Cache Test

[Agraz]

Hello Forum, Yes my test isnt deep, is about 2kg, my container are 14cm x 14cm and put in hole about 50cm underground (bottom container) in relation about this topic.

And I think the gold gun is more cientific instrument (long range locators) I have a silver cache (about 20kg) and I want put in my (garden 16m x 16m) in center but underground for test gun and my other detectors, someone know what deep is better?


Also I want find a real gold cache,,, I believe here in Mexico are something. I know the old site, and there one revolution man put he larkspurs in rock fence in 1910, my friend find larkspurs in 1960. I think the gold are in that site or near but undergrond, I need first a cientific long range locator for check/test, but I need money to buy a really long lange locator...

I think this long range locators are cientific: Magnacast5000, EM16, emfad UG12, am I wrong?

[Geo]

Emfad UG12 is not a LRL. It works only for very very big objects as a barrel etc and only when the device is up to the object.

[Agraz]

Hello friends! I forget tell one thing., I miss is that in the place of burial there is more moisture, maybe Carl and the others are missing or need it.

[Agraz]

hello friends, i want to do another test with a collection of silver coins
-how deep is better to do?
-what is the best container?



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the coin is .500 silver, i have 2.500 coins.http://en.numista.com/catalogue/pieces8320.html

[lena27]

http://www.youtube.com/watch?v=8XP3LfCv29Q

[target]

Hi Carl. Good test for America but bad for Europe where there are caches 50..2500 years ago inside metallic boxes. Anyway every test is wellcome.
But a metallic box 2000 years ago inside the ground can more easy detecting than in air.

caches in the UK are usually a wooden box that rotted away or a earthenware pot or even leather bag since rotted away .
sometimes no apparent container was found as they were buried in haste ,marauding Vikings or Saxon invaders on their tales.
the odd roman silver bowl might have been used .

[MattR.UK]

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That's some great testing there.

I would have to disagree with that. I believe that a PI can take advantage of the fact which means higher voltage. Remember that the increase in the coin/nugget's eddy current will be about the same regardless the metal type, to within reason, because the pulse should be fast, meaning it's mostly inductive, not resistive. But when the applied voltage is removed then the coin/nugget will decay at a rate depending on the resistance of the metal.

Well, that's just PI and nothing to do with VLF's, and that's assuming the PI is tuned for the lower conducting metals such as natural gold, not coins.

Paul

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This post is littered with technical errors, and muddled propositions.


(1) that lower conducting materials has a faster di/dt decay time,

Correct in part, but you're not being specific....what about a target's other factors besides its conductivity or conversely, its resistance? Like physical dimensions ratio?

(2) Remember that the increase in the coin/nugget's eddy current will be about the same regardless the metal type,

ABSOLUTELLY INCORRECT: ( and self contradictory....read your own statement as in (1)

(3) because the pulse should be fast, meaning it's mostly inductive, not resistive.

What exactly are you referring to here, the TX pulse or the target's effect on the di/dt 'overshoot'?
All TX pulses are assumed as being 'fast'. (Sharp leading and trailing edges.)
Any references of inductance or resistance can only be related to the target.

(4) when the applied voltage is removed then the coin/nugget will decay at a rate depending on the resistance of the metal.

INCORRECT, due to failure to properly define the full components of ANY target
i.e.......L/R is the 1st order definition of any target such as a coin or gold nugget.

Matt.

[Agraz]

first i check the ground looking for buried metals with two box.


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Now I need to know your opinion to know what is the best container and depth.


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wood or clay?


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-I'm not very interested in testing detectors from above (vertical)
-if I am interested in detecting the coins to the distance (horizontal)
* only try with long range locators, may be: 20-40 meters, not thousands...
i have this 2.500 silver coins for the test (40-50kg),,, for test this i want build
a cientific locator, try develop something or buy something.

[Qiaozhi]

-I'm not very interested in testing detectors from above (vertical)
-if I am interested in detecting the coins to the distance (horizontal)
* only try with long range locators, may be: 20-40 meters, not thousands...
i have this 2.500 silver coins for the test (40-50kg),,, for test this i want build
a cientific locator, try develop something or buy something.

If your intention is to build a test for an LRL, then you would better off going to www.longrangelocators.com.
These devices are no longer discussed here in the Geotech forums.

[Agraz]

Ok, thank you, also i try test metal detectors.

[Skippy]

I've just noticed on Gary's Detecting site that he has tested the XP Deus large coil. He ran it across the buried cache as part of his test procedure, and it gave a hint of detecting it.Here's the link:http://www.garysdetecting.co.uk/xp_deus_coil_review.htm

[simonbaker]

I've just noticed on Gary's Detecting site that he has tested the XP Deus large coil. He ran it across the buried cache as part of his test procedure, and it gave a hint of detecting it.Here's the link:http://www.garysdetecting.co.uk/xp_deus_coil_review.htm

I'm amazed by how short and fast a sweep he uses to detect such a deep target, and how "quick" the response is. It doesn't "feel" deep to me. But perhaps that is because of the "cone" of detection with deep targets, where the mag field is strongest directly below the coil and can make a such short beep. I would think however that a slower responding filter and a slower sweep speed might have a better chance of detecting large deep targets.

-SB

[Skippy]

Interesting that he found 11KHz the most suitable frequency, I would have expected 4kHz to be better, based on the individual coins. It would be interesting to see what an experienced Deus user could achieve on the cache test.

[nicholas]

I read the entire thread and learned some valuable lessons . I do have a few questions though
in regards to cache or hoard detecting if the experts donot mind answering.

1) what metal or combination of ions buried at least 3.5m could give off a halo effect that a minelab 705 (my only detector) could pick up ??

2) I have had a pinpoint on it from -1m before that it was just sound. Im at -2m now and the minelab is reading at the two ends of the TID. Im getting a -8 which is the lowest on the negative scale and +44 +46 + 48 on the other side. I got a few flashes of +20 +32 at some point but lost them later on.

3) Im getting a little bit of a null but it dosent seem like much. Something like a rusty nail .but the signal is really deep. Im thinking if it was just iron, I wouldnt have the + TIDs.

Seeing that this is all relevant to scientific purposes, if anyone can shed any light, it would be greatly appreciated.

Thank you

As an afternote, I think IF its what I hope it is, it shouldnt be more than 65 years old. Would that be enough time for a metal to send such a signal ?? And from the pinpoint, if I guesstimate the depth at another 2 meters, I would think it couldnt be more than 70-80 cm long by maybe 40cm wide. But I may be off on the depth. I cant be sure yet.

[eclipse]

Has anyone tested a minelab GPX series detector on a cache target?
It's really interesting how it performs as it's not yet another VLF/PI detector
and it claims to be deep.