How Far Can Coil Technology Go?

[geof_junk]

These are used in MRI machines. The weight ,cost and flex might work with Metal Detectors

 For a state-of-the-art 3 Tesla MRI machine, the price tag to buy one new can reach $3 million.

I remember a few years ago on another forum suggested a spiral coil using a printed circuit board.

 

[phoenix]

I think the sky is the limit. Some of the amazing coil designs we have see in the last couple of years, I imagine it won`t end where coil design is now.

[Norvic]

2 hours ago, geof_junk said:

These are used in MRI machines. The weight ,cost and flex might work with Metal Detectors

 For a state-of-the-art 3 Tesla MRI machine, the price tag to buy one new can reach $3 million.

I remember a few years ago on another forum suggested a spiral coil using a printed circuit board.

 

Hmmmmm, copper conductive filaments are becoming available for 3D printers, and as Phoenix stated the skies the limit, food for thought. With a multi filament printer one may be able to print the conductive coil and its supports in one print, I have been trying to get my head around CAD to no avail, we need a detector user that has CAD skills. Must be one out there.

[geof_junk]

It is a bit hard to see but this coil uses a silver ink (just under the bottom print square)

[Chase Goldman]

6 hours ago, phrunt said:

The spiral windings appear to have put a bit of punch back into the GPX, The DOD design in the GPZ coils is brilliant.  I wonder what they'll come up with next.

I don't think detector manufacturers put enough focus on coils with how important they are to the detector, in most of the VLF's the makers of the detectors have a pretty small range with some substandard like the Fisher 15" coil.  The aftermarket guys often filling the void where possible.    The improvements a good coil can make to a detector are very noticeable.

I agree with you to a certain extent, but the fact remains that with vlf induction balance technology, you can only go so deep.  The coil really doesn't make as big a difference and I suspect manufacturers know this and do not invest a lot of research dollars into their vlf induction balance coil lines as a result.  I do wish there were more choices for for elliptical style coils and concentric coils on the latest crop of vlf detectors and better cross-compatibility of coils across detector lines.  Nokta seems to do the best job on this and I consider the fact that Minelab didn't do this across Vanquish/Equinox almost insulting, especially if it was driven by marketing.  BTW those Fisher F75/Teknetics T2 15" coils were indeed an abomination in terms of both excessive weight and marginal performance gain for that weight penalty.

PI or hybrid (e.g., GPZ) detectors are where coils can make a tremendous difference in depth performance, and if coil weight can be significantly reduced (along with reduction in weight of the electronics package) without sacrificing performance, that would be a tremendous breakthrough.  The problem is that unlike antennas which can get smaller with operating frequency and needing only a single thin conductive loop to function properly (you are transmitting and sensing only the electric far-field signals), metal detecting requires producing and sensing both the electric and magnetic near-field signals, requiring several turns of conductive material to generate the transmitted magnetic field, increasing weight with every turn and since depth performance is primarily a function of the coil footprint independent of operating frequency.

3D printing and additive manufacturing technologies like the process mentioned at the top of the thread are realky taking off, can't wait to see how they might find their way into detector coil manufacturing.  XP really seems to be on the forefront of incorporating modern, automated manufacturing technologies into their plant. 

If you could somehow marry the manufacturing and packaging innovations of XP with the detector tech and signal processing expertise of Minelab and the customer focused product line strategies of Nokta, and the social media presence of Garrett, you might really have the ideal detector manufacturer.  

[Lacky]

4 hours ago, phrunt said:

Conductive silver ink is cool, I've used conductive silver ink pens for trace repair on Xbox's and Computer motherboards.

 

I'm getting the impression you would be a useful neighbor to have.

[klunker]

 Y'all lost me. I'm goin' back to my steel gold pan and wooden sluice box.

[Noah (FL)]

12 hours ago, geof_junk said:

I remember a few years ago on another forum suggested a spiral coil using a printed circuit board.

 

 

 

Tesoro used a printed spiral for the Sand Shark PI coils.