Hi all! I haven't written here for a long time. There was a lot to do... It’s already spring outside, the temperature for the second day remains at 9-10 degrees. The snow is slowly melting. The opening of the season is just around the corner. So, one of the things that would help pass the time and bring the season closer would be to assemble a metal detector from scratch with your own hands. I was pleased with the result :)
For those who can't wait, here's a video of this miracle in action:
It all started with the fact that I finally acquired a foil PCB without paying a penny for it)). The first step for testing this PCB was assembling the metal detector.
For assembly, the “Pirate” pulse metal detector circuit was chosen, because there was no desire to make a device with beats). So, the circuit has been downloaded, the Sprint Layot program has been installed, and the printed circuit board has been printed on photo paper. I'm starting to assemble.
The board was made using the laser iron method (abbreviated as LUT). I won’t go into detail, there’s Google for that matter :). That's it, the PCB is cut out, the tracks are transferred to the board.
Next I dilute the etching solution. And then the electrolyte from the battery helped me again! The solution included table salt, hydrogen peroxide and electrolyte (in the evening of the same day, a kitten knocked over the jar with the solution).
Well, the board is etched and the holes are drilled. Now she needs to be tinned. Tinning was done with a soldering iron.
The longest stage of assembly has arrived. Namely, collecting, searching and soldering parts. Both microcircuits and two transistors were found without difficulty. Capacitors and resistors were pulled from old boards. But I didn't have several resistors. I had to go to the TV workshop to get them. They gave them to me for FREE.
The board is assembled, the experimental coil is wound. The moment of inclusion has come. The first power-up was made from a twelve-volt power supply. I twisted the wires, connected the coil, double-checked the polarity, turned it on... it didn’t work... it was silent (. The transistor was heating up. I re-soldered it. I turned it on again... silence. Subsequent checks revealed a malfunction of the K157UD2 microcircuit. The next day a new one was found and the start-up was repeated. And then the assembled circuit showed signs life. It works!!! There was a lot of joy :)
The next day the scheme was established and received a cultural building. The connectors have been removed. Now I needed a normal coil. I cut it out of a piece of plywood. Then I selected the number of turns, filled the winding with hot glue and wrapped it blue electrical tape.
Now material for the rod was needed, which was what the next day was devoted to. I bought 4 meters of PVC water pipe and 0.5 meters of sewer pipe. The corresponding parts for assembling the rod were cut out of them. The pipes were soldered using hot glue and a hair dryer. 
The rod is assembled, the coil is ready, the body of the device has acquired the proper appearance. All that remains is to combine everything. The block is attached to the rod using fittings. But there was no plastic bolt in the store to secure the reel. The coil is temporarily held on the tie.
All that remains is to buy a battery with charger. It also works with a battery from a screwdriver :).
At home, the device begins to respond to a nickel from 20 cm, which I think is not bad. I will also say that it does not discriminate, so it is impossible to cut off the trash metal that is so hated by all diggers.
I received complete satisfaction from the assembly process and the results obtained and, I think, slightly improved my amateur radio skills by applying new methods in my practice.
So, my investment (except for the purchase of a battery) cost 230 rubles. With a battery, I think it will be about 1000 rubles. This device can easily be repaid and even earned by searching for scrap metal with its help. Searching for coins is also possible, but due to the lack of discrimination, it will be difficult.
I'll tell you about the photographs. I made them for myself, so their quality is a little thin :)
I also advise you subscribe to the channel “Old Vyatka”, where you will find a lot of videos about digging, metal detectors, navigation, cartography and coin care:
Powered metal detector pirat, from 12 volts, you can use regular batteries, but it is better, of course, to take a good battery, for example from a screwdriver. Personally, I use it, or rather the batteries that are in it.
Search coil metal detector Pirate, wound on a 190 mm frame. and contains 25 virks, PEV wires 0.5 mm.
- Current consumption 30-40 mA
Pirat metal detector diagram:
Chip NE555:
Transistor IRF740:
Variable resistors:
This is how it should work:
For K157UD2 it is better to install an adapter socket, and for NE555 You can also install it, it won’t hurt!))
The lady conducted tests on a medium reel with a diameter of 15 cm. So the gold ring caught in the air at 18 cm, scissors 30 cm. table lamp 50cm. which isn't bad enoughThe circuit of the “Pirate” metal detector is very simple and understandable even for novice radio amateurs. It consists of two microcircuits that do not need to be flashed or programmed. It is very easy to assemble, you just need to solder all the parts in the right places!))
Attention! I make custom MD “Pirate”, write to kavinskiy on Skype or write comments! Thank you!
The pirat metal detector is powered by 12 volts, you can use regular batteries, but it is better, of course, to take a good battery, for example from a screwdriver. Personally, I use it, or rather the batteries that are in it.
The search coil of the Pirat metal detector is wound on a 190 mm frame. and contains 25 virks, PEV wires 0.5 mm.
Metal detector characteristics:
Current consumption 30-40 mA
Reacts to all metals, no discrimination
Sensitivity 25 mm coin - 20 cm
Large metal objects - 150 cm
All parts are inexpensive and easily available.
Required parts for assembly:
pirate_details
Pirat metal detector diagram:
ON UD2 (1)
The circuit uses 2 microcircuits (NE555 and K157UD2). They are quite common. K157UD2 - you can pick it out of old equipment, which I did with success.
pirate_microshema1
Chip NE555:
NE555N
Transistor IRF740:
pirate_transistor_1
Variable resistors:
pirate_rezistor_1
Be sure to take 100nF film capacitors, like these, take the voltage as low as possible:
pirate_condensatori
Print out the board sketch on plain paper:
pirate_pechatka_1
We cut a piece of textolite to its size:
pirate_pechatka_2
We apply it tightly and press it with a sharp object in the places of future holes:
pirate_pechatka_2
This is how it should work:
pirate_pechatka_3
pirate_pechatka_4
pirate_pechatka_5
After drilling, you need to draw tracks. You can do this through photoresist, LUT, or simply paint them with Nitro varnish with a simple brush. The tracks should look exactly the same as on the paper template. And we poison the board.
pirate_pechatka_6
pirate_pechatka_7
pirate_pechatka_8
For K157UD2 it is better to install an adapter socket, and for NE555 you can also install it, it won’t hurt!))
pirate_montag_1
pirate_montag_2
pirate_montag_3
To wind the search coil you need a copper wire with a diameter of 0.5-0.7 mm
pirate_wire
I wound the coil on a simple pan, 190 mm in diameter. After which, I wrapped everything with duct tape:
pirate_katuschka
According to the diagram, the coil has a diameter of 19 cm and contains 25 turns. I’ll immediately note that the coil needs to be made of such a diameter based on what you will be looking for. The larger the coil, the deeper the search, but a large coil does not see small details well. The small coil sees small details well, but the depth is not great.
I immediately wound three coils of 23cm (25 turns), 15cm (17 turns) and 10cm (13-15 turns). If you need to dig up scrap metal, then use a large one; if you are looking for small things on the beach, then use a smaller reel, but you’ll figure it out for yourself.
pirate_katuschka_3
pirate_katuschka_2
The coil should be as level as possible. The speaker took the first one he came across.
Now we connect everything and test the circuit to see if it works.
After applying power, you need to wait 15-20 seconds until the circuit warms up. We place the coil away from any metal, it is best to hang it in the air. Then we begin to twist the 100K variable resistor until clicks appear. As soon as the clicks appear, turn it in the opposite direction; as soon as the clicks disappear, that’s enough. After this, we also adjust the 10K resistor.
Regarding the K157UD2 microcircuit. In addition to the one I picked out, I asked one more from a neighbor and bought two at the radio market. I inserted the purchased microcircuits, turned on the device, but it refused to work. I racked my brains for a long time until I simply installed another microcircuit (the one I removed). And everything started working right away. So this is why you need an adapter socket, so that you can select a live microcircuit and not have to worry about desoldering and soldering.
Everything is ready, all that remains is to make a rod and place the board in the case and look for treasures)
pirate_gotoviy
And lastly, I’m throwing in a video of a pirate at work!
The lady conducted tests on a medium reel with a diameter of 15 cm. So the gold ring caught in the air at 18 cm, scissors 30 cm. table lamp 50cm. which is not bad enough for such a metal detector.
You can download the printed circuit board in Sprint-Layout format here!for such a metal detector.
Metal detector circuit board
You can download the printed circuit board in Sprint-Layout format!
In this detailed article we will talk about how to make a pirate metal detector yourself and with your own hands, we will break everything down, all aspects of its assembly. Starting from the principle of operation to the list of popular faults.
First, a little history, where this device came from, what are the reviews from diggers, and let’s look at its characteristics.
Pirat is not a conqueror of the sea at all, but an abbreviation. PI means that this metal detector is pulsed, and rat is the website of the author of this MD, radioscot. As for the reviews, the pirate has gained fame as a simple and inexpensive device; usually novice detector creators start with it. Reliability depends on the author and the quality of his build. After assembly, it is immediately ready for use and does not require any configuration.
Characteristics of the pirate metal detector:
Here, a lot also depends on the creator of this device, the parts used and the diameter of the coil. Let us give, as an example, the value declared by the author:
- Supply voltage 9 – 12 volts.
- Current consumption 30-40 mA.
- Coin detection depth (25mm) – 20 cm.
- The detection depth of large metals is 150 cm.
Parts List:
The list of necessary parts for the pirate metal detector is attached as an image below. All these radio components are not difficult to get, with the exception of the comparator microcircuit, it is relatively rare, but you can find it in stores; there are enough of them in old Soviet technology. Now the question of what parts are needed has disappeared, let's move on.
Pirate metal detector circuit
The classic pirate circuit diagram is based on the ne555 chip, here is its drawing.
Pirate metal detector circuit for NE555
This electrical circuit consists of two blocks - a pulse generator and a comparator. Briefly, the operating principle is as follows: a pulse generator sends its pulses to one input of the comparator, and a pulse from the coil is supplied to the second input of the comparator. If there are signals at the two inputs of the comparator, then there is one at its output too, the signal from the output goes to the speaker, and it notifies us - there is metal here. In addition, there are diagrams on the Internet, MD pirate using tl072 and k561la7 microcircuits. No specific information was found on k561la7, so if you have anything to say about this, we are waiting for you in the comments and will definitely add it to the article.
Pirate metal detector circuit using transistors
This is the second version of the scheme from the developer. What is used here as a generator is not a microcircuit, but transistors, in the original version the Soviet KT-361 and KT-361. But no one prohibits experiments; other transistors with similar parameters will work well.
Circuits for microcontroller versions: Pirate 2, Pirate 3, Pirate 4 will not be included. As for the scheme for gold, there is no need for any separate manipulations. It is enough to assemble an ordinary pirate and test it; it should react to any metals. Some people need to download patterns for printing, you can click on the image and save it to your computer. If you redesigned the circuit yourself, we will be happy to add your version to the article.
So we talked in detail about the pirate metal detector circuit.
Pirate metal detector board
Transistor board
Here, by the way, is the board for tl072, if anyone is interested. On SMD parts.
Board sizes:
- On transistors - 30x76.
- On NE555 - 30x80.
- SMD on TL072 - 26×35.
Pirate metal detector coil
Now let's talk about how to make a coil for a pirate metal detector with your own hands.
There are many variations of coil winding. The classic option is to take a 0.5 PEV wire and wind 25 turns on some frame with a radius of 19-20 cm. It is recommended to solder directly, and once the whole circuit is working, start experimenting with various plugs and adapters. If you like twists, there shouldn’t be any; sensitivity greatly depends on this.
Some people make a coil for a pirate metal detector from twisted pair. This is a very good reel option. To make it, we need approximately 2.5 - 2.7 twisted pair wires. We find the middle and make a mark, then we make a ring and also mark it as in the figure below. We fix this whole thing and begin to bend the ends of the ring on both sides. This must be done tightly, without gaps. There should be about 3 turns.
Wire pinout for twisted pair coil
Depth coil for pirate metal detector.
To increase the depth and sensitivity of a pirate metal detector, you need to properly make a coil. The technique is as follows:
- We wind 25 turns.
- We test by unwinding one turn at a time and cutting them off, the sensitivity will increase.
- We find the moment when sensitivity begins not to increase, but to decrease.
- We calculate the number of turns and wind a new coil with this number of turns + 1 or 2 turns.
- Maximum sensitivity has been reached.
This increases the pirate's sensitivity. A lot also depends on the quality of the tracks. You can also play around with resistor R7.
Parameters at which the maximum depth was achieved:
- Number of turns - 10.
- Coil resistance is 2 Ohms.
- Wire thickness – 0.45.
- Diameter – 20 cm.
- Resistor R7 – 75 Ohm.
Setting up a pirate metal detector
Does not require special setup. All you have to do is assemble the board and turn it on. After 5-10 seconds it starts making sounds. Using variable resistors, we adjust this sound until it clicks - ready, this is maximum sensitivity, shovel in hand and go.
Metal detector pirate does not work
Let's look at the list of malfunctions, their causes and ways to eliminate them.
Malfunction: After assembly there are no signs of life.
Remedy: If you soldered with solder pastes or any acids, it is highly recommended to wipe the board with alcohol and dry it. If this does not help, then you need to check every part for serviceability, these are the main reasons.
Malfunction: NE555 or another part is heating up.
Remedy: check the tracks for short circuits, check the ratings and serviceability of all parts. Look at the tips from the first malfunction and go through them.
Metal detector pirate with metal discrimination
Metal detector pirate underwater
Usually a collected pirate is ready for underwater hunting. The main thing is to well insulate the housing and coil - the entire electronic part. Well, we need to come up with something with an indication. If, of course, you don’t dive with it, then you can leave everything as it is, but under water, you won’t hear any sound. Usually, for such purposes, a light indication is made.
Modernization of the pirate metal detector
Because the pirate is very simple, it is very easy to layer various gadgets and improvements on it. We will now look at some of them.
Tone sound.
It is very easy to attach a tone to the pirate, you will see the circuit and PCB below.
Battery discharge monitoring circuit
Here are a few improvements, use them for your health.
Conclusion: here we have figured out how to make a pirate metal detector yourself. The article is quite complete, but, like everything, it is imperfect. If you have any additions to it, we are waiting for you in the comments below.
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The “digging” season has begun; for those who are not in the know, I’ll explain that this is a search for artifacts using a metal detector.
Recently, more and more people, regardless of gender and age, are infected with the excitement of quickly finding
treasure and thereby ensure a happy life. In this business, first of all, you need luck, but good
The tool that is the metal detector is also not in last place. Today they offer a big
a choice of metal detectors of varying complexity and functionality; accordingly, the price for such devices is not small.
But most people try to buy cheap devices because it is possible to call such a product a metal detector
only conditionally. Having wandered around the local outskirts with such a unit, “treasure hunters” come to the understanding of finding something
serious is not possible. Having read on the forums how to modernize without having the slightest knowledge of radio electronics
Such a device and not losing the money spent on its purchase, people get to work. At the end of this process
After improvements in this way, the metal detector no longer shows signs of life. It seems like I need to stop
But some people start making “clones”, and the end result is a device that is much worse in terms of its parameters than the original.
In confirmation of the above, a “Pirate” metal detector was recently brought in for repair, in addition to a non-working board.
own production.
As always in this case, in disassembled form, the cut off wires connecting the coil and the board survived
creative torment of a radio amateur/treasure hunter. The original factory board has also undergone serious interference,
torn off printed conductors and many missing radio elements.
The board trace is similar to the drawings and diagrams described in many forums where
questions regarding the Pirate metal detector.
It was necessary to restore the printed tracks and install radio elements according to the diagram in order for it to work as before,
that is, at least “no matter what, no matter who,” but he reacted. I didn’t really want to take on this job, I overcame it
Interested in comparing a really working copy and what they write about it on the forums. After everything has been fixed
Disadvantages of the “modernization” The device began to work, it was decided to look at the waveforms on the legs of the microcircuits with an oscilloscope.
All measurements were carried out relative to the minus power supply, connected by a coil, supply voltage 12V, oscilloscope input
closed.
There is no need to describe the operation of the circuit, since many topics have been created on different forums on this issue,
but I was interested in the operation of the comparator and the pulses on the power bus.
Let's look at several oscillograms of how the comparator turn-on signal is generated.
Pin 5 - yellow.
Pin 6 - blue.
With the onset of the measuring pulse, the discharge of capacitor C5 begins through the chain R12 and R13.
The voltage at the 5th input of the comparator begins to decrease, at the 6th the decrease occurs more slowly,
thanks to capacitor C6, resistors R14, R15.
If the measuring pulse is long enough, then at some point in time the voltage at C5 will drop
so much so that the 5th pin of the comparator will change the polarity of the relative 6th pin. Output 9 will appear
a positive pulse amplified by transistor T3, the load is a speaker and a limiting resistor.
Almost in the dynamics we hear the comparator switching.
Pin 9 - yellow.
Pin.6 - blue
Interference from switching transistor T2, the pulse amplitude is greater than 2V, a period of 24ns is visible along the power bus.
The same pulses can be seen on the measuring signal pin13.
This interference is generated when transistor T2 switches. It is possible to reduce pulses if there is a gap in the power bus
plus 12V, install a choke and a 10uF16V tantalum capacitor. The PCB topology allows you to install a filter
towards the receiver, the master oscillator and the output transistor stage are less susceptible to interference, such
protection for them is ineffective.
Oscillograms at other points in the circuit.
NE555
Pin 2. Pin 3.
Pin 5. Pin 7.
K157UD2
Conclusion 3. Without the presence of metal. Conclusion 3. Presence of metal.
Conclusion 5. Without the presence of metal. Conclusion 5. Presence of metal.
Conclusion 9. Without the presence of metal. Conclusion 9. Presence of metal.
Conclusion 13. Without the presence of metal. Conclusion 13. Presence of metal.
T2 - IRF740
Gate. Stock.
List of radioelements.
R1 resistor 1 kOhm
R2 resistor 1.6 kOhm (possible replacement 2.6 kOhm)
R3 resistor 100 kOhm
R4 resistor 470 Ohm
R5 resistor 100 Ohm
R6 resistor 150 Ohm
R7 resistor (1 W) 220 Ohm (possible replacement 390 Ohm.)
R8 resistor (0.5 W) 390 Ohm
R9 resistor 47 kOhm
R10 resistor 62 kOhm
R11 resistor 2 MΩ (possible replacement 3.3 MΩ)
R12 resistor 27 kOhm
R13 variable resistor 50 kOhm
R14 resistor 62 kOhm
R15 resistor 120 kOhm
R16 resistor 470 kOhm
R17 resistor 10 Ohm
R18 resistor 10 kOhm
DA1 chip NE555 (analogues: AN1555, 1006VI1)
DA2 chip K157UD2
C1 capacitor (film) 100 nF
C2 capacitor (film) 100 nF
C3 capacitor (electrolyte) 1 µF/16V (possible replacement 4.7 µF/16V)
C4 capacitor (electrolyte) 10 µF/16V (possible replacement 22 µF/16V)
C5 capacitor (ceramic) 1 nF
C6 capacitor (electrolyte) 10 µF/16V (possible replacement 22 µF/16V)
C7 capacitor (electrolyte) 1 µF/16V
C8 capacitor (electrolyte) 2200 uF/16V
T1 transistor BC557 (analogues: KT361, KT502, KT3107)
T2 transistor BC547 (analogues: KT3102 - BC546; KT503)
T3 transistor IRF740
D1 diode 1N4148 (analogues: KD521, KD522)
D2 diode 1N4148 (analogues: KD521, KD522)
BA1 speaker 8 ohm
PW1 power supply 12 Volt
After repair and testing, the search is “on the ground”. My findings: a rusty can lay underground at a distance of about ten
centimeters, and, in small details, several small pieces of metal somewhere at approximately the same depth. Bad
I turned out to be a treasure hunter, I won’t make such a device for myself (though I didn’t even intend to do this repair),
especially to buy such “handjob”. To all those who hope for the smile of Fortuna, the ancient Roman goddess of luck, my notes,
might come in handy.
Good luck "coping".
Recently, an activity such as searching for various ancient coins, household items, and just metal trinkets in the ground using a metal detector has become very popular. In fact, what could be better than taking a walk through the field in the morning, inhaling the smells of nature and enjoying the views. And if at the same time you manage to discover some worthwhile find in the ground, then it’s a fairy tale. Some people do this on purpose, spending days combing fields in search of valuable coins or other valuables. They have at their disposal expensive factory-made metal detectors, which not everyone can afford to buy. However, it is quite possible to assemble a full-fledged metal detector yourself.
This article will discuss the creation of the most popular, sought-after, time-tested, reliable pulse metal detector called “Pirate”. It allows you to find coins in the ground at a depth of 15-20 cm and large objects at a distance of up to 1.5 m. The diagram of the metal detector is presented below.
Metal detector circuit "Pirate"
The entire circuit can be divided into two parts - transmitter and receiver. The NE555 microcircuit generates rectangular pulses, which are fed to a coil through a powerful field-effect transistor. When the coil interacts with metal located next to it, complex physical phenomena occur, thanks to which the receiving part has the ability to “see” whether there is metal in the coil area or not. The receiver chip in the original Pirate circuit is the Soviet K157UD2, which is now becoming quite difficult to obtain. However, instead of it, you can use the modern TL072, the parameters of the metal detector will remain exactly the same. The printed circuit board proposed in this article is designed specifically for installing the TL072 chip (they have different pinouts).
Capacitors C1 and C2 are responsible for generating the frequency of rectangular pulses; their capacitance must be stable, so it is advisable to use film capacitors. Resistors R2 and R3 are responsible for the duration and frequency of the rectangular pulses that the microcircuit generates. From its output they are supplied to transistor T1, inverted and fed to the gate of the field-effect transistor. Here you can use any sufficiently powerful field-effect transistor with a drain-source voltage of at least 200 volts. For example, IRF630, IRF740. Diodes D1 and D2 are any low-power ones, for example, KD521 or 1N4148. Between pins 1 and 6 of the microcircuit, a variable resistor with a nominal value of 100 kOhm is connected, with which the sensitivity is set. It is most convenient to use two potentiometers, 100 kOhm for rough adjustment and 1-10 kOhm for fine adjustment. You can connect them according to the following scheme:
The speaker in the circuit is connected in series with a 10-47 Ohm resistor. The lower its resistance, the louder the sound and the greater the consumption of the metal detector. Transistor T3 can be replaced with any other low-power NPN transistor, for example, with the domestic KT3102. You can use any speaker you find. So, let's move from words to action.
Metal detector assembly
List of required parts
Chips:- NE555 – 1 pc.
- TL072 – 1 pc.
- BC547 – 1 pc.
- BC557 – 1 pc.
- 100 nF – 2 pcs.
- 1 nF – 1 pc.
- 10 µF – 2 pcs.
- 1 µF – 2 pcs.
- 220 uF – 1 pc.
- 100 kOhm – 1 pc.
- 1.6 kOhm – 1 pc.
- 1 kOhm – 1 pc.
- 10 Ohm – 2 pcs.
- 150 Ohm – 1 pc.
- 220 Ohm – 1 pc.
- 390 Ohm – 1 pc.
- 47 kOhm – 2 pcs.
- 62 kOhm – 1 pc.
- 2 MOhm – 1 pc.
- 120 kOhm – 1 pc.
- 470 kOhm – 1 pc.
- Speaker 1 – pcs.
- Diodes 1N4148 – 2 pcs.
- DIP8 sockets – 2 pcs.
- Potentiometer 100 kOhm – 1 pc.
- Potentiometer 10 kOhm – 1 pc.
Printed circuit board
The printed circuit board is made using the LUT method; there is no need to mirror it before printing.(downloads: 1646)
First of all, you need to solder resistors, diodes, then everything else on the board. It is advisable to install the microcircuits in sockets. The wires for connecting the coil, speaker, potentiometer and coil can be soldered directly into the board, but it is more convenient to use screw terminal blocks, then you can connect and disconnect the wires without using a soldering iron.
Making a coil
A few words about the search coil. The best option is to wind 20-25 turns of copper wire with a cross-section of 0.5 mm2 on a round frame with a diameter of about 20 cm. Sensitivity largely depends on the number of turns, so you should first wind more turns, about 30, and then gradually reducing the number of turns , choose a number at which the sensitivity will be maximum. The wires from the board to the coil should not be long, preferably copper and with a cross-section no smaller than the cross-section of the coil wire.
Setting up a metal detector
After assembling the board and winding the coil, the device can be turned on. In the first 5-10 seconds after switching on, various noises and crackles will be heard from the speaker, this is normal. Then, when the operational amplifier enters its operating mode, you need to use the potentiometer to find a mode when individual clicks will be heard from the speaker. When you bring a metal object to the coil, the frequency of clicks will increase significantly, and if you bring the metal into the very center of the coil, the sound will turn into a continuous hum. If the sensitivity is not enough, and changing the number of coil turns does not help, you should try to select the values of resistors R7, R11, changing them up or down. The board must be cleaned of flux; it often causes the metal detector to malfunction. Happy build!