entire LED scale has passed. Then we bring a control metal object such as a coin and check the sensitivity of the metal detector. Then we tighten the tuning resistor, reboot the metal detector and check the sensitivity again. Repeat the manipulation until we achieve the best result.
After setting up, in the metal detector, you can also use the control buttons to adjust the volume and sensitivity of the metal detector. The higher the Barrier (adjustment range 0 – 10), the lower the sensitivity. We lower the threshold until false alarms appear, with the metal detector coil raised into the air. For a normally assembled and tuned metal detector, the normal threshold is 3-5.
(high quality workmanship)
Clone PI AVR- modern impulse microcontroller metal detector with LCD screen and sound indication. The principle of operation is based on the excitation of pulsed eddy currents in a metal object and the measurement of the secondary electromagnetic field that these currents induce.
Able to work with coils of different diameters (coils up to 120 - 150 cm in diameter) automatically adjusting to work with them. The metal detector can be effectively used to search for any metal objects, up to 4 meters in depth, based on the installed coil. It has good sensitivity to small objects.
The Clone PI AVR metal detector has a display backlight for night time operation. There is a detuning from the ground (depending on humidity and the content of metallic impurities). In the settings of the device there is also an indication of the battery power (when the set level is reached, the metal detector automatically turns off, which is important when working on battery power). There is a barrier, a sensitivity threshold at which the metal detector is triggered by a metal object.
Thanks to the microcontroller (processor) used in the clone pi avr metal detector circuit, the device is fully automatic, has an intuitive menu that even any beginner will master it very quickly. A worthy competitor to industrial metal detectors, but the cost is much cheaper. The disadvantage of the metal detector is the lack of selectivity (does not distinguish between ferrous and non-ferrous metals)
Clone PI AVR is a somewhat simplified version of the Clone PI pulse metal detector. In turn, Clone PI is a slightly revised version of the Tracker PI pulse metal detector - the commercial version - Koschey PI. Therefore the name Clone.
| Characteristics of the impulse microprocessor-based metal detector Clone PI AVR | |
| Principle of operation | PI (Pulse) |
| Selectivity of metals | No |
| Nutrition | Two lithium 3.7V 2200mA |
| Instrument weight | 1300 grams |
| Height | 105 cm |
| Control | Push-button (4 kn.) |
| Menu settings | Ground balance, volume control, display backlight control, search sensor “guard interval” control, setting the device to automatically turn off when the battery is low |
| Display | LCD indicator 2 lines 16 characters |
| Voice acting | Adjustable (speaker) |
| Firmware | V 1.8.1 with Russian translation (or English) |
| Purpose of use | 5-point evaluation of the device | Notes |
| Search for coins, rings and other valuable items made of gold and other non-ferrous metals | 4 | Does not distinguish between metals, but has very good sensitivity to small objects (coins, rings, chains) |
| Search for objects of military archeology (walking in the war), non-ferrous and ferrous metals | 5 | Fits perfectly, finds a soldier's helmet (coil 24 cm in diameter) at a depth of 55 cm, larger objects up to 140 cm |
| Search for non-ferrous and ferrous metals of large sizes, collection of scrap metal | 5 | Fits perfectly, able to find metals at great depths |
| If desired, and with the appropriate knowledge of electronics, the device can be made independently! The author of the device is Andrey Fedorov, he is Andy_F. Author's homepage: |
- this is a somewhat simplified version of the metal detector, it has a liquid crystal screen, replaced by LEDs. Also, the controls were cut in the metal detectors and only the most necessary functions were left. Initially, the metal detector was designed as an underwater version of the Clone, but it has become very popular on the ground as well.
Below in the article, you will find all the necessary materials, to assemble the Clone PI W metal detector with your own hands In the meantime, let's talk a little about the device itself.
The main advantage of "Clone PI V" are: Its reduced power consumption to 120mA at maximum volume and full LEDs on. As well as the closest to the original metal detector (From which the Clone was copied) stability of work.
The reduction in power consumption was achieved by removing the energy-intensive screen. And the stability of the metal detector was improved by the use of TL431 as a source of reference voltage.
Diagram of the Clone PI W metal detector
Also in this file, you can download the circuit diagram and printed circuit board for the Clone PI V metal detector in .pdf format ( Scheme and layout of the printed circuit board from the site of the developer of the metal detector, a link to the author's site at the end of the page).
Here is the fee offered by the Clone developer:
But personally, I prefer the version of the printed circuit board for Clone B from DexAlex, (it is on it that most radio amateurs assemble this metal detector):
An archive with modifications from DexAlex, firmware (1.0.1), a schematic and printed circuit board in the Sprint Layot format and other useful materials for making a metal detector on your own can be downloaded in this archive -
Latest firmware for Clone PI W metal detector (Version 1.2.4) —
When flashing the controller, the configuration bits must be arranged as follows:
Assembling a metal detectorclonePIw DIY
Assembling the metal detector, you should start by choosing a printed circuit board option. Since they have slight differences in the components used. We recommend choosing the DexAlex version, his version of breeding this and other metal detectors, have proven themselves perfectly.
Then we buy parts. Attention should be paid to the following components: it is better to use ceramic capacitors, and even better film capacitors, this will positively affect the stability of the work. The construction resistor must be of good quality and multi-turn, single-turn cheap racks are unsuitable here! TL431 and the resistors in its harness also deserve special attention and should be 100% quality.
We poison and assemble the printed circuit board, flash the microcontroller and start the metal detector. To power the metal detector Clone PI V, you can use 8 finger batteries, or 12 batteries. "Krona" will not work! Also, when turning on the metal detector for the first time and setting it up, you must use new batteries or a fully charged battery. In the power circuit, it is recommended to use a protective diode against “reverse polarity” and a fuse, this will help protect your metal detector from your own negligence, especially at the stages of its assembly and testing!
If your metal detector did not work right away, then in troubleshooting, a voltage map can help you -
Here is an example of an already assembled electronic unit of the Clone PI W metal detector:
Making a coil for a metal detector Clone PI W
A standard coil for the Klon PI V metal detector can be made by winding it on a mandrel with a diameter of 19-20 cm, 25 turns, with a wire of 0.7-0.8 mm in diameter. You can increase the diameter of the coil, this will have a positive effect on the depth of detection, but then you should reduce the number of turns. With a coil diameter greater than 28-30 cm, sensitivity to small objects will begin to decrease, this should also be taken into account. You can read about other ways to make a coil for a Clone metal detector.
Instructions for controlling the Clone PI W metal detector
Metal detector control Clone PI V, is carried out using 6 buttons. The buttons have the following purposes:
- S1"Barrier-"/"Guard interval-"
- S2"Barrier+"/"Guard interval+"
- S3"Volume-"/"Up min-"
- S4"Volume+"/"Up min+"
- S5 Function not yet assigned
- S6 Zero (0)
- S5+S6"Setting mode"/"Exit setting mode"
A sign of being in the settings mode (ie, where you can set the guard interval and the minimum allowable supply voltage) is the glow of the last LED (VD13).
The guard interval is displayed very approximately, the number of LEDs on the left must be multiplied by 8. After turning off the power of the metal detector, the value is not saved!
The minimum allowable voltage is displayed in increments of 0.5 volts, from 7.5 to 11 volts. The default value is 8 volts. The value is saved. If the supply voltage drops below the set value, the device continues to work, but every 15 seconds it produces a double low sound.
We also found on the net, reworked Clone PI W metal detector manual(Reworked from the instructions from Koshchei), it can also be useful to you -
Setting up the Clone PI W metal detector
The Clone PI W metal detector does not need complex settings. The whole setup is as follows: We turn on the metal detector away from metal objects, and wait until the entire scale of the LEDs has passed. Then we bring a reference metal object (for example, a coin) and check the sensitivity of the metal detector. Then we tighten the tuning resistor, reboot the metal detector and check the sensitivity again. We repeat the manipulation until we achieve the best result!
After you have finished the adjustment, in the metal detector you can also use the control buttons to adjust the volume and sensitivity of the metal detector. The higher the Barrier (adjustment range 0 – 10), the lower the sensitivity. We lower the threshold until false alarms appear, with the metal detector coil raised into the air. For a normally assembled and tuned metal detector, the normal threshold is 3-5.
It should also be remembered that when turning on and resetting the metal detector, there should not be any metal objects in the coil area, otherwise the metal detector will lose part of its sensitivity!
This completes the setup of the metal detector, and you can start searching!
You can read about the manufacture of coils for the Klon B metal detector, and about the manufacture of deep frames.
Conclusion: The Clone PI W metal detector is a great option for self-assembly. Quite affordable components, a simple circuit, the presence of open firmware and a lot of necessary information, all this will help you in its manufacture. The disadvantages include its higher noise sensitivity than that of Traker and Koshchei, and therefore higher buggy. This is especially acute near electromagnetic and industrial sources of interference. But in general, the metal detector turned out to be quite worthy!
Video of the homemade metal detector Clone PI W
Video test of the Clone Pi V metal detector assembled by yourself, with a large coil 40 cm:
When writing this article, materials were used from the websites of the metal detector developer - http://fandy.hut2.ru/ClonePI_W.htm
And also forums where this scheme is discussed: http://forum.cxem.net/index.php?showtopic=47662 and http://md4u.ru/viewtopic.php?f=5&t=2144
Downloads:
Schematic and printed circuit board of the Clone PI-W metal detector (From the author) —
A printed circuit board from DexAlex, firmware 1.2.1 and other materials and photos for self-assembly of the Clone PI W metal detector —
Option from the board and assembly of the metal detector from Korvin, as well as a voltage map and some useful materials, for example, a printed circuit board option, with the replacement of the KH5 chip -
.
The scheme is not complicated and has been chewed many times on the Internet, and I describe my version and the difficulties that I had to face when repeating this design. The setting is a bit more complicated, which, in other matters, a more or less trained radio amateur can handle if he puts his attention and effort. It turned out to be the most confusing thing to buy a normal operational amplifier, at first glance, microcircuits of this type are not in short supply, but the quality of parts from some manufacturers turn the purchase into a “guess” game. The maximum parameters of this metal detector depend on the quality of this microcircuit, here there are increased requirements for this part. This is a quad amplifier TL074. In addition to the operational amplifier, you also need the not very common ADG444 comparator and the ATmega-8 microcontroller.
When designing a printed circuit board, due attention should be paid to the arrangement of elements, the circuit of operational amplifiers and the comparator away from the coil circuit, the ground, if possible, to each block is separate and the distance between the tracks, and this is important for SMD mounting, at least 0.3mm. at smaller inter-track distances, it will be problematic to keep the board completely clean, and cleanliness is the key to the normal operation of the device.
With a wide variety of board layouts for this design, I had to make my own under the factory KM35BN case, which is available.
One of the wiring options.
He bred all his board options for SMD elements.
Device boards before final assembly.
In the scheme, some replacement parts are possible.
Operational amplifier:
In order from worst
TL084
TL074
LF347
MC33079
OPA4134PA.
The TLC274 chip gave me not bad results. Many people use dual amplifiers like TL072. The archive has a wiring for this version of the board.
The ADG444 comparator can be replaced with a DG441, KR590KN5, or rewired with a KR590KN2, with an optional signal inverter on the 4066.
Microcontroller Atmega8-16PI, Atmega8-16PU or Atmega8A-PU.
Stabilizer 78L05 can be replaced with a similar one from other series.
Pay special attention to the quality of capacitors C3 and C5, the stability of work depends on them. Chinese Mylar capacitors used in measuring instruments do not work badly. Their denominations can be changed within the limits indicated in the diagram. Usually a selection is needed for low sensitivity or arousal.
The operation showed that the tuning resistor R7, with a nominal value of 1 K, must be made remote and preferably multi-turn (when wiring the board, I initially installed SMD, I had to change it).
The firmware of the microcontroller can be done directly on the board by turning off the power section and soldering the wiring to the main signal outputs.
When flashing, the fuses were set as in the picture, reversed, so you need to set them in Pony-Prog and in some shells of the AVRDUDE program, for example, I sewed with such fuses in the USBASP_AVRDUDE_PROG program with the USBASP programmer
Popular firmware:
Firmware version 1.2.5: CPI_W_125.zip.
An attempt to weaken the influence of the soil.
The search mode is purely dynamic.
Firmware version 1.2.4: CPI_W_124.zip is the most suitable
Sensitivity increased by a couple of centimeters.
Barrier values for regulation: 1 - 2 - 4 - 8 - 16 - 32.
Added overload signal.
Slightly reduced sensitivity recovery time after overload.
search mode dynamic/static, otherwise the same as in 1.2.5
Bugs fixed.
Firmware version 1.2.2m: CPI_W_122m.zip
Option without oversampling, the rest is similar to version 1.2.4.
however, it has a progressive barrier step. This means that it is set to 0 - 2 - 4 - 8 - 16 - 32
Firmware version 1.2.2: CPI_W_122.zip.
The input filter has been changed.
Press the button "Zero" made silent.
Fixed minor bugs.
Button assignment:
S1 "Barrier-"/"Guard interval-"
S2 "Barrier+"/"Guard interval+"
S3 "Volume-"/"Up min-"
S4 "Volume+"/"Up min+"
S5 Function not yet assigned
S6 "Zero" (0)
S5 + S6 "Setting mode"/"Exit setting mode".
Sensor - 25-27 turns of enameled copper wire with a diameter of 0.5 ... 0.8 mm. It is wound in bulk on any mandrel with a diameter of 19 cm or more. The larger the diameter of the coil, the higher the sensitivity of the MD (for small objects, it is true somewhere up to a coil diameter of 28 cm) and the fewer turns the coil should contain. With the cable, the inductance of the sensor should be within 400uH, the resistance is usually 1.5-2 ohms.
The design of my planar sensor consists of 3 concentric coils with smaller diameters d1 - 13.8cm - 9 turns, d2 - 16cm 14 turns, d3 - 18.2cm 12 turns, wire 0.5mm bare coil inductance 392uH.
The power supply of the device is 9-16v. The current consumption can reach 120 mA. When the supply voltage drops to 8V (by default, it is changed with the buttons in the setup mode), the device starts to produce a characteristic double signal every 15 seconds. At the same time, it continues to work up to about 6.5v. at the same time, only the sound volume decreases, the sensitivity to metal in the range from about 8 to 16V remains at the same level (thanks to the exemplary voltage source on TL431). When setting up, a stable voltage source is especially important, you do not need to use unverified pulsed sources, Krona and salt batteries are also excluded. It is better to take a 12v battery for 4-40 A / Hours and set it up with it. 3 cans of LI-ION from a laptop work fine for me.
The setting should be carried out far from industrial interference and large metal objects, it is better in nature, outside the city. When setting up, we take the sensor away from metal and other objects, or simply turn it up and turn it on. A scale of ten LEDs lights up, slowly decreasing to zero, with a corresponding sound - this device adjusts to the sensor and the environment, taking it as the "no metal" position. With a "perfect" coil and the correct trimmer adjustment, all LEDs should go out completely. If at this moment there is any metal object near the sensor coil, the device, of course, will not be configured correctly. After that, a characteristic sound signal sounds, notifying that the device is configured. We bring it to the metal and check - the closer the metal, the farther to the right the "light" moves on the scale and the higher the sound becomes. Twisting the resistor, we adjust to the maximum flair (after each adjustment, we must take it away from the metal and press the "reset" button - the "lights" at the same time beautifully, with sound, run to the center of the scale). Everything, the device is set. Let's play with the buttons. Two buttons adjust the sound ("more" and "less"), two more adjust the "barrier" - this is the reciprocal of sensitivity - and not to be confused with adjusting the flair! By pressing "more" or "less" (maximum - 10, minimum - 0), we set such a barrier at which the flair of the device will be maximum with satisfactory stability. However, if the barrier has to be heavily roughened - up to the 7th and higher LED, then this is no longer good. It is necessary to move away from industrial interference (forest, field) and also adjust the trimmer. A well-tuned device does not give false positives with 3-4 LEDs.
The sixth button - "service", in the device makes it possible to adjust the voltage at which the battery discharge alarm is triggered (by default - 8v). At the same time, the device continues to work until the batteries are completely depleted, only every 15 seconds it gives out a characteristic double beep. This button allows you to adjust the guard interval - well, this is necessary for experimental sensors.
If you can’t set it up, there are a lot of false positives, or poor sensitivity, you will have to take up a soldering iron. Usually, with normal details, this should not be the case. By increasing the value of R15 and decreasing the value of C5, you can raise the flair of the device to the maximum. The ratio of the resistances of the resistors R1 and R3 also has a great influence on the flair, and, as it was said, the operational amplifier. In case of false positives, work with these elements in the reverse order, that is, slightly dull the feel. Although with some opamps, the false ones always go to the most stupid instinct, they have to be changed.
Well, it is clear that the final adjustment must be made with a standard sensor, with a standard cable on a standard rod in a standard situation.
Clone Pi AVR this is a simplified and improved version of the metal detector popular with radio amateurs. Since in the manufacture of the Clone PI metal detector, many had difficulties with the acquisition of an ADC, in the new version of the Clone PI metal detector AVR, the Peak controller and an external ADC were replaced by an affordable AVR microcontroller with an internal ADC Atmega8.
Scheme of the metal detector Clone PI AVR
As well as the Clone PI AVR circuit with the specified DC voltages
On the Internet, there are several options for breeding a printed circuit board for a Clone Pi AVR metal detector. Below is a photo of a quite decent version of the PCB.
In this archive you can download: a printed circuit board in *.lay format, a diagram, firmware and photos of the stages of manufacturing a metal detector board.
To flash the microcontroller, the configuration bits must be arranged as follows:
Metal detector Clone PI AVR has an average level of complexity manufacturing, due to the presence in the metal detector circuit, of a programmable microcontroller. But otherwise, its manufacture should not cause any special difficulties.
Coil for metal detector Clone PI AVR
With the Clone PI AVR metal detector, you can use coils from the Tracker and Koschei pulse metal detectors, as well as large depth frames.
The most versatile coil diameters are 20-30 cm. Such coils will have a detection depth of 1 - 1.5 meters and will remain sensitive to small metal objects (coins, jewelry, etc.).
For the manufacture of a universal search coil, you need to wind 23-24 turns of winding enamel wire with a diameter of 0.7-0.8mm on a mandrel 26-27 cm. As a mandrel, you can use a saucepan of a suitable diameter, or make a mandrel as in the photo below:
To make a mandrel, we take a sheet of plywood or chipboard. On it, with the help of a compass, we draw a circle with the diameter we need. Then we take screws or self-tapping screws, we put cambric on them. We screw the screws with cambrics around the perimeter of our circle, and we get a mandrel for winding the coil.
The coil is wound in bulk. Then the turns are tightly wound together, with adhesive tape, or electrical tape. We solder the wire 2 * 0.75 mm in insulation to the ends of the winding.
We connect our coil to the board of the Clone Pi AVR metal detector (It is better to use a connector for connection) and check its performance. Such a coil is suitable for testing and experimentation, but for real work, it should be protected from shock, moisture, etc.
To do this, the coil must be fixed in a suitable plastic case. In our designs, we use such a universal case.
The coil is fixed inside the body with hot glue, and then the coil body is sealed with dichloroethane, or twisted with stainless steel screws.
To obtain an underwater coil, it is better to fill the body with epoxy. This will reduce its buoyancy and prevent water from entering the inside of the hull.
Firmware for metal detector Clone PI AVR:
- Firmware version 1.7.3 for ATmega8 - CPI_PRG_173_AVR
- Firmware version 1.7.3A for ATmega8, with modified auto-ground algorithm - CPI_PRG_173a_AVR
- Firmware version 1.8.0 for the controller ATmega8- CPI_PRG_180_AVR Changes:
- The volume of the button sounds has been adjusted to match the main volume.
- Ground adjust now works in 3 modes - adaptive, fixing And off(static).
- Guard interval can now be picked up when enabled ( auto), use the stored value ( last), or be selected by the user forcibly in the range 2 … 80 .
- Added option volume raise, which allows you to reduce the volume at the beginning of the scale (with weak responses). This improves the stability of the circuit at a low threshold.
- Removed double power mode, which showed its practical uselessness.
- When the backlight is on, the letter “L” (Light) is displayed on the indicator.
- Firmware version 1.8.1 for the controller ATmega8, bugs fixed in the firmware and power consumption reduced – CPI_PRG_181_AVR
Conclusion: Clone PI AVR metal detector This is a proven and popular metal detector among radio amateurs and search engines. It has a search depth comparable to factory metal detectors and a completely open circuit and firmware for its manufacture. TO shortcomings metal detector should be attributed to excessive power consumption.
Video of the launch of the Clone PI AVR metal detector assembled by oneself, and the possibility of setting it up:
Materials used in the writing of this article:
- Developer site - http://fandy.hut2.ru
- And this site - http://metdet.ucoz.ua/publ/metalloiskatel_klon/1-1-0-13
- And also a forum - http://md4u.ru/viewtopic.php?f=5&t=660 - here you can ask questions about self-assembly of the metal detector.
