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.
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.
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!
have you solved? Now working?
I haven’t been able to get the metal detector to work yet. Now I have had time to try again and I have visualized the waveform coming out from the arduino. Instead of being perfectly square it has a big negative peak right after the positive one. I also tried another arduino (also disconnected from the rest of the circuit) but the waveform does not change. You can help me?
hello, dear electronics engineer, I found your Spirit Pi circuit and thought I would rebuild it completely. Unfortunately, I would like to have an exact specification of the assembly of the board. I mean which components belong where. Maybe you can show me a photo in detail where I bring exactly which component. Sincerely, Juergen
Hola querido ingeniero electrónico, ¿cómo se flasheó exactamente la placa esp32 con qué cargador de arranque y qué firmware? Pide tu ayuda También estoy dispuesto a enviarte una donación.