Fluffy or compact?

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Easylife
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I wonder what the actual different factor is between detectors that are good on fluffy ground compared to those that are better on more compact ground? I though it may be single frequency compared to SMF but not so sure? :Thinking:
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alloverover
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Every machine I've used is better on settled ground, the less air in the soil the better :thumbsup:
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DaveP
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Easylife wrote: Tue Dec 07, 2021 1:12 am I wonder what the actual different factor is between detectors that are good on fluffy ground compared to those that are better on more compact ground? I though it may be single frequency compared to SMF but not so sure? :Thinking:
I had a quick look at this early this morning over a cuppa - there's loads of research in this area from an interesting field. Going back the agri industry have done plenty of work characterising soils by using electro magnetic induction and response; in short, using the principles of a metal detector without wanting to look for metals. Soil conductivity, electrolyte and water content seem to be large, inter-related variables.That lead me to voids and the problems of mine clearance. Metal mines aren't so difficult but there's extensive work on plastic mines with hardly any metal content - the plastic shell acts more like a void and disrupts the signal around the void. That might be the simple explanation why soil with loads of larger voids perform less well than an air test.
alloverover wrote: Tue Dec 07, 2021 6:23 am Every machine I've used is better on settled ground, the less air in the soil the better :thumbsup:
I think alloverover has the pragmatic and useful for detecting summary but if you want to dig deeper try the mine clearance literature where they are already talking frequencies >150KHz.
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