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Gold Prospecting
Metal Detecting for Gold
Idea For Creating Test Nuggets Of Various Sizes?
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<blockquote data-quote="steelPHASE" data-source="post: 479444" data-attributes="member: 13488"><p>Ok so in basic terms the coil on a PI detector is switched on and off very fast. When its turned off the magnetic field collapses in a fast transient dB/dt. This magnetic transient induces eddy currents in a metal target. From the sudden collapse, the induced eddy currents decay exponentially, with a time constant determined by the characteristics of the target. The decay of these induced eddy currents within a target is what we are looking at. Unfortunately the characteristics of the target are not the same, even for a given material ie gold. The characteristics can vary depending on size, shape, density etc and as we know gold nuggets vary widely from solid lumps to speccies to reef gold etc etc. This is one of the reasons that discrimination is so difficult on a PI machine. </p><p></p><p>Hopefully that makes it a little clearer. </p><p></p><p>regards Pat</p></blockquote><p></p>
[QUOTE="steelPHASE, post: 479444, member: 13488"] Ok so in basic terms the coil on a PI detector is switched on and off very fast. When its turned off the magnetic field collapses in a fast transient dB/dt. This magnetic transient induces eddy currents in a metal target. From the sudden collapse, the induced eddy currents decay exponentially, with a time constant determined by the characteristics of the target. The decay of these induced eddy currents within a target is what we are looking at. Unfortunately the characteristics of the target are not the same, even for a given material ie gold. The characteristics can vary depending on size, shape, density etc and as we know gold nuggets vary widely from solid lumps to speccies to reef gold etc etc. This is one of the reasons that discrimination is so difficult on a PI machine. Hopefully that makes it a little clearer. regards Pat [/QUOTE]
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Gold Prospecting
Metal Detecting for Gold
Idea For Creating Test Nuggets Of Various Sizes?
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