SBG- slow motion metal detector

[ivconic]

If I continue the story in this manner; maybe i will provoke some good engineers here on the forum.
But there is an old Serbian saying: "not everything that flies is eaten".
In this case; anything that looks really good on the design table or in the simulator; it does not necessarily prove good in real conditions on some soils.
Here, I first have in mind the progress of science and technology and the very arrogant certainty of some top engineers, from large companies, to whom their designs in ideal mathematical conditions seem perfect.
In real life, such "perfect" designs here on my local soils mostly turn out to be little babies without clean diapers!
Specifically, to be even more direct; here I am thinking first of Minelab Manticore and XP Deus 2. Without ten packs of "diapers" I would never go out on serious quests with them again.

[ivconic]

Yes, I am 80 km from the border. 120 km to Vidin, I went there often to the flea market!
A good analog design will always be relevant if it provides something interesting.
Feel free to believe me; there is hardly a brand and model of metal detector that is worthy of attention; without having passed through my hands until now.
I've been at this for 40 years.
The new digital "MF" detectors are ok, but like many before them they have a lot of flaws.
Flaws are not expressed in the same way everywhere on the planet.
I've been searching all my life for a detector that will give more quality to my soils that I have around me.
That's why whenever I see something interesting; I am very excited to try it on my soils.

[scs-bg]

You are absolutely right. It is very difficult to learn a language in its technical form. Today, after so many years, I saw where Sokobanja is. I saw that you are close to us. We are very close people with a common past. Unfortunately, often tragic. Bulgarians love their neighbors despite this. I have a health problem. I would make a new circuit board. I did not expect that this construction would arouse much interest. I wish you success

[GeoMax]

Yes, the English language does not match 100% with the way of thinking of the Slavs.
I learned that living in Greece, I learned the Greek language much easier and faster, just because throughout history we have been mixed a lot and were close,
even though the Greek language is 100x "harder" than English, but actually it is not.
Because the mentality is similar and the way of thinking and assembling thoughts into sentences is quite similar between Serbs and Greeks.
And the Bulgarian language is of a small difference from the Serbian language, and I quite understand Bulgarian.
If I lived in Bulgaria; I think I would learn that language perfectly in a couple of months.
Language has direct connections with the brain and way of thinking. Few people "deeply" think about it, except professional philologists and translators.
Literal translation from word to word often does not give accurate results and often completely changes the meaning of the sentence and thought.
And here we don't just use plain English, but "technical" language is involved, which is specific and somewhat more difficult than ordinary everyday English.
But I only recently discovered the biggest mental differences in converting thoughts into language, a couple of years ago, when I started working with a colleague from China.
Despite AI and despite highly advanced online translators; very often I have to change the order of words in a sentence several times in order to get a meaningful message that
I want to send to my colleague from China... and vice versa.
At first, for the first couple of weeks, it was hilarious!
We didn't understand anything correct each other! We often "offended" each other fiercely! Ahahahahahaha!
It should have taken at least a month for both of us to realize that the translator was a big obstacle between us!
And then it became clear that it is a matter of mentality and how the brain works.
This is a long post, off topic, but very interesting to mention.
Maybe my posts are so long and tedious sometimes; because I realized that many will not understand the messages properly; if I don't write a small "novel" in the post,
with many details and explanations.
This is not necessary for English-speaking colleagues, they understand "Tarzan language" very easily.
But this is still an international forum, many people look at these topics and I mainly go into detail for them.
An interesting little story about languages and the way the brain works...

Hi Ivconic.

That is true. Not everything one says in English is always understood exactly as intended. Here is something that happened to me many years ago in the Philippines. I had issued a work instruction, asking that it be completed "as soon as possible." However, the Filipinos understood this somewhat differently than I had envisioned. They interpreted the instruction—"as soon as possible"—in the following way: if it wasn't "possible" for them to do it, then the work wouldn't get done "soon" either. Furthermore—regarding multiple instructions given in a single sentence, which is normal for us Germans—usually only the first instruction was carried out, while the others were ignored. It took me quite some time to grasp how others interpret "English."

[ivconic]

Yes, I will look at the pcb design in the next period.
I have a nice box from Bulgaria, I think it is a type box for "Golden Mask".
I'm just measuring the internal dimensions, to see how big the pcb needs to be.
The dimensions are not large, so drawing the pcb will be a little more complicated.
I will have to give up my favorite dimensions of 7.5mm for resistors and diodes.
I will use 2.5mm for both resistors and diodes and maybe 5mm in some places, where the situation allows.



Here is the Sprint Layout template for the pcb that fits into this box:

[ivconic]

Yes, the English language does not match 100% with the way of thinking of the Slavs.
I learned that living in Greece, I learned the Greek language much easier and faster, just because throughout history we have been mixed a lot and were close,
even though the Greek language is 100x "harder" than English, but actually it is not.
Because the mentality is similar and the way of thinking and assembling thoughts into sentences is quite similar between Serbs and Greeks.
And the Bulgarian language is of a small difference from the Serbian language, and I quite understand Bulgarian.
If I lived in Bulgaria; I think I would learn that language perfectly in a couple of months.
Language has direct connections with the brain and way of thinking. Few people "deeply" think about it, except professional philologists and translators.
Literal translation from word to word often does not give accurate results and often completely changes the meaning of the sentence and thought.
And here we don't just use plain English, but "technical" language is involved, which is specific and somewhat more difficult than ordinary everyday English.
But I only recently discovered the biggest mental differences in converting thoughts into language, a couple of years ago, when I started working with a colleague from China.
Despite AI and despite highly advanced online translators; very often I have to change the order of words in a sentence several times in order to get a meaningful message that
I want to send to my colleague from China... and vice versa.
At first, for the first couple of weeks, it was hilarious!
We didn't understand anything correct each other! We often "offended" each other fiercely! Ahahahahahaha!
It should have taken at least a month for both of us to realize that the translator was a big obstacle between us!
And then it became clear that it is a matter of mentality and how the brain works.
This is a long post, off topic, but very interesting to mention.
Maybe my posts are so long and tedious sometimes; because I realized that many will not understand the messages properly; if I don't write a small "novel" in the post,
with many details and explanations.
This is not necessary for English-speaking colleagues, they understand "Tarzan language" very easily.
But this is still an international forum, many people look at these topics and I mainly go into detail for them.
An interesting little story about languages and the way the brain works...

[scs-bg]

Well done, you are very persistent. You will get a very good result if you completely change the board according to the 2026 scheme. With a stabilizer integrated circuit

[scs-bg]

We live in the Balkans, we are Slavs and we can't understand each other, maybe because I don't know English well, I studied German.

[scs-bg]

This schematic, which is hand-drawn, is a schematic of the board you're working with. It was an experimental board. I wanted to help you. But the design underwent changes that you see on the 2026 schematic.

[ivconic]

"...I think you are working on this board in vain..."
No, it is separate hobby for me, to "brainstorm" the sketches.
Now I get it right, thanks for clarifying.
The most proper is the neat schematic you posted earlier ("2026") , but with only one small correction; the 470nF goes to minus instead the ground.
If is that so; than new pcb must be drawn.
Another brainstorm! Fun!

[scs-bg]

This is the schematic of this board. Many things are different.

[scs-bg]

A separate diode limiter is needed at the input of the TL061 to prevent leakage currents in the control of the PN4393. Without the diodes D2 and D3 as on the board it also works. But not as well.When connecting the input of the TL 061 directly to the output of the operational amplifier without a limiter, a trigger effect occurs. So this is what works best.

[scs-bg]

Ivkonic correctly noticed that the 470nF C7 capacitor in the generator is connected to minus. I made a mistake when drawing the circuit with the program.

[scs-bg]

The board also includes circuits for compensation of the received signal, which turned out to be unnecessary. However, many beginners will have a hard time dealing with this. Do what you see on the diagram and you will be satisfied. If you do something different, you will get many related problems.

[scs-bg]

You need to know that the circuit had a small drift of the discriminator when the stabilizer was transistor. With an integrated one there is no such problem. The circuit has also been tested with DD coils with excellent results. There is a problem when working with coils with small inductance, for example omega and coplanar. Then changes are needed in the generator.