detector coils

[madmantrapper]

What effect does the diameter of the coil have?

 

[Loco-Digger]

Basically the larger the coil the deeper it detects. You give up target separation though. Just know that a larger coil has more of a chance of having more than one target in its detecting field. I have 4 coils for my machine. I use the large coil in target sparse sites such as fields. Some places I need better target separation so I go with a smaller coil.

There are 2 basic types of coils. Concentric and DD. The pics below shows how they scan the ground. I prefer DD coils over concentric coils.

Concentric coil


DD coil


Hope this helped.

 

[devldog]

You pretty much nailed it Loco. Well Done.

 

[madmantrapper]

Yes this helps greatly. Thank you

 

[cudamark]

Also, as a general rule, the smaller coils will be more sensitive to tiny targets than a large diameter coil.

 

[Loco-Digger]

Also, as a general rule, the smaller coils will be more sensitive to tiny targets than a large diameter coil.

I thought that frequency of the detector has more to do with what you mentioned than coil size. The higher the freq, the smaller the target it can detect is my understanding.

 

[Slowtaknow]

It does on gold, plus smaller equals smaller gold

 

[cudamark]

I agree. Both size and frequency play a part in tiny target detection. I didn't mention frequency because the OP was just asking about the effect of size. Concentric and DD design will also slightly effect sensitivity to tiny targets.

 

[A2coins]

Talk to Nel tech or Garrett teck I have the nel attack and the garrett 5x8 you will lose depth on dime size targets absolutely. They are great for quarter and larger and relic hunting

 

[George (MN)]

Talk to Nel tech or Garrett teck I have the nel attack and the garrett 5x8 you will lose depth on dime size targets absolutely. They are great for quarter and larger and relic hunting

My 13" Detech Ultimate coil for AT Pro beeps on a dime with all high tones at 13" in an air test, which is 3" more than stock coil. In ground it can often go deeper than stock coil as well. My 15" Mars Goliath coil air tests with high tones on dime at 12". My NEL Thunder 10.5x14.5 air tests on a dime at 11.5", again better than stock coil. In extremely trashy areas, smaller coils may provide more coins due to separation, despite less depth.

 

[A2coins]

air tests make no sense you have to account for mineralization ect your coil defies logic Awesome

 

[Eleven Cents]

I don't know if a small coil helps with really small targets like tiny gold flakes. But I can tell you that my Tesoro 11x8 DD has no problem hitting pieces of can slaw the size of an office hole punch.

 

[ink]

Why would you take a 12 inch double D coil into a junkard when searching for a lost class ring ??

 

[gunsil]

In GENERAL, a concentric coil of the same diameter of a DD coil will penetrate deeper although the deepest part will be much smaller than the deepest edge of the DD. In GENERAL, a larger coil will go deeper but will lose sensitivity to smaller targets and a smaller coil will provide better separation and better sensitivity to smaller targets. Been this way from the git-go and will likely never change. A2, my 8" coil on my safari has no problem with dimes or reales at 10+ inches, I seriously doubt the 8x5 Garrett won't see dimes well, dimes are actually fairly large targets. I have banged silver dimes to 8" with my ATP and 8x5 coil. Depth is often overrated anyways, in forty plus years of hunting many of my coins have come at 8" or less and most at 6" or less.