Really sensitive pinpointer for grain size objects

[ivconic]

Hi ivconic,
We are neighbors - yes I'm Bulgarian. And you are real Serbian - with strong feelings!
First, thank you for good words for this project. Inside have not nothing new as schematic. I just picked up very carefully every component.
Your drawing of schematic is more readable. In my variant, I put many additional information for make more easy the repetition from DIY people.
It is important that the resistors around the coil have to be as 3pcs in series - the peek voltage is appr. 1000V. Variant with one high voltage resistor is inconvenient - too expensive or too big size of the resistors.
In your schematic you dropped module for battery low indication (yes it's optional).
LED diode in the input of LM337LZ is for "Power on" indication only.
Now, I prepare final versions of detailed BILL OF MATERIALS and sketch with PCB layout and component's placings.

Yes, all of that is true. It is missing and I will correct it and add it. I only wanted to draw the essential part for the first time.
Thank you for adding more files. The most important would be with the layout of the components on the pcb file.
I understand about the LED, but I don't understand what voltage you apply to the "In" of the LM337?

[Detectorist#1]

Voltage drop on green LEDs at current of 5mA is appr. 2V. The voltage on the input of LM337LZ is Vbat-2V. New alkaline 6F22 battery have 9.5V (9.5-2=7.5V input voltage).
"Battery low" module acts at 7.5V battery voltage. Minimal input voltage on the LM337LZ is 7.5-2=5.5V.

[Detectorist#1]

BILL OF MATERIALS for revision C of schematic is ready

[Detectorist#1]

BILL OF MATERIALS for revision D of schematic is ready

[ivconic]

Nice, but you still missing the components layout.
Gerbers when opened; only pcb without components layout, pdfs too.

[Detectorist#1]

The files with components layout will be ready tomorrow, I hope.

[ivconic]

[Detectorist#1]

This is the file for PCB assembly of rev.C of schematic

[pito]

And here is a 1.5 mm steel ball
https://www.youtube.com/shorts/vUPJmrlSTlg

[Detectorist#1]

Hi Pito,
According this video, remarkable change in the picture happens appr. at 1/2 inch distance.
My pinpointer also reacts on 0.5 grain target at 1/2 inch distance. The same result.
Thank you for the video.

[ivconic]

[ivconic]

So much complication over nothing.
The software and methods you use are impractical.
"Thousands" of files with incomplete information.
Unprecedented boredom to put it all together in some logical whole.
I suggest you start using Sprint Layout to avoid all this boredom.

[Detectorist#1]

Hi Ivconic,
Thank you for your serious help!
My force is in hardware, not in software.
But the aim of this forum is - with our common efforts to achieve results in this good hobby!

[ivconic]

Hi Ivconic,
Thank you for your serious help!
My force is in hardware, not in software.
But the aim of this forum is - with our common efforts to achieve results in this good hobby!

I agree.
Would be nice if you can record a short video demonstration of the working device.
And also would be nice if other participants on topic give concrete suggestions about some improvements.

[Detectorist#1]

I agree with you completely.
I will try to make short video - this will be my first attempt in this area.
I will agree with you that will be nice if other participants will be involved with some suggestions for improvements.
Carl gives to me suggestion to change input safety resistor from 200 oHm to 10K and to change repetition rate from 50ppm to 2500ppm and to use "direct sampling" but I don't know what is this.