IDX-PRO+VDI

[Uiliam950]

ok but I didn't understand this measurement of the null point it must be found the null point with the coils connected to the pcb and with the pcb connected to the 12v battery?
and I have to measure the coils with the capacitors or without the capacitors

[dgm]

The coil must be connected to the metal detector once turned on, the RX coil must be blocked and the TX must be superimposed as in the photo sent by you, the measuring instrument must be connected on the two RX wires, and by moving the tx slowly check the voltage in alternating current as low as possible.
Once a voltage of 8 - 15 millivolts has been reached, also block the TX coil.
The coil must have the capacitors connected and the idx turned on.

[Uiliam950]

The coil must be connected to the metal detector once turned on, the RX coil must be blocked and the TX must be superimposed as in the photo sent by you, the measuring instrument must be connected on the two RX wires, and by moving the tx slowly check the voltage in alternating current as low as possible.
Once a voltage of 8 - 15 millivolts has been reached, also block the TX coil.
The coil must have the capacitors connected and the idx turned on.

good night I adjusted my coil at the null point it is at 8 millivolts it has improved the sensitivity a little bit it is taking a cell phone at about 20 centimeters but it still continued with the crackling sound like it was passing some object on the coil

[Uiliam950]

I noticed that removing the U4 lm393 integrated circuit from the board it stopped bibaring and it worked normally, but with little sensitivity
picking up a cell phone from 20 centimeters I have already put another new lm 393 in its place, but when I put it on the sound starts to crackle again

[dgm]

Hi good morning, I think it is a problem in the metal detector you have assembled, in my experience before soldering the components on the pcb you have to check them with a tool one by one both resistors and capacitors, just a different capacity or resistance can give problems. Now check again all the components you have installed, even the potentiometers that regulate the GB, the TH, the Sens and Discr .. One thing you didn't say the problem you have does it only in all metals or in discrimination?

[Uiliam950]

I think I put this capacitor wrong in the picture it shows 22 n this space means 220 n I think
the correct capacitor is 22n

[Uiliam950]

what is the function of the 10k VR3 on the board

[Uiliam950]

Hi good morning, I think it is a problem in the metal detector you have assembled, in my experience before soldering the components on the pcb you have to check them with a tool one by one both resistors and capacitors, just a different capacity or resistance can give problems. Now check again all the components you have installed, even the potentiometers that regulate the GB, the TH, the Sens and Discr .. One thing you didn't say the problem you have does it only in all metals or in discrimination?

the problem is with all metals because I can't get any kind of adjustment

[Uiliam950]

good morning I found 3 more wrong capacitors, these 3 marked in the photo I put 1nf and the project is 1uf I think this is the biggest mistake

[surfdetector]

[ATTACH]56175[/ATTACH]
good morning I found 3 more wrong capacitors, these 3 marked in the photo I put 1nf and the project is 1uf I think this is the biggest mistake

Can you post a copy of the schematic that you are using?

[Uiliam950]

[Uiliam950]

C8
C10
C16
they are 1uf capacitors and at the time of assembly I got confused and put 1nf capacitors

[Emersonpaz]

After replacing the capacitors, is the board working again?

[Uiliam950]

I'm waiting for the order for the capacitors to arrive

[bgs]

Whites Classic 3.Two tons of discrimination. It's easy. The three channels work together.