Pulse Star II (first analog version)

[algan]

Hello, colleagues, is there a diagram of how the main board of the Pulse Star 2 is connected to the discrimination board? Thank you.

[Ssqqar12]

ebay

[roshik]

Has anyone bought this metal detector from the AliExpress store? Is the quality good?

[roshik]

How are you my friends?

I bought this Plus Star 2 board and I don't know how to connect the switches. Is there a drawing of the switches so that they are clear on how to connect them?

Hi
If possible please upload a picture of the back side board.
Thank you

[jstcq.com]

Plus Star 2

[Ssqqar12]

How are you my friends?

I bought this Plus Star 2 board and I don't know how to connect the switches. Is there a drawing of the switches so that they are clear on how to connect them?

[Orbit]

Here are the photos of the Pulse Star 2 Pro. It can be seen that it has two processors these days since I repaired it and tested its depth. On the way, I will see the pulse width and frequency and other parameters.

[Orbit]

I can't see the Gerber files. I checked the Layout 6 file and some values have changed; for example, R from 200k is now 220k.
The 1 ohm resistor of the IRF630 power supply is now 10 ohms.
I installed 10 ohms on my board and haven't noticed any performance degradation with air testing. There has been a slight decrease in current draw and an improvement in the power supply ripple.

Hi Jose, there is no particular improvement, but these are real values! It's not 1r, but 10r, 200k is 220k and in some places the capacitors are 82nf not 100nf! 100nf was put because of easier procurement here in Serbia. So basically there won't be any big improvement in range!These are those original component values! And if there is no gerber file, then I accidentally sent something when I put it in the zip.. I will post it in the next days, although it can be done from Sprint so that everyone can export gerber..

[Jose]

I can't see the Gerber files. I checked the Layout 6 file and some values have changed; for example, R from 200k is now 220k.
The 1 ohm resistor of the IRF630 power supply is now 10 ohms.
I installed 10 ohms on my board and haven't noticed any performance degradation with air testing. There has been a slight decrease in current draw and an improvement in the power supply ripple.

[Orbit]

A slightly improved drawing, now the corners of the lines are almost 100% of the original drawing! Gerber file saved for creation..

[Jose]

Hello Algan, I don't have a 3MHz crystal to test, it's hard to find here where I live. But I would like to experiment with higher frequencies. I believe that the pulse widths do not depend on the frequency; the module I bought has a TX of 125us, the samples are 300us and this is due to the 1.2nF capacitor. What I know for sure is that if the capacitor is reduced, the duration of the pulses is also reduced or vice versa, and the same happens with the 82K and 200K resistors, but independently.

[algan]

Yes, Jose, we can experiment. My suggestion for an experiment is, for example, without changing the resistors you mentioned, but by changing only the quartz instead of 2.5 MHz, to test at 3 MHz. Then the frequency will increase, maybe to 700 hertz, and with that the pulse width will also increase, but I can't say by how much, maybe between 110 us or 120 us, I don't know exactly, I haven't done it, but I can't say whether it will affect the depth.

[Jose]

Hi Orbita, I don't doubt what you're saying. I appreciate your work; thanks to them and other forum members, we now have all the information about the PS2.
Algan, my coil is 45 cm in diameter and has an inductance of 660 uH. I tried a 470 uH coil and an 880 uH coil, but they didn't work well.
It's essential to correctly adjust the damping resistance.
The distance to the 475 cm³ soda can is 100 to 110 cm. There's a slight improvement when increasing the transmit pulse width to 200 us, but I don't know if it's really worth it, because it also increases the consumption, from 105 to 185 mA.
The good thing is that we can experiment with the TX width without affecting the other parameters.

[algan]

I've been running some tests. The 200k and 82k resistors and the 1.2nF capacitor near the 4022 IC set the initial and final sampling times, as well as the transmission pulse width. They also influence the delay.
I replaced the 82k resistor with a 130k resistor, and the transmission pulse width was adjusted to 200us without affecting the other parameters.
Current consumption increased from 105mA to 185mA.
Air tests show an improvement in detection distance; this remains to be tested in the field.

Hi Jose, can you tell me how your test with air on a Coca-Cola can with your antenna is, but tell me what size is your antenna? I will try changing the resistor and test if it affects the depth.

[Orbit]

Hi Jose, believe it or not, I have a project from before, I don't remember exactly, but about ten years and maybe more during that time I made one device for myself, one I gave as a gift and another that I also gave to the man who gave me the first module, so a total of 3 devices. As I may be here on this thread or somewhere on another thread I wanted to respect the author and I didn't want to sell the whole project was just put aside. I was asked by many, among others, and some from Bulgaria to be involved in this topic, I simply did not want to out of respect for the author.. You know how it went on!!! So I paid almost no attention to this project for many years, I am presenting what I wrote down and tried a long time ago, but I was not occupied much with this project.Now everything is here that the hobbyists wanted, and I believe also the producers from Bulgaria who supposedly invent projects from their heads without ever having attended geotech in their life.