XP something ... something... WTF?

[ivconic]

And finally, a direct field experience that I noticed while working with Deus 2, while at the same time a colleague with Manticore was walking next to me.
In case Deus 2 (same as Deus 1, because I have eliptical HF coil for Deus 1 too) uses a white HF coil; Mantcore has no chance.
To achieve the same performance; the Manticore user has to "boost" the settings to the point where the Manticore turns into a very loud church organ!
And that's not my one-day experience. I'm talking here about 20 outings on various fields in the course of a couple of months.
In case Deus (1 or 2) use "black" coils, it's a dead race, two church organs, totally out of tune, playing loud to unbearable limits.

[ivconic]

If I were the president of France, what was his name ... a "Maricon" ?
I would change the constitution of France and directly forbid XP to produce "black" coils, but only and exclusively "white" ones!

[ivconic]

This is going well for me!
Maybe I should have been a Picasso and not a professional tinsmith!

[ivconic]

I don't want anyone to think I'm biased!

[ivconic]

Many will think that the whole topic is a mix of meaningless things.
I have a very precise way of writing topics and I always try to get a clear message across.
But I want to reject all laymen right from the start and my messages are mainly intended for experts.
But experts often suffer from complacency and very often overlook these important messages.
In short, this entire topic carries only one message!
Addressed to decision makers in XP.
Icon seems like the right move.
But if it is sold with "black" coils then it will be a total failure!
My suggestion to respected experts from XP is to plan the Icon series exclusively with "white" coils right from the start... if they want the whole story to make sense.

[Carl-NC]

I think it's even more complicated than that. SNR (or S/N) can be applied 2 different ways. Noise can be either internal noise or external noise. Internal noise is mostly thermal (resistances) and shot (junctions) and is inherent in the particular design; you can't do anything about it without redesigning it. Therefore, the design can be specified to have a base SNR and you can never do any better than this.

External noise can be from ground or EMI and either will degrade the base SNR. Ground noise is mitigated through ground balance and ground tracking schemes. EMI is minimized with filtering and coherent sampling. MF and PI detectors are typically worse with EMI because they have broadband front ends; SF detectors are narrow band and usually do better, especially when there are multiple incoherent EMI sources.

You can come up with an actual number for the base SNR. You could specify it like an ADC: what is the total integrated noise compared to a full scale target signal? Then you might say, "This detector has an SNR of 72dB." Doing this for ground/EMI is far more difficult because they are situational. But you could, for example, create an EMI rejection spec at, say, 50Hz by using a predetermined 50Hz field source (certain H field at a certain distance) and measuring the SNR degradation, similar to how we measure EMI susceptibility in FCC/CE compliance testing.

[ivconic]

Totally agree with you Carl, really well explained.
The distinction between internal and external noise is spot on, and I like how you broke down the EMI susceptibility differences between MF and SF designs.
That said, I’ve got a specific ADC development PCB on the way from China.
Planning to hook it up to an ESP32 and try out a few DSP techniques, mostly to see if I can push the EMI rejection further and improve the effective S/N ratio
beyond just filtering and coherent sampling.
Might not beat the base internal noise floor, but hopefully it helps with the external stuff.
Truth be told, my "technical English" is not perfect, I often use terms clumsily, that's why I don't often participate in deeper analyses.
I understand things better - than I can explain them in words.
This time it is about the core of the matter that interests me directly.
So that I don't turn out to be funny like Tarzan; I had to ask for AI help here to form meaningful sentences for me.
If I understood correctly, coherent sampling means that the sampling frequency and the signal frequency are synchronized so that an integer number of signal cycles fits
exactly into the sampling window. Exactly as I actually planned to do!
In practice, you lock the sampling clock to the signal of interest (say... the TX frequency in a metal detector).
This way, spectral leakage is minimized, harmonics are neatly aligned, and the DSP can effectively "tune out" unrelated EMI noise.
In SF (narrowband) detectors, this works particularly well; you're essentially forcing the ADC to look at the signal synchronously, so any asynchronous
interference (like most "EMI") gets averaged down or rejected.
It's one of the cleanest non-filtering ways to improve S/N against external noise.
But I'm not overly afraid of DSP either, ESP has enough horsepower to withstand heavy filters, even a combination of several of them.
Some time ago I sent you an interesting video on email.
I temporarily stopped that job; precisely because I am waiting for the ADC dev pcb to arrive.
What you saw in that video is with the internal ESP32 ADC.
The results are quite good but far from "professional".
My hopes are to achieve something more with an external ADC.
But the whole story revolves around "EMI" and especially "S/N".
So these few posts are very helpful for me.
Thank you!

[ivconic]

[ivconic]

These teasers are getting more and more interesting.
But one thing still makes me "unhappy" - I don't see a white coil anywhere!
"Under 600 euros..." is good news; provided they add a white coil!

[ivconic]

Ha!
Now it was no problem for them to put a regular "USB-C" connector on the "bone" headphones!

[Riss]

I have been waiting for stereo sound for a long time. I have never worked with Deus, but many seekers are dissatisfied with Deus 2 - "fast, but shallow detector". "light, but unbalanced" - tie a bottle of rakia under the elbow pad to move the center of gravity to the back and reduce arm fatigue - is my advice Experienced searchers in Bulgaria prefer the Equinox 800 (900) - surprisingly deep with 15" x 12" (38 см) DD over the Deus. However, their VDI numbers "jump" too much and the good old Spectra V3 (Whites) performs better - we have done such a parallel test.Since almost the entire detector is in the probe, and these probes are of a new design - it is better if they are white (the sun heats up the black ones a lot).Deus - God, ICON - icon - church series of detectors... Ivconic - explain please what is the difference between the white and black probes - the operating frequencies?

[ivconic]

Some good observations Riss, I agree!
Rakija is no longer in the game for me, now I use much harder drugs!
In the meantime, a new teaser video has been released in which we learn some details.
One detail is that the Icon is compatible with the HF coil for the Deus 2.
That's what I wanted to know! Ok, one less worry.
What is the difference between "black" and "white" coils?
Life is easier for me when I simplify things and that's why I call them "black" and "white" coils.
When I speak in the plural; then it refers to Deus 1, there are two "white" coils for Deus 1, round and elliptical.
I now have an ellipse, and in the past I also worked with a round one.
And when we talk about Deus 2 (now also Icon); there is, as far as I know, only an elliptical white coil for now.
The difference? In my case (I have to hedge, I can't claim for all other cases); the difference in behavior is HUGE!
Let's say, the same terrain, a steep rocky hill, an ancient terrain from the 4th-5th century, a lot of low vegetation and bushes, a lot of mineralization,
a lot of small ceramic parts... but also a lot of valuable finds (once upon a time).
The black coil "sings" non-stop and gives all possible useless signals and reactions... the white coil, following the same path, is silent all the time,
sometimes I wonder if the detector is even on!
Differences in "depths" (black is 22.5 cm, same as white round); there is no difference, even sometimes the advantage is on the side of the white coil.
The black coil from the first series (I have one) works at 4 fixed frequencies, with 18kHz being the highest.
The white works at higher frequencies, I don't remember exactly around the round white but now my elliptical white works up to 70kHz
(or 80kHz, can you believe I don't remember!? For the simple reason that I mostly use it at around 30kHz).
It's hard to describe the differences other than to say the difference is HUGE.
I can philosophize here for hours, nobody wants that, I have enough drugs... but there is no need for excessive rhetorical diarrhea,
just accept my words and that the difference is HUGE... on my fields here!
I always speak for myself and only mean the terms I have here.
I cannot speak for others.
It's not my fault that most of the people on the forum are autistic.

[ivconic]

Here are the specs in brief, most of them don't interest me much, but what interested me was the question of whether the Icon will work with a white coil:

[ivconic]

Listen... the reason why I don't remember all the details
(although my Deus 1 with white coil is here in the drawer next to me) is because I stopped "adoring" certain models a long time ago,
now I have too many detectors, each of them does the job for me more or less, the differences at the end of the day are very small...
and that's why I don't have so much enthusiasm (as I used to) to glorify and "adore" certain models too much.
And Deus is just one of the detectors I have. So much for that. I'm not superficial, I've simply put things in place in my head over time.
The time of excessive mystification has long passed. They are just more or less expensive toys.
There are fields around me that I visit regularly. Often I don't really care which detector I bring.
Sure, I love questing success, just like everyone else, but there's too much mileage in my head and legs.
Today it is no longer my main motivation.
Today, my main motivation is to go out into the wilderness and have a great mental relaxation in those few hours.
Escape from everyday life and "cleansing" the mind.
Of course, any new detector that strikes me as interesting; I like to try it and take it with me.
I have never been a "Youtube detectorist" and have remained so until today.
That's why I'm not at all interested in YouTube successes, which most people push.
I leave that nonsense to the younger ones.

[ivconic]

There is one more thing, which I have avoided mentioning in public and here on the forum for a long time.
Because even though I seem different; I'm not someone who enjoys harming others after all.
My sometimes fierce criticisms and provocations are mostly constructive... or at least I try to be.
But now I have to tell one of my experiences, because in the context of this topic it may be useful and explanatory.
What about the "black" coils from the X35 series? What are my experiences?
Hmmm... they're not great at all!
I had X35 on both Deus 1 and Deus 2, the 28cm one (or 27cm...)
Is that literally "X35" on Deus 2? I have no idea, I was never interested, it said "MFM" or something.
But in my small town, which barely has ten thousand inhabitants; there are too many detectors. The vast majority are XP models.
And a lot of ML. Let's say the ratio is 70% to 30% in favor of XP.
The vast majority of XP users have that black 28cm coil.
Locals often call me "serviceman" and whenever they have problems; turn to me.
The number of failures in the operation of those black 28cm coils is unbelievable! Simply incredible!
The higher percentage of failures are on X35 black coils for Deus 1 so far.
Because Deus 2 is less represented and that's why the percentage is lower.
From 2012 until today, I have had ONLY ONE white coil fail!
And over 20 cases when it comes to 28cm black coils.
And when I talk about the oldest series of black coils, 22.5cm and 34x28cm ... NOT ONE CASE OF FAILURE so far!
That's my local stats. And I base my opinion on that. Why else would I?
This story speaks for itself. I don't think any further comments are necessary.
But that's another reason why I insist on white coils.
In all those cases; no fix! The user is exposed to an additional not very small cost!
Spend an unplanned 340e or 440e for a coil (these are the prices here); that is a severe insult to intelligence!
Ok, I know what some will say; it's not an ordinary coil, actually the whole detector is placed in a coil... so what?
Can only coil do the job for you?
If it's possible, then you don't need a remote control or "smart" headphones, just take a coil and walk around the fields like a j-erk!
Those black new coils break too much, too much!
There are various symptoms and manifestations of malfunctions.
That would require a whole new thread.
I have no will for it.
If I did XP damage with this; I'm sorry, that was not my intention.
But it is a simple truth that had to be said sooner or later.