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Metal Detectors
General Metal Detector Discussion
Fake Fisher Gold Bug Pro detectors - be aware!
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<blockquote data-quote="mbasko" data-source="post: 550242" data-attributes="member: 4485"><p>I think the best way to explain it is:-</p><p>Ground Mineralisation </p><p>A small coil puts out a strong field close to the coil so is sensitive. They are better at picking up small shallow gold.</p><p>This can also mean that a small coil can be more sensitive to the ground mineralisation that causes problems so sometimes you need to reduce gain etc. to compensate for the sensitivity.</p><p>As coils get larger they lose some of this close to coil sensitivity (but get better for deep gold) so can be better in troublesome ground. So a bigger coil, with a larger surface area can be better in mineralised areas as they aren't as sensitive to the mineralisation that is close to the coil - hot rocks, hot pockets etc.</p><p></p><p>Outside Interference/EMI</p><p>Where EMI or other outside interference is affecting things going to a smaller coil can help. Think of your coil like an antenna. Small coil - less area to pick up interference. Large coil - more area to pick up interference.</p><p></p><p>The above might explain why your 11" coil seems to run better than the 5" coil (until you reduce the gain then the 5" is ok) in the same area? Could be the ground not the coil.</p></blockquote><p></p>
[QUOTE="mbasko, post: 550242, member: 4485"] I think the best way to explain it is:- Ground Mineralisation A small coil puts out a strong field close to the coil so is sensitive. They are better at picking up small shallow gold. This can also mean that a small coil can be more sensitive to the ground mineralisation that causes problems so sometimes you need to reduce gain etc. to compensate for the sensitivity. As coils get larger they lose some of this close to coil sensitivity (but get better for deep gold) so can be better in troublesome ground. So a bigger coil, with a larger surface area can be better in mineralised areas as they aren't as sensitive to the mineralisation that is close to the coil - hot rocks, hot pockets etc. Outside Interference/EMI Where EMI or other outside interference is affecting things going to a smaller coil can help. Think of your coil like an antenna. Small coil - less area to pick up interference. Large coil - more area to pick up interference. The above might explain why your 11" coil seems to run better than the 5" coil (until you reduce the gain then the 5" is ok) in the same area? Could be the ground not the coil. [/QUOTE]
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Metal Detectors
General Metal Detector Discussion
Fake Fisher Gold Bug Pro detectors - be aware!
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