PiTone-v2-by-Eddy71 Has anyone on here built this ?

[David_1]

https://www.seeedstudio.com/Metal-Detector-PiTone-v2-by-Eddy71-g-1226359

no clue why I have taken a liking to it, but I am just starting to draw the PCB
David

[bernte_one]

why you draw the pcb? there is a a layout you can use already, Eddy71 on forum

[David_1]

why you draw the pcb? there is a a layout you can use already, Eddy71 on forum

Drawing a pcb for me is easy, his PCB has a documented error, so I do not need that and I do not want the motor vibrator function either.
I have code so a new pcb seems best

[David_1]

no clue how to make them appear in post but there is my pcb, being made as we read this by jlspcb, in a week or so I will let you know what arrives

[David_1]

HEY this looks better

[David_1]

am I right in thinking these are very similar but with different micros ?

[David_1]

I like things drawn a little different, so I redrew Eddies drawing, its almost Identical your thoughts ?

[Eddy71]

We'll soon find out if this is right. After turning on the device

[bernte_one]

can someone translate this comment over the damping resitor array R3,R4,R7 to R18?
instead of placing parallel 3x1k it it also legit to use single 1-3W 330R resistor, or a 5W wire pot for tuning the damping resistor
but what is the relationship to R18?

[David_1]

can someone translate this comment over the damping resitor array R3,R4,R7 to R18?
instead of placing parallel 3x1k it it also legit to use single 1-3W 330R resistor, or a 5W wire pot for tuning the damping resistor
but what is the relationship to R18?

The words seem to say coil settings ?

[Eddy71]

The resistance of R3,R4,R7 and R18 depends on the inductance and parasitic capacitance of the search coil.
Three slots on the board R3,R4,R7 for easy selection of the resistance. First we use a variable resistor to determine the required damping, and then we solder 2-3 resistors with the same total resistance.

R18, P1 and C6 form an integrating circuit.
The form of the voltage drop on it should be equivalent to the form of the induction voltage drop on the search coil. Then the sensitivity of the device is maximum.

[Eddy71]

I also forgot to write. When repeating the detector the most dangerous part of the project is the purchase of TL072 and IRF740.
Many times I bought them on Aliexpress and they always sent a fake one.

[bernte_one]

I also forgot to write. When repeating the detector the most dangerous part of the project is the purchase of TL072 and IRF740.
Many times I bought them on Aliexpress and they always sent a fake one.

maybe you can try TME.eu next time

and thanks for explanation

[Eddy71]

Found it in old diary entries

[David_1]

My pcb that I am drawing now is 33 x 36mm , the ones stuck in China are a little bigger ... I think that faa thing that grounded planes. has caused the delay