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Gold Detecting And Prospecting Forum Was Discussing On Or Off Topic Gold Topics


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So I thought I would throw a spanner into the discussion. Here goes.

We have heard of the double D coils what about a triple D coil. Well that outside my knowledge but let look at a quad D coil the oldest ground balancing coil. Have a look at these links.

....LINK....
https://www.phys.k-state.edu/reu2011/nnorvell/Metal_Detector_Research.html

and more detail.

....LINK....
http://41.67.20.41/bitstream/handle/123456789/18621/Metal%20Detector.pdf?sequence=1&isAllowed=y

Are we on topic.

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Regards Geof.
geof_junk
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Geof:  Interesting question and interesting first article.  I personally have never read of anyone making a 4-D coil  so I am curious if such a configuration has been investigated and if so what were the results?  I was unable to access the second link.  Thanks for posting an intellectually stimulating question.

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1 hour ago, Cascade Steven said:

Geof:  Interesting question and interesting first article.  I personally have never read of anyone making a 4-D coil  so I am curious if such a configuration has been investigated and if so what were the results?  I was unable to access the second link.  Thanks for posting an intellectually stimulating question.

The site has some problems...... It was a good write up on coils in the preamble I got ¾ of the way though it. I will try and get on it again when the site get back up as it had a lot of technical details in it over 40 pages.  The site error listed below.

This site can’t be reached

41.67.20.41 took too long to respond.

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My first post here, coil-related, so I hope it's not too off topic. Two more spanners...

First off I hunt residual gold mostly, not transported alluvial stuff and until I started nugget hunting a lot two years back I always thought that the term "gold patch" was just that, a term. To my surprise I've found that nuggets cluster really tightly. Although the district is a few square miles patches are no more than a hundred square yards with a whole lot of nothing between patches. So I tend to visit a patch multiple times. 1st pass-discovery, 2nd pass- move all the rocks, 3rd pass buy a PI and try again!

 Question 1 Is there a really thorough article somewhere on using no-motion mode? Both Garret and Fisher kinda cough and shuffle their feet on the subject saying it's best left to experienced users. Well, thanks guys that's real helpful! 

Question 2 (Full disclosure - I was an exploration geologist for many years and came up against EM systems) Has anybody ever used a relatively large, fixed transmitter loop and a roving receiver for nuggets in known patches where the soil profile is way, way thicker than even a GPZ's range. It's a standard technique in metals exploration and the large tranmitter and the ability to put more current through it would seem a no-brainer to get more depth in great patches that have been hammered?

BTW I really enjoy this site and the discussions on it. Thanks.

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  • Steve Herschbach changed the title to Gold Detecting And Prospecting Forum Was Discussing On Or Off Topic Gold Topics.

 Question 1 Is there a really thorough article somewhere on using no-motion mode? Both Garret and Fisher kinda cough and shuffle their feet on the subject saying it's best left to experienced users. Well, thanks guys that's real helpful! 

None that I have seen. There would not be much to write about. Non-motion mode simply lacks an SAT function, so you have to be on top on the manual tuning. That’s it in a nutshell.

Question 2 (Full disclosure - I was an exploration geologist for many years and came up against EM systems) Has anybody ever used a relatively large, fixed transmitter loop and a roving receiver for nuggets in known patches where the soil profile is way, way thicker than even a GPZ's range. It's a standard technique in metals exploration and the large tranmitter and the ability to put more current through it would seem a no-brainer to get more depth in great patches that have been hammered?

Tow Coils

Max Depth

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Steve

Thanks for the links. I liked the tow coil post. Basically an airborne system flying at zero feet! My ground is too rugged for that but I recall that an early base metal EM system had the operator wearing a 5-6 foot coil like a giant hula hoop. One for the back-burner....

Next trip I'll blow the dust off my GB Mk1 for which I have a 14" aftermarket coil, pay attention to ground balance and give no-motion a shot over a hammered patch.

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  • Steve Herschbach changed the title to Gold Detecting And Prospecting Forum Was Discussing On Or Off Topic Gold Topics

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