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Steve Herschbach

Fisher Impulse AQ Discrimination Explanation

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8 minutes ago, okara gold said:

Alexandre... Your chart is very encouraging! 

So... In All Metal mode 10K rings will be detected along with everything else.

By using some amount of discrimination, can 10K rings still be detected? 

Merci !

If the carat is low, it will be easy to detect in all modes.
If the carat is high and the jewelry is heavy (24K and> 4grs) then it will be difficult not to reject it and continue to reject ferrous in the same time.

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I’m starting to appreciate the flexibility in the operation of the AQ......but for me and my hunting conditions, I can see the pure AM mode the one to use.

Beaches down here have very little iron targets (big or small)

We have quite a lot of Asian gold = 22 K as well as the big, hairy guys with the ounce plus nuggets around their necks. 😳

I can find quite a lot of money because of our $1 and $2 coins which need to be “captured”.......maybe this is possible in one of the ID modes. These coins are quite high up on the conductivity scale.

 Thanks 

Tony

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Yes it's possible
we can just cut the hairpin
and take the 22 and 24 k
with almost no loss

for different currencies
everyone will have to do tests ....

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Such nice civilized discourse - how I miss it other places.

Thanks Steve.

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Thanks Alexander for that diagram.  I was hoping that with the discrimination mode you could discriminate the coins of 1, 2 and 5 cents.  Around here most of the beaches are full of these coins that are useless, not even for the legal course, as they deteriorate greatly.  I leave an example of how those coins come out

20200109_113738.jpg

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Hi , yes I agree with Luis , tiny bits of iron like the euro 5cent above and very small nails will not be rejected by the AQ if I understand well. Could you confirm this alexandre ,  because those very small nails/bits of iron are not shown in your diagram. Thanks … Alain

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42 minutes ago, palzynski said:

Hi , yes I agree with Luis , tiny bits of iron like the euro 5cent above and very small nails will not be rejected by the AQ if I understand well. Could you confirm this alexandre ,  because those very small nails/bits of iron are not shown in your diagram. Thanks … Alain

And in North America the Canadian coins with their composite cores!

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hmmmm.

How small of an item can I go down to with 7 ns pulse delay?

HH

Mike

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On 1/9/2020 at 9:38 AM, Mike Hillis said:

How small of an item can I go down to with 7 ns pulse delay?

There have been various posts already that explain that the Impulse AQ is locked in “salt mode” and by design is not set to pick up the smallest gold i.e. aluminum even while in all metal mode. The Impulse is designed to pick up gold rings specifically and particularly the “sweet zone” where the most gold by weight occurs while excluding everything else.

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4 hours ago, palzynski said:

Hi , yes I agree with Luis , tiny bits of iron like the euro 5cent above and very small nails will not be rejected by the AQ if I understand well. Could you confirm this alexandre ,  because those very small nails/bits of iron are not shown in your diagram. Thanks … Alain

The small iron is rejected and makes a double beep, but the coins with a layer of copper like the 5c no.

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      Koch, C.B, Borggaard, OK, and A. Gafur. 2005. Formation of iron oxides in soils developed under natural fires and slash-and-burn based agriculture in a monsoonal climate (Chittagong Hill Tracts, Bangladesh). Hyperfine Interact 166, 579–584.
      Rivers, JM, Nyquist, JE, Terry, D.O., and W. E. Doll. 2004. Investigation into the Origin of Magnetic Soils on the Oak Ridge Reservation, Tennessee. Soil Science Society of America Journal, Vol. 68 No. 5 p. 1772-1779.
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