New version (Beta):
In this version this metal detector works with a smartphone or without a smartphone with the possibility of adding an LCD screen. Now Spirit Pi is more stable and reaches more depth. The diagram and the PCB can be found below, also in the file you will download will be gerber file in case someone wants to order the PCB on the JLCPCB page. JLCPCB is a page where we can order the PCBs we want for a very low price, we just have to upload gerber file of the circuit and that’s it.
News:
Now in this detector we have 3 buttons: “+”, “-“, and the “M” menu. With these buttons we can adjust the pulse width, sensitivity and frequency. Instead of the TL072 amplifiers we will use NE5532. The micro controller will use an Arduino nano. The coil is still 25 turns with 0.5 mm wire and the radius 20 cm.
Components:
The components I usually buy on Aliexpress for the low price. In this way we can make a good metal detector and spend little money. Below I will leave the links where you can buy these components to make this metal detector!
Hello Sergey,
I have a bunch of TLV2375IN Quad-Amp laying around and would to use one to build a Spirit Pro, because I don’t have any NE5532 at hand. The TLV is noisier and a bit slower (2.4 V/us) and has a smaller bandwidth, 3 MHz. More critically, in split supply it accepts a maximum of +/- 8 Vdc.
Do you believe it can be used to build a Spirit Pro 4 without serious performance degradation?
Thanks.
Hello Gustavo! It is difficult to say without to see the op-amp under the oscilloscope. It will work but maybe you will need to adjust some values of resistance. You can try if you have some problem ask me i try to help you. Make sure the pinse in your op amp is the same like ne5532
Hello Sergey,
Thanks by your answer. The whole problem os that I don’t have a scope. I was plannig to use the smartphone with a custom board as a simple scope (the SmartScope app is a great one) but, somehow, I fried the phone’s ADC when trying to make the RFinder circuit work (it didn’t work with BC558, A733P, C945P. I Googled about the somewhat unusual Peltz oscillator topology used in the RFinder circuit, but it didn’t help).
I plan to make a simple scope using an Uno/nano board, but I guess it may not be enough for a decent circuit analysis.
Anyway, I will build a Spirit PI next month (awaiting Aliexpress delivery…) and, if time allows, try the Pro 4 version. Pinout is easy to solve, I redraw every schematic in CAD before a try to ensure pinouts and PCB layout are appropriate before heating the soldering iron.
I’ll report the success (or failure) for you when done, just as a feedback. If things go really well, I plan to make an all-smd version just to make thinks really, really portable.
AMIGO PODRIAS COLOCARLE LA OPCION A SPIRIT PI 4 QUE TENGA DESCRIMINACION DE MATALES PARA DIFERENCIAR EL ORO DEL HIERRO O DE OTRO METAL, TE AGRADECERIA SI PUDIERAS HACERLO PARA EL DETECTOR.GRACIA Y TE FELICITO POR EL PROYECTO.
A simple algorithm using machine learning can be developed to discriminate between many metals, including a rough estimation of size and depth. What is needed is a reliable and stable circuit, the full capture of the pulse decay and a lot of samples taken from real metals in real terrain. If data is available, will be a pleasure for me to run the methods and implement the algorithm in an Arduino board.
Sergey,
Other very useful, and easy to implement, option for the metal detector is a flashlight. Using few white LEDs near the coil should work without much (if any) interference, and a single tactile switch can be used to turn the light On, Off, or to dim the light when continuously pressed. A double clink event resets the light to maximum power. Easy to implement with already available libraries for Arduino.
Hi,
Im from YouTube about wrong layout, will do the black and white instead for prototype and wait the parts arrived. Thanks
Hi! So you didn’t get work the gerber file ?
Hi .. good morning bro..
I just seen many time your videos and webpage.. by profession i am trasure hunter in india.
I used many devices. Now
Try to make this spirit pi 4 ..
Hope its working …
Because i am not exper in electronics..
Thanks
Say hi to. Your cute team
Thank you!
Hi.. how many AH battery use for this??
Hello, i am using 11v li -po bettery 2200mAh
Good day
Can you explain the control pulse
Thank you
yes of course!
Hi Neco
I want build the Spirit Pi in ESP32 Version, but the App is not working at my Smartphone. The Smartphone is an LG G5 with Android 8.0.0
Have you an Idea wath is the Problem.
best regards
Roland
I will test it and fix ! i think is because the android version 8.0.0
Hi Neco, great job. I want build Spirit PI 4 Pro A.
A quick question for you :
based on schematics and video R3 is a trimmer and R14 is a potentiometer.
Am I coorect ?
can you tell how to tune R3 ?
Several resistors have a * what does it mean ?! Several resistors (I don’t know if also other components) have different values in the schematic compared with the BOM. What are the right values ?
thank you
Marco
Hi Neco,
where are you come from?
kind regards
bernte__one
Hello i am from Russia but now i am live in Spain
Hello neco your project is very good and interesting l want to build this project. can you help me about hex file for arduino? Tanks
There is only arduino sketch i am not use hex file.Thank you
hey bro ..
can you share the shcematic please?
Hi! it below the project in the same page, you can download it
could you post a flow chart for the whole code
What do you mean?
Hi Sergey
This does not work for me.
What is the inductance of the coil?
Thanks
300 -> 400uH
Hi Sergey
Working fine now.
Discovered that Sens is default is 255 but needs to be around 10 to be effective>
Hi Sergey
Could you email me with details of the design/CAD package you use please.
Thanks
Hi Neco,
I am having difficulty with the device. The balancing time is very short and the ring is not detecting anything. Pl help.
I have the exact same issue. Here you able to make it to work ?
Olá NECO. Montei o seu projeto. Ficou muito bom. Funciona perfeitamente. Fiz pequenas modificações devido aos componentes que utilizei. Parabéns pelo seu trabalho. Tenho somente uma dúvida: como faço para mostrar o nível da bateria no display?
can i use TL072 amplifier because i don’t have NE5532 , is that gonna affect the depth , thank you
is there any equivalent to NE5532 because i cant find it .
can i use NE 555 or TL072
Hallo Sergey ,
Beautiful project, I have also started it and have everything ready only it is impossible for me to adjust the voltage on pin 1 of the NE5532 to 8 Volt, whatever setting I do the voltage on pin 1 always remains 11.35v, at I also measure the voltage on pin 3 and it varies nicely between 2 and 10 volts, I have already exchanged the NE5532 with 2 other copies but the result is always the same, maybe you know what to do? Thanks Alex Jacobs Belgium
No coil and no arduino connected. Then you can set pin 1 to 8v
Hi Sergey,
A great project, I have rebuilt it in the meantime, but I cannot adjust the voltage on pin 1 of the NE5532 to 8v, regardless of the position of the trimpot, the voltage remains at 11.35v. I have already replaced the Ne5532 with 2 other copies but without success, you have some idea what is going on. Thanks Alex Jacobs Belgium
Pcb Spirit PI 4 Pro AThe bottom is based on the Arduino nano oresp32
Hi neco
Is the PDF file for the pcb board found in the version Spirit PI 4 Pro A does it support esp32 or ardeno nano
Hi
What is the best version Arduino nano or esp32
Hi Neco,
I would like to make your Spirit Pi 4 pro but I don’t find gerber files for the controls pcb (3 buttons). Did you integrate this new function on main PCB ?
Hello Sir
Spirit PI 4 Pro A is very nice project. I want to download schematic but I’m facing update problem in 2nd page.If possible please help me.
Hello Sergey,
Interesting work. Do you have a system or a way to use coils with 2 or 3 windings rather than 1? I am more for looking to build something that works very well without looking at the price tag…. Would you be able to have something built like a hi end PI metal detector? What about discrimination or metal indication?
Thanks
Frederic
Hello Sir
I am having problem in 2nd page of schematic in PI4
Hello Neco , you did a great job . I am buildind the lcd version , can you explain why you drive the signal via Q1 and not directly to SU2 ? Could you give some light over the balancing process ?
Best regards
etienne
hello neco
i have a problem
i follow u step by step but when turn it on stay on balancing…
i adjust the resistor variable and nothing change
plz help me
hello neco
i made this project but doesn work with me like yours
its stay at balancing when turn it on
i adjust the resisitor variabl R16 and nothing change
but where is the position L1-2 of resistor 1M on the pcb ???
i think my spirit pi doesnt detect the coil …
can you help me plz ?
hello, did you see my video about colibration?
yes. i watch it. i made it 3 times in 3 pcb . but same problem
have you solved? Now working?
I would like to speak with you regarding making some high end PI detector if that is possible. Do you have an email ?
Thanks
Frederic`
Hi ,
I have a problem ,
I follow it step by step but when you turn it on,
Keep balancing … I adjust the variable resistor (R16 100k) and nothing changes please
Help me out
does not work .. no qay to adjust 8 v in bin one of ic
i made it three times .. no way to adjust clebration of first pin to 8 volt .
hi sir
i did your project ..
but i can not adjust 8 volts on first pin of ne 5535 can you help ?
hi, this is not ne5535 this is 5532
buenas tardes saludos por sus proyectos. el único problema es que nadie ha echo andar al momento me parece. seria interesante que suba el eskes del Arduino corregido como lo prueba en el video. esperamos su pronta respuesta gracias. cambie el tono de detección de objetos de metal a un sonido pueda ser continuo.de esa manera la búsqueda seria mas positivo si será como hiso se pasara uno al buscar por la respuesta no es muy rápida.
hola, ya hice correcciones en el ultimo video me al escribir los componentes. Si, hace falta mejorar la velocidad de respuesta
Hello, great works, thank you very much, i want to understand the Android part, where to find the source please ? ( A GitHub url )
Greeting
I would like to buy a metal detector.
How and where to order it and how much it costs.
Kisic Ljubomir
Belgrade Serbia
G’day Neco.
Can this unit be powered by a 9v battery. If so do I need to make changes.(Can I use the spirit pi without using the smart phone).
hi, yes you can use it without smartphone
What is its depth of detecting? i really want to build one and i hope it performs as good as the premade boards available in the market.
Depth is 25 cm small coin 1 cm diameter. or 1 m 30cm diameter objects with coil 19cm diameter
hello neco
im still have a problem with detecting coil
Can you determine the resistance value R16 after calibration
And if you can specify the inductance of the coil
Hi Neco,
Great project – thanks very much for giving so much detail. I’m putting it together now. I’m a semi-retired software engineer, so I’m looking forward to using a rotary encoder and a simple menu system for the settings, though the Arduino interface is a very nice touch 🙂
I tried the coil driver circuit at 12VDC supply and after a few minutes the MOSFET seems to get quite hot (maybe 45C) is this ok ? (Coil is 20T of 0.5mm copper 200mm dia)
Cheers,
Geoff.
Hi Sergei, I’m Chandra from Indonesia … I saw your file uploaded on November 28, 2019. While in your February 2020 video entitled “Home Made Arduino Metal Detector Part I,” there is still an error by adding a 47nf yellow capacitor. where is the final scheme after all the mistakes have been corrected?
Thank you brothers
Hi Sergei,
I am Zak from Greece, Very interesting build and project, thank you!
I just finished simulating it in Proteus and it works very well. I have one question though, when you adjust the value of R3, you said we need to have 8V on Pin 1 of U3, you mean 8V DC or AC?
Thanks again
Hallo my friend. Can you make android program same with spirit pi 4 for me. And hoh much the cost for built it. My email eswepe11@gmail.com whatsapp +6282130213232
Dear Sergey,
I have realized your project spirit pi but unfortunately it doesn’t work. I need your opinion on oscilloscope ‘s measure to understand where my board failed, can you check here: https://com3x.fr/spirit-pi/
regards
Pascal
Hi Sergey,
I built the detector and followed your directions about the settings but unfortunately it doesn’t work.
I checked the signals on the oscilloscope and it seems that the sampling CP2 is not triggering at the right moment.
At the output of the preamp i have the expected signal, but things are not going well after that.
Do you have an idea why?
Can you provide pictures of how the signals should look like so that I can have some guidance.
Thank you in advance.
Abderrazek
hi
Capacitors several watts?
hello Sergey
I have a problem
I followed you step by step but when turn it on it stays on balancing…
I adjust the resistor variable and nothing changes
May I ask you some help? Thanks!