coil advice wanted. small or large.
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SMELLYJELLY
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coil advice wanted. small or large.
Hi guys an girls.. What it is, im using the explorer se with 13" ultimate coil. I have this one permission, a very small field that has winkled me out 2 very small thin hammereds ( irish john & henry 111 pennies) and only got a slight signal at only about 6 " depth. would i be better going for a small 6 " coil or would a large wot coil over sensitise it. Im sure there will be more in the ground so dont want to waste money on a large coil even though it would cover more ground. settings i use are open screen on ferrous 32 auto and deep on threshold just audible. thanks sj
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jcmaloney
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Small coils like the SEF do punch very deep, however not much more than a larger coil (physics & electronics!).
You will lose ground coverage with a smaller coil but with the large coil you are more likely to pick up contrasting/interfering "other" signals and the largest mass will win!
Large coil: Medium iron and small non-ferrous detected at the same time it will either null or the larger target "wins".
Small coil: Small non ferrous is primary/only target.
On balance a smaller coil is more accurate on target ID and is more likely to pick up feint whispery signals from deeper targets.
Hope that helps!
You will lose ground coverage with a smaller coil but with the large coil you are more likely to pick up contrasting/interfering "other" signals and the largest mass will win!
Large coil: Medium iron and small non-ferrous detected at the same time it will either null or the larger target "wins".
Small coil: Small non ferrous is primary/only target.
On balance a smaller coil is more accurate on target ID and is more likely to pick up feint whispery signals from deeper targets.
Hope that helps!
Opinions expressed on MY posts are mine and NOT those of any democratic organisation I volunteer for.
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Saffron
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I found this page very useful when looking for an additional coil for my Ace 250 earlier his year
http://nel-coils.com/index.php/en/
Although that is for Nel coils it would be a general guide to other makes.
With the larger coil you obviously gain ground coverage (which was my main requirement), you also gain depth. But you lose out on seperation of targets and finding the small items.
You might also need to consider the extra weight.
The opposite is true of the smaller coils, you obviously lose ground coverage, you also lose depth. But you gain on seperation of targets and finding the small items.
Evan
http://nel-coils.com/index.php/en/
Although that is for Nel coils it would be a general guide to other makes.
With the larger coil you obviously gain ground coverage (which was my main requirement), you also gain depth. But you lose out on seperation of targets and finding the small items.
You might also need to consider the extra weight.
The opposite is true of the smaller coils, you obviously lose ground coverage, you also lose depth. But you gain on seperation of targets and finding the small items.
Evan
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fred
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The choice of coil largely depends upon the land you are doing.
If it has lots of iron then a WOT sized coil may not be the best choice unless you are trying to punch deeper to detect larger coins. A 13" SEF or similar, like you are currently using, should give a few more inches depth over the standard coil on coin size targets without losing sensitivity to anything of importance. Assuming that you still have it, I would be tempted just to give the field a going over with the standard coil, which is a very good one anyway. If you do find more good targets you could then consider going down another step.
If it has lots of iron then a WOT sized coil may not be the best choice unless you are trying to punch deeper to detect larger coins. A 13" SEF or similar, like you are currently using, should give a few more inches depth over the standard coil on coin size targets without losing sensitivity to anything of importance. Assuming that you still have it, I would be tempted just to give the field a going over with the standard coil, which is a very good one anyway. If you do find more good targets you could then consider going down another step.
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SMELLYJELLY
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Some great advice there cheers guys.. I have other permissions with a lot of stubble etc so a small coil might be of use there too.. My main target are the small hamereds in this case so finding just one extra will make it worth while. Sj
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