Standardized Tests for Metal Detectors

[Nupi]

You already are telling us now...
If that is all about playing with phase; than we have some starting point!
How about if we scope the front end output and see what changes are produced when needle is swing in front of the coil?
Must be some changes in signal, right?
But you are lucky now because i don't have scope no more, i sold it last year and stopped to do Electronics.

P.S.
XP owner's email is public, you may contact him at their official site.
He is polite man, he will reply to you for sure.

I must be careful because you're a smart guy, but the "secret" is between " " and you know what that means!

[Nupi]

Would be nice to test such setup on soil, don't you think?.............................
[/FONT]

Yes, I also found useful. But I have already done. In # 57 I told it.
The detection distance was about 30% less.
Like I said, I would first increase the detection depth, else you have in practice, not much.

[ivconic]

Yes, I also found useful. But I have already done. In # 57 I told it.
The detection distance was about 30% less.
Like I said, I would first increase the detection depth, else you have in practice, not much.

No, i haven't asked because of the depth loss but from different reason.
Does it work "clean", no chatters, false signals, stable?

[Nupi]

I have several tests in my garden and at first I thought there were a lot of false signals,
but that was not. My garden is a dump.
When remodeling the house they have a lot of waste hidden in the ground.
I checked with my NUPI PP.
I then testing done in the garden of a friend. That was a relief.
I can tell you no chatters,it is not a Deus (joke), false signals, stable, up so far I've tried.
In heavily mineralized ground I have not tested yet. But I've really only done few tests.
I first want to increase depth. The idea is good, undoubtedly.
Regarding the chatters, my MD the threshold should be very low stand as you can hear on the video.

[geoscash1]

Thanks for the video Nupi, job well done... I'm a believer now...

[Nupi]

Thanks for the video Nupi, job well done... I'm a believer now...

Thanks for your comment,
but it's not about whether they believe me or not. To me that's not important.
In another thread I had asked for information about this, so I had comparative examples, but no responses received.
My hope is now MW6 that such experiments also go do.

[green]

Thanks for your comment,
but it's not about whether they believe me or not. To me that's not important.
In another thread I had asked for information about this, so I had comparative examples, but no responses received.
My hope is now MW6 that such experiments also go do.

I've been following both threads. I think of the responses that tried to detect the needles, except for one response saying he could detect some reusable needles you are the only one that has been able to detect them. Congratulations. Doesn't mean much but anything I've tried doesn't look like it comes close. Have you removed a needle and tried detecting just the needle? Hope to one day understand how you are doing it.

[baum7154]

Great results Nupi, but I think the further discussion on detecting needles should continue in the detecting needles thread you started a while ago. If I wanted to find your work on needles a year from now I'd never think of looking in this thread for it. This is a common occurrence on the forum when we get excited/interested in a new topic. I do it all the time too, but I'm trying harder to stay on the thread topics now.

Kind regards,

Dan

[Nupi]

I've been following both threads. I think of the responses that tried to detect the needles, except for one response saying he could detect some reusable needles you are the only one that has been able to detect them. Congratulations. Doesn't mean much but anything I've tried doesn't look like it comes close. Have you removed a needle and tried detecting just the needle? Hope to one day understand how you are doing it.

Please can we go here http://www.geotech1.com/forums/showt...dermic-needles

[Nupi]

Great results Nupi, but I think the further discussion on detecting needles should continue in the detecting needles thread you started a while ago. If I wanted to find your work on needles a year from now I'd never think of looking in this thread for it. This is a common occurrence on the forum when we get excited/interested in a new topic. I do it all the time too, but I'm trying harder to stay on the thread topics now.

Kind regards,

Dan

You're absolutely right, it was not my intention that it would go so. Sorry for that.
It's a good idea to continue this on this thread: http://www.geotech1.com/forums/showt...dermic-needles

regards nupi.

[WM6]

You're absolutely right, it was not my intention that it would go so. Sorry for that.
It's a good idea to continue this on this thread: http://www.geotech1.com/forums/showt...dermic-needles

regards nupi.

For this thread it is enough that we decided to include hypodermic needle in test sample collection.

Other posts regarding those needles better suit to "Hypodermic needles" thread and maybe admin will move (or copy it there).

[Nupi]

I think that's a good idea WM6.

[Jackalope]

Needles are possible for sensitivity testing ... but being elongated they are subject to minor variations due to orientation to the magnetic field. They seem problematic. For standardize testing (worldwide), simply make a particular target(s) the standard, which is accessible internationally. I'd think the easiest are chrome spheres (balls) that are immune to orientation issues and come in standardized sizes. Pick a manufacture to ensure a standard metal content - and that becomes the testing standard.

http://stores.ebay.co.uk/BC-Trade/2-...fsub=473535019

Next, find a way to measure soil matrix content (reactivity, moisture content, soil type, etc.) to make all testing comparable, even though soils will be different. Then standardize the method(s) of testing (everyone performs testing identically) that is easy enough to be replicated by anyone. Not easy, to be sure, but imagine everyone testing their detectors in similar fashion and then creating a single database of test results! That would be something! Finally, some objective results on depth, sensitivity, discrimination, etc. that can be compared across platforms.

Jackalope

[ivconic]

I am still thinking that idea of uniform soil reference is no good.
I am still suggesting that we should find a way somehow to measure our soil references but not to insist on uniform soil conditions.
Simply because we will have much more infos than.
We will see how different detectors perform on different soils.
We will know which one is more suitable for which soil conditions.
Otherwise we may end up again with wrong conclusions about performances (as usually).
There is no "uniform" and "one" soil conditions in nature and not all detectors were made to work the same under same soil conditions.
So i say; we better find a proper method to measure any soil and give it some "index".
That's why i suggested Deus as "soil-meter".
Problem is that many people can't obtain Deus so easily. Though; i bet there is always at least one Deus in a "gang".
Minelab can do the same, yet it is even harder to obtain it than Deus.
Can we figure out method of soil readings which is implemented in Deus and make simpler device for such task?
It would be splendid forum diy project too.
I bet more people will be interested than too, if we offer our "Geotech made soil meter" project here.
I am sure this is the right way to do the things.
First, let's design such "soil meter" here and than we will have tool to "index" any local soil.
I already do know how Deus is performing on my local soils here, though i would really like to see how it performs on soils different than those here.
I would never know that if we take here some uniform soil conditions for our testings.
That's why is better not to stick to only one soil conditions.

[baum7154]

Sound logic Ivconic. I also like the uniformity of the chrome spheres (ball bearings?) presentation to the target, however they are all iron based and that is not a good representation for gold. Also the bearings are not as easily obtained worldwide as a piece of an aluminum can that will represent small gold if cut to a standardized size. For other target simulations they might be ok. The 3/8" iron spheres I have found 'ring like a bell' and are very easily detected with a PI detector.

Regards,

Dan