Regarding the fluxgate sensor and the gradiometer

[hykj888]

it is important to clarify two distinct concepts resolution and sensitivity. These two parameters are often confused. For fluxgate sensors, the core parameter is resolution, and sensitivity can be improved through operational amplifiers or other means.
Feedback types can be divided into two categories: open-loop and closed-loop. Open-loop fluxgate sensors have the advantage of high resolution but suffer from low linearity consistency. Closed-loop fluxgate sensors, on the other hand, offer precision but have slightly lower resolution.
Among common low-cost fluxgate sensors, theGM-3 is an open-loop type with high sensitivity but slightly worse linearity. This nonlinearity is caused by the nonlinear magnetic permeability of the material under different magnetic field strengths different frequency hysteresis losses. The FLC100 is a closed-loop fluxgate sensor with perfect linearity. The key factor limiting the performance improvement ofgate sensors is Barkhausen noise, which is determined by the magnetic core material. The resolution of the FLC100 fluxgate sensor is 3nT, which is the limit of the performance of a single bar-shaped fluxgate sensor. Some people attempt to improve sensitivity by replacing the magnetic core of the FLC100, which is joke and a clear confusion between sensitivity and resolution. Under certain specific conditions, sensitivity may indeed improve, but that is an incorrect state. Isn't it simpler to add an amplifier use a 16-bit ADC? Another joke is to say what the inductance of the FLC100 magnetic core is. The inductance of this structure significantly under different magnetic field strengths, and different measuring methods and instruments will also put the magnetic core in different states. Therefore, comparing inductance is a meaningless thing.
How we take advantage of each other's strengths and minimize the impact of weaknesses in use? For example, pairing with FGM-3 is a very difficult task that requires a lot sensors to be selected from. This is even more labor-intensive than manufacturing sensors. The paired sensors are expensive and far exceed their value. The simplest method is to ensure the direction of the sensor during use, and it is very effective to use a 16-bit ADC with the FLC100 sensor and add filtering algorithms.
of the things that are most easily overlooked when using fluxgate sensors are power supply and the stability and coaxiality of the mechanical structure. Mechanical vibration is also a major source noise. Regarding the distance between the two sensors in the gradiometer, theoretically speaking, the farther the distance, the higher the resolution. However, the farther the, the more difficult it is to ensure mechanical strength. This requires a balance. Professional gradiometers typically have a distance between the two sensors of 70cm or 10cm.
Regarding 3D software, the communication of Euromag 3D is encrypted, while others are generally plaintext communication. It is easy find the communication format and baud rate. As long as the Bluetooth is set correctly on the MCU side and the data format sent is correct, these 3D software can used. Due to busy work, I rarely visit the forum. If you are interested in in-depth discussion, you can communicate with me through the following methods
Whatsapp：+852 62327564
email:[email protected]
Aliexpress:www.aliexpress.com/store/1104214418

[ivconic]

...Regarding 3D software, the communication of Euromag 3D is encrypted, while others are generally plaintext communication...

Ha, ha, ha!
As I wrote to you in an email a few weeks/months ago; you didn't decrypt anything... because there was no encryption in the version I sent you.
Young man... you haven't listened to me in months, that's why we don't work together anymore.
Last year at this time, you didn't even know what a magnetic sensor was.
And today, look, you are a top expert!
In a previous post on another topic, you even mentioned that you were going to write a book!
Congratulations! I look forward to your progress. When the book goes on sale; please let me know, I will be your customer.

[ivconic]

Your inexperience and poor judgment are clearly visible here.
You are giving yourself a huge anti-advertisement that will only bring you harm.
Instead of obtaining knowledge in a legal way in an honest way; you yourself admit how you "hacked" the software and hardware that I sold you for a very low friendly price.
What does that say about you?
What kind of respect do you expect from other people on the forum if you brag about hacking other people's intellectual work?
Do you expect cooperation with other people on the forum? Do you expect trust from others?
No, you didn't encrypt anything and you have nothing.
You got an old, outdated, "lite" version of software and hardware from me.
No encryption.
That was a test for you, you didn't pass it.

[ivconic]

FGM-3 Nonlinearity, incomplete explanation!
Blaming FGM-3’s nonlinearity solely on permeability and hysteresis glosses over temperature drift and excitation current instability, which are equally critical in open-loop designs.
These are well-documented in literature (e.g., Primdahl 1979).

Gradiometer resolution oversimplification!
"The farther the distance, the higher the resolution" is misleading. Increasing baseline improves gradient resolution but harms common-mode rejection.
In real-world gradiometers, you optimize for noise floor, not just raw spacing.
Your 70cm/10cm examples are arbitrary without context.
Again, your hollow knowledge that you picked up through instant AI chat attempts is clearly visible here.

Barkhausennoise isn’t the only limit!
Focusing solely on Barkhausen noise ignores:
- Preamplifier noise (often dominant in low-field systems).
- Thermal drift (kills offset stability over time).
- Clock jitter in excitation circuits.
- Calling Barkhausen the "key factor" is only true for ideal lab conditions.
And again, it's clear here how stubborn you are and you didn't want to listen to me!
For months I've been telling you to go out into nature and get some basic and very useful experiences away from the laboratory.
You didn't listen to me, as usual!

FLC100’s 3nT "Limit" ... not universal!
The 3nT resolution limit applies to bar cores, not ring-core or thin-film fluxgates (e.g., TDK achieves <1nT).
This is a material/geometry limitation, not a hard law.
Young man, you lack knowledge and practice, but you don't lack impatience!

Power supply stability... really? Where’s the detail?
Mentioning power stability without specifying ripple tolerance or linear vs. switching regulators is hand-waving.
Fluxgates need µV-level supply cleanliness; this isn’t optional.

Euromag 3D "Encryption"!? Vague claim, funny !!!
Does "encrypted" mean AES? Checksums? Proprietary encoding? Without details, this is just FUD. Other software might use binary protocols that aren’t "plaintext" ASCII.
With the help of a serial monitor, you "discovered" a dozen special symbols at the beginning of each data transfer, and you consider that your extraordinary achievement?
Ha, ha, ha!
Did you decipher those symbols, do you know what they mean?
Trust me, you don't want me to write here how those symbols look in translated and understandable language, you will be humiliated if I do!

Conclusion:
You’ve got the basics right (AI you asks about those things is giving you basic rigth answers),
but the oversimplifications and dismissive tone ("joke", "meaningless") and lot of vague claims with holes; undermine credibility.
If your book will look even a little bit like your post... it will be a book to remember!




Fluxgate design is about trade-offs (sensitivity vs. linearity, noise vs. bandwidth), not absolutes.
If you’re going to critique core swaps or inductance, back it up with data or references; otherwise, it’s just opinion.
...

And now is the perfect moment to thank me for another completely free lesson and guidance that I selflessly gave you
(as I have many times in the past months ... and you "thanked" me by "hacking" my intellectual work)


P.S. For a deeper dive, I recommend papers by Ripka or Primdahl on fluxgate noise sources and core material impacts.

[ivconic]

My case of cooperation with you, as well as these few topics and posts that we exchanged in the last few days... not only do not serve your honor and benefit...
but they do irreparable damage on the planetary level when it comes to attempts to cooperate and do business of the "western world" with China.
Because your behavior, avarice and stupidity; they only add fuel to the fire, they confirm old experiences that you should not cooperate with people from China.
Because they always have the same ultimate goal; that they don't pay anything honestly, that everything costs them for free and that they always steal and abuse other people's knowledge and work.
Of course I know it's not like that.
But your performance here on the forum and my experiences with you indicate that it is so.
Young man, you are doing great harm to yourself and the People's Republic of China with your immature and stupid behavior.
Do your superiors know what you do? Should they be notified?
Should the civil service of the People's Republic of China pay attention to your behavior?
And the "business" you do outside of your regular job?

[hykj888]

If you understand, if you have the ability, would you worry about three meals a day? Idiot!

[hykj888]

What else can you do besides going around with stolen goods? The people on the forum all know that you are a fraud, and I'm worried that you willve to death!

[hykj888]

Look carefully, first, I am talking about single strip magnetic cores, flc100 is already the limit of the resolution of the magnetic flux gate of this shape of magnetic core, if you want to improve the performance, you need to change the structure of the magnetic core, adopt two magnetic cores, ring, runway shape have an order of magnitude improvement. Second, theoretically, the longer the baseline, the higher the sensitivity of the gradient meter, which can be easily derived from the formula of magnetic field, and I also said that this is only theoretically. Third, I am saying that the biggest obstacle to the improvement of the performance of the magnetic flux gate sensor is the Barkhaus noise, which is the most difficult to solve. The performance of the sensor I talked about is explained by data, unlike you who only use your clamp to evaluate a sensor

[ivconic]

Is it a Chinese custom to insult people like that?
Do you expect anything good from me after such insults?
Do you think I can't hurt you?
Do you think I can't report you to the authorities of the People's Republic of China for copyright abuse?
At the time of covid, a Chinese contacted me via email and asked me for a couple of projects, but for free, as a gift!??
When I politely replied that I don't give away commercial projects; he replied to me with an email in which it was written:
"May God grant that you die of covid in the most terrible agony!"...
Those are my experiences with the Chinese so far.
I don't think those two bad examples represent the general state of mind of people in China, I hope.
Ever since you started asking me for free things more and more, and I started warning you that everything costs money in this world:
since then you started behaving worse and worse.
Think about everything.
Keep acting like that, it's your public image.
And I will officially contact the authorities of the People's Republic of China regarding the report for copyright abuse.
Luckily; Serbia and China are "steel" friends, so the People's Republic of China has official representations in Serbia for all areas of cooperation.
Be prepared for government officials to visit you soon.

[Abdelmanan]

First of all, I'd like to thank the person who brought a bit of comedy to a serious technical discussion with these random accusations. It certainly added some unintended entertainment value.

As for Mr. hykj888, he is well-known for his professionalism and high moral standards. He doesn’t need to defend himself against accusations that sound more like third-rate science fiction. The man shares his expertise respectfully, and anyone accusing him of theft or hacking might first need to learn the difference between a code file and the pirated movies they seem more familiar with.

It’s clear that some people struggle to accept the presence of those who are more knowledgeable and capable, so they resort to attacks instead of constructive dialogue. It’s a well-known tactic: when the argument is lost, the shouting begins.

Our friend hykj888 has provided valuable insights that many have benefited from. As for those who throw around baseless accusations, perhaps it’s time to upgrade the operating system in their brain—there might be a jealousy virus running unchecked.

In the end, we prefer dealing with people who have both knowledge and integrity, rather than those who only have a keyboard and a thirst for drama.

[ivconic]

[ivconic]

hykj888 with 24 posts: "has contributed so much to the forum community that it is admirable"
and you with 1 post on the forum have all the credibility to write such claims!?
Is this possible?
What a mockery this is!
You are both truly completely credible and worthy of attention and trust, of course!
However, I sincerely take my hat off to you for one thing: you have an unprecedented sense of humor!
I laughed like rarely before!

[Abdelmanan]

Ah, I see we've moved from baseless accusations to full-on theatrical sarcasm bravo! You truly have a flair for dramatic writing; ever considered a career in stand-up comedy?
Let’s break it down: the number of forum posts has suddenly become the gold standard for truth and credibility? Fascinating logic. By that measure, Shakespeare was irrelevant on social media too.

But let’s get serious for a moment hykj888 has earned respect not through post count, but through the quality of his contributions, technical depth, and respectful interactions. Meanwhile, trying to dismiss that with inflated sarcasm only highlights a lack of substance in your argument.

Still, I appreciate your attempt at humor. It’s just a shame it came wrapped in envy and a shaky narrative.

At the end of the day, credibility isn’t measured in posts, but in principles. And from where we stand, it’s pretty clear who’s got them—and who’s just trying to borrow attention.

[ivconic]

Some time ago I clearly warned Carl that the forum is full of trolls, especially trolls from the east.
Forum activity has drastically decreased, there are fewer and fewer constructive ideas and topics... but that's why there are more and more trolls from all sides.
Forum activity has declined, unfortunately, due to the very bad political and economic situation in the world.
People have withdrawn into themselves, they look primarily at elementary things and have less and less enthusiasm for hobbies.
I sincerely hope that the situation in the world will calm down and improve and that we will all return to normal life.
But I'm afraid that won't happen so soon.
On the other hand, the increase in the number of trolls only testifies to the very difficult economic situation that has affected most of the planet.
Now everyone is looking for some irrational straw of salvation in anything.
Unfortunately for all of us (both trolls and regular productive members); the situation with metal detectors is also dramatic, it is a big crisis.
Almost everything has already been said and done on those topics, which could be done with the current technology.
Metal detectors are getting harder and harder to live with/from.
As old, experienced and hardened in these stories; I have a well-intentioned piece of advice for all the trolls on the forum:
my dears, the time of famine is coming, it is wiser for you to turn to agriculture, animal husbandry, food production.
Because hard times are coming!
...
Ah, my apologies Mr. Shakespeare! You are right! 24 posts can of course be more valuable and with greater weight than even 1000 empty ones.
There is only one problem in this case:
last year, around this time, hykj888 didn't even know what a fluxgate sensor was.
And then he met me and received all the necessary information from me, as well as several months of study, training and counseling.
He also didn't know many other things, which he later got from me and through that he learned something.
hykj888 is still a progressive young man who has some good skills and has the ability to think progressive.
If it were not so; I would not cooperate with him for almost a year.
The problem arose at the moment when appetites grew.
They say "money corrupts people"... never was that truer than in the case of hykj888 and his slow progress, which I followed and helped month after month.
hykj888 will one day be a highly educated and capable engineer with a lot of knowledge, I have no doubt about that.
Unfortunately... the human side, ethics and morals are not his strong point.
And without that; everything else is worthless to him.
...
Mr. Shakespeare... I apologize for taking so much liberty in answering you and explaining some things that you pretend you don't know.
Your 2 nonsensical posts are certainly worth much more, hats off to you!

[ivconic]

Ok, so far I've been writing empty and stupid posts, now it's time to write at least one post that will have Shakespearean weight!

"Behold yon man with wand and frantic stare,
Who digs for treasure ‘neath the county fair.
‘A sovereign’s hoard!’ he cries with face aglow,
Then pulls a rusted nail—his mightiest foe!"

"‘I’ll find the gold!’ he swears with metal stick,
And digs a hole so deep it makes him sick.
The cops arrive—‘Why sir, this land’s not thine!’
‘But hark!’ he weeps, ‘I’ve found… a 1999 dime!’"

"May all his digs find naught but trash and woe,
His coil snap off, his batteries run low.
And when he brags of skills he's never shown,
May every beep prove just another stone!"