Nice chart.
The DFX engineers do some magic with this to make it more user friendly thus the graph and VDI numbers are a little different. Ralph, I think true all metal is the old TR type that does not reject ferrite or refined iron. A true all metal detector does not reject iron in any form, natural, or refined and used the distortion of the signal to induce a signal into the receiver coil.
Once we go to ground balance we then have zero discriminate to refined metals and balance to ferrite. The old CoinMaster5 was not a true all metal detector as it rejected iron minerals. I don't think Minelab has ever manufactured a true all metal detector. The Advantage is a zero discriminate all metal to refined iron with discrimination of ferrite. The true all metal detector have very little depth in iron minerals so what we think of as true all metal is actually zero discriminate. If we then consider TID then it gets a little more complicated.
However, all metal with discrimination to soil minerals and zero discrimination to refined metals is the best I have seen for depth. In my opinion we will get a little better sensitivity and thus more depth with a threshold.
It is hard to get a manufacture to define "true all metal detector".
The DFX engineers do some magic with this to make it more user friendly thus the graph and VDI numbers are a little different. Ralph, I think true all metal is the old TR type that does not reject ferrite or refined iron. A true all metal detector does not reject iron in any form, natural, or refined and used the distortion of the signal to induce a signal into the receiver coil.
Once we go to ground balance we then have zero discriminate to refined metals and balance to ferrite. The old CoinMaster5 was not a true all metal detector as it rejected iron minerals. I don't think Minelab has ever manufactured a true all metal detector. The Advantage is a zero discriminate all metal to refined iron with discrimination of ferrite. The true all metal detector have very little depth in iron minerals so what we think of as true all metal is actually zero discriminate. If we then consider TID then it gets a little more complicated.
However, all metal with discrimination to soil minerals and zero discrimination to refined metals is the best I have seen for depth. In my opinion we will get a little better sensitivity and thus more depth with a threshold.
It is hard to get a manufacture to define "true all metal detector".