Proof That Multi Iq Obsolete Other Single Freq Vlf ! In An Easy Test !
While experimenting with my Gold Racer, I think I saw more stable VIDs by raising the coil and scanning perpendicular to magnetic north. There seemed to be a height that was most stable, and scanning perpendicular to magnetic north tended to eliminate oscillation between very low and very high values. It wasn't perfect, but it was suggestive. I'm wondering if anyone else has anything to offer about this.
By Mxt Sniper
I wonder if Minelab will build a dedicated nugget detector in the style of the equinox, but with gpz type technology. This seems to be the way the CZX by Fisher is headed. I think the Equinox will open up many more machines in the same style eventually. I would hope for concentric and dd coils and more power in a lightweight dedicated nugget hunting package.
By Steve Herschbach
A nice summary quote from Tom Dankowski about why Simultaneous Multi Frequency (SMF) is worth consideration over single frequency options...
“SMF's punch through bad dirt better. Hold on to accurate ID's at depth....and in bad dirt....better. Handle EMI better. Genuinely handle wet-salt better..... to include more accurate ID at depth.,.,.,.,.,.,.,., and a host of other rationale/justifications.”
Fisher Intelligence (5th Edition) by Thomas J. Dankowski
By Steve Herschbach
First Texas (Bounty Hunter, Fisher, Teknetics) - last new models Fisher F75+ and Teknetics T2+. Next up a new pulse induction (PI) beach detector. A new digital multifrequency to replace the Fisher CZ3D is long overdue but at this rate we will be lucky to just see the PI before the end of the year.
Garrett - last new model the AT Max. Hard to believe the flagship GTI 2500 has been around since 1999 with no updates. Garrett so far has shown no interest in multifrequency. The most I was hoping for was a lightweight dry land version of the ATX, but so far no sign of that happening either. I doubt we will see anything else from Garrett this year but they could surprise.
Makro - last new models the Multi Kruzer and Gold Kruzer. Makro has mastered single frequency so everyone would like to see what they can do with multifrequency or pulse induction. I expect Makro is done with new models for the year.
Minelab - last new models Equinox 600 and 800. I have no idea what’s up next for detectors but I sure would like to see that small coil for my GPZ 7000. I really don’t expect anything new for the rest of the year besides Equinox accessories.
Nokta - sister company to Makro. Last new detector the Nokta Impact. Up next the Nokta Anfibio.
Tesoro - Who? What?
White’s - last new models the MX7 and TDI SL Special Edition plus the just announced Goldmaster 24K. Hopefully that new tech will eventually see the light. Right now just getting the 24K out the door is job one.
XP - last new products the HF coils for the Deus, with X35 coils and XP Orx due by end of year.
By Steve Herschbach
When I saw a video showing the Makro Gold Racer recovery speed using two nails and a gold ring, it caused me to reflect on the various internet nail tests. Nearly all employ modern round nails, when these items rarely present issues.
The common VDI (visual discrimination scale) puts ferrous items at the low end of the scale, and items with progressively increasing conductivity higher on the scale. The problem is the size of items also matters. Small gold is low on the scale, and the larger the gold, the higher it reads on the scale. A silver quarter reads higher than a silver dime, etc.
All manner of ferrous trash including medium and smaller nails fall where they should when using discrimination and are easily tuned out. The problem is large iron and steel items, and ferrous but non-magnetic materials like stainless steel. Steel plates, large bolts, broken large square nails, axe heads, hammer heads, broken pry bar and pick tips, etc. all tend to read as high conductive targets. Usually it is just the sheer size pushing it higher up the scale.
Detectors also love things with holes, which makes for a perfect target by enabling and enhancing near perfect eddy currents, making items appear larger than they really are. Steel washers and nuts are a big problem in this regard, often reading as non-ferrous targets.
Oddball shapes cause problems, particularly in flat sheet steel. Old rusted cans often separate into irregular shaped flat pieces, and roofing tin (plated steel) and other sheet steel items are my number one nemesis around old camp sites. Bottle caps present a similar issue in modern areas. These items produce complex "sparky" eddy currents with both ferrous and non-ferrous indications. Many thin flat steel items produce remarkably good gold nugget type signals in old camp areas.
Two general tips. Concentric coils often handle ferrous trash better than DD coils. A DD coil is often the culprit when dealing with bottle caps where a concentric coil often makes them easy to identify. Another thing is to use full tones. Many ferrous items are producing both ferrous and non-ferrous tones. Blocking ferrous tones allows only the non-ferrous tone to be heard, giving a clear "dig me" signal. This was the real bane of single tone machines with a simple disc knob to eliminate ferrous objects. You still heard the non-ferrous portion of the signal. Multi tones allows you to hear the dual ferrous/non-ferrous reports from these troublesome items, helping eliminate most of them.
Certain detectors can also show multiple target responses on screen at once, like the White's models featuring the SignaGraph (XLT, DFX, etc.) and CTX with target trace. These displays show target "smearing" that stands out differently from the clean VDI responses produced by most good items. A machine with a simple VDI numeric readout can only show you one number at a time and the only indication you might get is "dancing" numbers that refuse to lock on. Usually though the predominate response overrides and fakes you out. This is where a good high end visual display capable of putting all VDI response on screen simultaneously can really help out.
I have been collecting these odd iron and steel items to practice with and to help me evaluate which machines might do best in ferrous trash. The main thing I wanted to note here is contrived internet videos with common round nails often present a misleading picture. Many machines do very well on nails yet fail miserably on flat steel.