PI for low conductive targets

[Anonymous]

Good morning Bill and Erick,
What would be some of the the design problems for such a machine ?
Could it be possible to "field adjust" to capture better signals from these objects and still remain stable ?
Maybe multiple pulse's of different length for ground balence /target differentiation.
Or maybe "sampling at multiple periods on the same "pulse"
Or different materials for coil constuction (silver,gold,alum or nickel wire,maybe even a room temp. super cond. material)
Russ

 

[Anonymous]

Hi Russ,
I

 

[Anonymous]

Hi Russ,
It is quite possible technically to design PI detectors to locate poorly conductive objects; which also can include very small objects. This is routinely done in industrial PI detectors which can detect ferrous or non-ferrous metal spheres down to 1mm in diameter. These detectors achieve this sensitivity while remaining very stable. As you can imagine, stability is more important in industrial applications than would be the case in treasure hunting. i.e. a whole production line could be stopped, or a valuable product be rejected, if there were a false signal. However, such sensitivities would give serious problems on conductive soil and be unuseable on a wet beach.
Multiple signal sampling is useful as a way of getting more information about the object being detected, although this feature has not yet been fully exploited.
As regards coil construction there is no evidence that exotic wire gives better performance. I use pvc insulated stranded wire, which is adequate for all treasure hunting applications. Stranded wire is better than solid wire as it reduces eddy currents generated in the wire itself, but silver, gold, aluminium or nickel wire will not perform any better than copper. Some persons may disagree for the same reasons that silver, gold etc. wire is supposed to perform better in hi-fi systems but there is no hard objective evidence to support this. Regarding superconducting wire, by its very nature it would not work as the current has to be pulsed.
Eric.

 

[Anonymous]

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[Anonymous]

Hi,Bill What brand of PI and model are you refering to in your example ? Where you using it on any special ground conditions ? esp. wet salt, wet sand,dry land,ect.
Russ

 

[Anonymous]

Russ,
Starting with the Anchor Barracuda, going up a couple of notches to the CScope CS-7, then to Eric