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Some here’s have said VLF detector tech has reached its limits

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tnsharpshooter

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Is this true?
Imo no.
Now some folks said this even prior to Deus 2 release.
I plan on doing a few tests and videoing.

I believe the tech is more close to being at the limits now with Deus 2 in the pack.

Most of this though believe it or not may be attributed to audio presented on detector.
Yeah faster processor and yes the audio has to be engineered to bring the higher processor to give more of advantage. Also the wi stream (non blue tooth) with headphone use is helping too.

So wonder if we compare Eqx using external speaker to Deus 2 using headphones. What happens? Remember using external speaker with Eqx the blue tooth delaynis removed. Yet Deus 2 will be subjected to some delay using the wi stream. Remember though Deus 2 coil is also sending data via stream. Not using cable like Eqx.
Now I am only mentioning Eqx here as an example.

More to come on this topic.
 
Truth be told. Using audio alone to human ear pute limits on actual VLF ops.
A signal if given has to be so long (audio wise) for human ear to hear. Wonder if a detector can actually be detecting a nonferous (circutry) sees it. Yet tonal presentation presented human ear can’t discern. This could be aggravated by VLF detector ops how it behaves in the actual detecting situation in iron.

A VLF detector could be actually misengineered where as detector is seeing nonferrous yet from audio standpoint detector fails to give audio or enough audio to user.
 
From my experience with the three latest advanced simultaneous multi frequency VLFs (Equinox,Deus 2, Legend......ACE Apex and Vanquish are not included), all have some differences in how they are inherently setup at least in their current software/firmware versions as far as how sensitive they are to short time constant targets and longer time constant targets which effects both sensitivity to the full range of non-ferrous targets and ferrous targets along with how well they can handle high levels of magnetite mineralization and salt mineralization.

They are a big improvement over most single frequency detectors that use frequencies below around 20 kHz. They also have much faster target recovery speed, better target separation and will work on a wider range of iron and salt mineralization than earlier versions of simultaneous multi frequency detectors.

However, I think there is still plenty of room for improvement and possibilities.

I am linking one of my favorite articles that I wade through periodically. It is at least 15 years old (maybe more like 20?) and explains VLF detector technology very well and is still very applicable to todays VLF detectors.

tnsharpshooter, I am sure that you are familiar with this article. Others might not be.

https://www.minelab.com/__files/f/11043/KBA_METAL_DETECTOR_BASICS_&_THEORY.pdf
 
There is plenty !ore room for development for Sim MF VLF detectors...All there may limitations of audio, there is lots of room for improvement on the display of info....More accurate and extended range TDI for a start, plus improved versions of the various graph displays or some other form of visual presentation of data..

And the first company that introduces a reliable form of aluminium discrimination is going to do really well...
 
You know the ole saying audio is king. Yeah today detectors the truth.
But I wonder about this sometimes.
Could a VLF detector actually give more info (showing nonferrous) with visual better. Granted user wouldn’t get audio necessarily.
Sorta like that detector Nokta Makro makes.
Where the coil is swept.
Visual info is displayed.
So could a person look at and review and after fact go back and locate the nonferous. Yeah. Sounds corny. But imagine if we indeed had navigation capability that could be employed that was super duper accurate. Far more accurate than the tech today. Where one could take their coil to a say 1 ft square (an example) after the fact and investigate again watching visual data and yes maybe even audio data.

Maybe I should be careful of what I wish for. Lol

Yeah when we sweep our coils today. The info is gotten but not recorded. True we may remember some targets or detector behavior on a spot on a site based on say a landmark. I do this actually and have commented on in some videos.
But going a different route the info the detector gets could be recorded for further study. Only thing is we need reference to get us back to the spot where the info was actually gotten. Or very close to the spot.
 
Disclaimer here. I have zero engineering degrees.
Anyone here feel free to weigh in on this thread. Even the engineers who are members here.
Let’s talk about tones.
Back some time ago and I can’t remember for sure which detector Keith Southern was talking about. It could have been CTX 3030.
Anyways he basically said long tones,using a big no no.
Well.
Thinking about this and using many other VLF detectors. Plus this one of the latest Deus 2 detector.
Thinking out loud.
Could using long tones on any detector really (assuming) it will detect a nonferrous in some given scenarios. Could using long tones have advantage some times when differentiating and bring to audio a nonferrous target. Say inna one on one ferrous /nonferrous scenario? Whereas tone given longer hence easier to hear (recognize). But the same long tone use if in a multiple say single ferrous yet multiple nonferrous the long tone use have indeed a disadvantage?

You see this is where I even I get somewhat confused.
We see Xp has gone the shorter tone route. They offer no long tone option on Deus 2.
So a VLF detector is swept. In say a one nonferrous scenario yet multiple ferrous object scenario. The detector sees the ferrous and sees the nonferrous and then sees the additional ferrous. So it seems some detectors are cutting off from the say the nonferrous tone when thr second ferrous is felt/seen. So tone could indeed could be shorter. Would long tone use here give more advantage?
Or could a detector be swept over a ferrous target using long tones and then coil comes over nonferous, and detector doesn’t report nonferous target ever tonally, due to lag (of using long tones)? Coil sweep speed could drive. Or does the detector eventually reset the nonferous but the coil is far far away from object actually detected.
Yeah lot happens fast with electronics. And nailing this all down using one’s ears or even eyes not easy. At least for me.
 
I thought I read GOV controls what freq's and power that can be transmitted on a detector? I thought that is what is holding them back.
Maybe someone like Nokta could answer this for me.
 
GreenMeanie said:
I thought I read GOV controls what freq's and power that can be transmitted on a detector? I thought that is what is holding them back.
Maybe someone like Nokta could answer this for me.
Click to expand...

A detector does not transmit electromagnetic waves. The coil does emit a magnetic field over a relatively short distance when it is pulsed, but that is not the same as an electromagnetic wave that radiates out for long distances.

To my knowledge, the government does not control what frequency and power a detector can use.
 
f18d8e4b95f7dc4482b1d2325c7c2f92ceb55b9c
:laughing:
 
GeoW said:
f18d8e4b95f7dc4482b1d2325c7c2f92ceb55b9c
:laughing:
Click to expand...

Why do you think that Maxwell's equations in integral form are funny? More specifically, bringing the differentiation operator inside the integral in what is really Faraday's law? :?:

Some people have a strange sense of humor. :roll:
 
Rudy said:
A detector does not transmit electromagnetic waves. The coil does emit a magnetic field over a relatively short distance when it is pulsed, but that is not the same as an electromagnetic wave that radiates out for long distances.

To my knowledge, the government does not control what frequency and power a detector can use.
Click to expand...

Has anything changed as far as fcc requirements in USA.
Here’s old thread link.
Talks about detector Xp Goldmaxx. Made in France.
I will post thread link.
And a copy of excerpt from thread.
I heard there was concern for things that might for example open garage doors,,etc inadvertently. Hence fcc does manage/approve freq of whatever.

https://www.dankowskidetectors.com/discussions/read.php?2,27596,27649#msg-27649

Excerpt from thread.
April 10, 2012 10:59PM Registered: 12 years ago
Posts: 925
Daniel Tn Wrote:
-------------------------------------------------------
> Interesting....so the question I have now, is
> since you've tested both machines....and found
> them very comparable to one another...would it be
> more beneficial to buy a Gold Maxx since it has
> several different sizes of aftermarket coils
> available for it, that don't cost $500+?


The Goldmaxx Power is not available in the USA. It has not been approved by the FCC because of the wireless headphones that are available for the unit.
 
Rudy said:
Why do you think that Maxwell's equations in integral form are funny? More specifically, bringing the differentiation operator inside the integral in what is really Faraday's law? :?:

Some people have a strange sense of humor. :roll:
Click to expand...

Just providing couple of the wizards something to laugh at.
 
GreenMeanie said:
I thought I read GOV controls what freq's and power that can be transmitted on a detector? I thought that is what is holding them back.
Maybe someone like Nokta could answer this for me.
Click to expand...

Ground is magnetically polarizable, so the more power you transmit, the more the ground lights up, so increasing transmit power will have diminishing returns (we are already there). Too much power and you can't tell deep objects from the ground itself, and it will actually interfere with the detectors ability to discriminate as well.

This is why you lose depth in highly mineralized ground. Since the ground signal is omnipresent, its signal strength increases at a greater rate than that of deep objects with respect to transmit power, causing them to "fade to iron / ground". So at depth, the ground signal begins to overpower any non-ferrous signal, averaging it out to the ground.

In theory you could design a detector with slightly higher transmit power but it will only work in non-mineralized soil. It would end up being a bad product because it would be near useless anywhere with mineralized ground.
 
Last edited:
You can always add more mirrors to your car to improve backing up, but they will not make your car go any faster,


VLF I'm sure has more tricks up its sleeve, but I don't believe more depth is one of them. That is where most believe VLF technology has hit a wall. I have to agree. Not in 20 years have we seen any gain in depth. And not the idea that new tech makes so in a site I was only getting 5" and now I get 7", but raw depth where it really counts.
 
tnsharpshooter said:
Has anything changed as far as fcc requirements in USA.
Here’s old thread link.
Talks about detector Xp Goldmaxx. Made in France.
I will post thread link.
And a copy of excerpt from thread.
I heard there was concern for things that might for example open garage doors,,etc inadvertently. Hence fcc does manage/approve freq of whatever.

https://www.dankowskidetectors.com/discussions/read.php?2,27596,27649#msg-27649

Excerpt from thread.
April 10, 2012 10:59PM Registered: 12 years ago
Posts: 925
Daniel Tn Wrote:
-------------------------------------------------------
> Interesting....so the question I have now, is
> since you've tested both machines....and found
> them very comparable to one another...would it be
> more beneficial to buy a Gold Maxx since it has
> several different sizes of aftermarket coils
> available for it, that don't cost $500+?


The Goldmaxx Power is not available in the USA. It has not been approved by the FCC because of the wireless headphones that are available for the unit.
Click to expand...

Just because it has been discussed before, here and in other sites, doesn't make it a fact. If the FCC does indeed regulate the amount of transmit power a detector can use, then it would be a simple matter of providing a link to that section of the FCC regulations, if they do exist. For example, something like Part 95 of the Rules regulating Family Radio Service (FRS).

The FCC does indeed limit the amount of radio frequency interference (RFI) any electronic device can produce, but that doesn't mean it limits the amount of power into a detector's transmit coil.
 
AccurateCalls said:
Ground is magnetically polarizable, so the more power you transmit, the more the ground lights up, so increasing transmit power will have diminishing returns (we are already there). Too much power and you can't tell deep objects from the ground itself, and it will actually interfere with the detectors ability to discriminate as well.

This is why you lose depth in highly mineralized ground. Since the ground signal is omnipresent, its signal strength increases at a greater rate than that of deep objects with respect to transmit power, causing them to "fade to iron / ground". So at depth, the ground signal begins to overpower any non-ferrous signal, averaging it out to the ground.

In theory you could design a detector with slightly higher transmit power but it will only work in non-mineralized soil. It would end up being a bad product because it would be near useless anywhere with mineralized ground.
Click to expand...

Thank you. This is one of the two main reasons there is a limit to how much power you can put into the detector's transmit coil.

The second reason is a marketing one. Simply, how long do you want the batteries to last before they are depleted. Alternatively, how much weight (battery storage capacity) do you want the detector to have?

It is these that determine how much power a detector can have and not an FCC regulation.
 
VLF reached its limit with Minelab's SMF and it's derivatives.

The future of metal detecting is in imaging detectors. Like Nokta Makro's Invenio project.
 
Rudy said:
Just because it has been discussed before, here and in other sites, doesn't make it a fact. If the FCC does indeed regulate the amount of transmit power a detector can use, then it would be a simple matter of providing a link to that section of the FCC regulations, if they do exist. For example, something like Part 95 of the Rules regulating Family Radio Service (FRS).

The FCC does indeed limit the amount of radio frequency interference (RFI) any electronic device can produce, but that doesn't mean it limits the amount of power into a detector's transmit coil.
Click to expand...

I was referring more to frequency used with device. I don’t know the answer. Does fcc regulate frequency?
I can understand where a device would conflict with other devices. Might even open up a bank vault. Who knows.
 
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