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Ridge Runner

Why Are Some DD Coils As Big As Hula Hoops?

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Lots of detector companies have stop making big round DD coils but others still putting out a large round one.

What I’m wondering if the large round DD coil is better than a slim DD with less weight?

I know swinging my 6x10 DD on my Sport is less effort than the stock DD that comes with it.

I could understand if we were talking about a concentric coil being larger for more depth.

Please enlighten me someone!

Chuck

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In a nutshell...Bigger the coil = deeper detection depth but then the item detected needs to be bigger as well. l Dont think there are too many big lunker nuggets around now that warrant swinging a large coil these days. Unless in a known area for big nuggets & the area is suitable for swinging a large coil. But then what do you call big, 14" 16" 18" 22" or 25 inches?, & what do you call deep?

Good luck out there

JW :smile:

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JW

If it’s a concentric coil the bigger well give you more depth.

The stock coil on my Sport is 10 “ round and the other is 10” but it’s 6x10” with both a DD. I’m talking about DD coils only and most now is a slim DD. The length can be whatever you want but the width is somewhat less than the other.

What’s the difference if any between the two other than weigh.

Chuck

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The coil with the larger surface area generally gets more depth, all other factors being equal. Both length and width matter, not just length as you seem to be implying. A round 10” DD is normally going to get more depth than a 6” x 10” DD.

Tech notes - About Searchcoils by Dave Johnson and Coil Basics by Carl Moreland

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Steve

I thank you for your reply. It looks as if I something to read to help me understand the workings of a coil better .

Chuck

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5 hours ago, kiwijw said:

In a nutshell...Bigger the coil = deeper detection depth but then the item detected needs to be bigger as well. l Dont think there are too many big lunker nuggets around now that warrant swinging a large coil these days. Unless in a known area for big nuggets & the area is suitable for swinging a large coil. But then what do you call big, 14" 16" 18" 22" or 25 inches?, & what do you call deep?

Good luck out there

JW :smile:

All the little specks are gone now that JW has a 6 inch coil 😢

  • Haha 2

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