Equinox At 5 Khz For Hoard And Relic Hunting

[Steve Herschbach]

On 1/5/2018 at 10:43 AM, Chase Goldman said:

widespread use of the Deus HF coils were starting to tell us things we did not think applied using conventional MD wisdom.  Namely, that you could be bypassing high conductive targets because they were not being picked up at 14khz but were being picked up at 28khz and above.  Totally against conventional wisdom.

Well, I guess it depends on whose conventional wisdom we are talking about. I find that result to be exactly what I would expect, but maybe that is because small non-ferrous is my specialty.

I think people tend to view the discrimination scale as low conductive at one end and high conductive at the other. That is the way it is always marketed and explained. However, if all a person does is hunt non-ferrous items, there is a more useful way to look at things.

If items are all identical in size, then the discrimination scale does sort itself by conductivity. A nickel reads lower than a dime, for instance. But what if the items are all of similar conductivity? Say lead, gold, aluminum. How does that sort out?

It's actually more about size than conductivity. Small gold, small lead, small aluminum, all read very low on the target id scale. The larger the items get, the higher they read on the target id scale, even though the composition is the same. Surprisingly, this also applies even to silver. Small thin cut silver reads very low.

The reality if you start to think about it is what we are really talking about is detecting small stuff versus large stuff.

And finally, its this simple. High frequencies hit harder on and better sniff out small items. That is why gold nugget hunters employ higher frequency detectors. In or out of trash, a high frequency machine is a higher energy detector that can better induce eddy signals into small conductive items. Low frequencies are lazier both in response and ability to energize small targets.

The reason that low frequencies can penetrate ground better is backwards of what people think. High frequencies not only light up small targets better, but they highlight and enhance ground mineral issues. High frequencies "see" more ground mineralization, and this blinds them at depth. Low frequencies do not energize the ground as much, rendering it less visible to the detector, which still being sufficient to light up and detect larger items at depth. In extreme low mineral ground high frequencies actually punch very deep, but as you increase the mineralization, high frequencies lose depth at a faster rate than low frequencies.

Anyway, I bet if you look at the targets you are finding it is the smaller stuff that was missed before that the higher frequencies are now revealing for you. That is not to say that some large stuff may not show up also, but the strength of all high frequency detectors is in finding small targets. The strength of low frequencies is actually that they are insensitive to really tiny stuff giving them better ground penetration.

High frequency seems magic in this discussion, but the whole thing goes astray in modern trash. The reason the Gold Bug 2 is not used to coin hunt much is that it will pick up every tiny bit of aluminum ever dropped and chopped. In areas where you are basically wanting to recover all non-ferrous targets higher frequencies are great. But get into modern aluminum, and a lower frequency can simply ignore a lot of thin foil that a hot machine will really bang on. For normal coin detecting in parks lower frequencies are quieter on the tiny trash and still great on coins. All this is why 6 - 8 kHz was THE coin hunting frequency for a long time.

Target ID / VDI Numbers For Gold Nuggets And Gold Jewelry

[Chase Goldman]

Thanks, Steve.  In my case, we WERE in a farm field.  Largely devoid of modern trash (though there was some).  The "high conductive silver" items that were being picked up were smaller, older silver dimes and half dimes so that tends to be consistent with what you were saying.  However, in another case a cache of large CW coat buttons was missed at 14 khz but picked up at 28 khz.  They rang up high, I suspect due to their size not composition as they were of course brass mid-conductors.  So I agree with you that HF hits hard on mid-conductors AND on smaller metallic targets (regardless of composition), but the CW button find really had us scratching our heads because these were Larger targets in a relatively close grouping (7x7' square) completely missed when swept by a lower frequency detector. They were picked up at 28 khz.    This is one specific case where I think things are not necessarily holding to convention (don't know why).  But even if I don't know why, I think MultIQ will more than likely alleviate the "misses" regardless of frequency that I described above and that is why I am optimistic.  Thoughts?

[Steve Herschbach]

Ultimately who knows exactly why some things get found and others missed. There are so many variables all we can do is talk generalities, and those have exceptions. Ultimately as much as I like theory and discussing it when I hit the field I am far more practical. It is just kind of a "whatever works" thing and no one detector has a corner on what works. Equinox appeals to me because it packs quite a toolbox of different possibilities in a compact, lightweight package. It will not always be the best choice, but there is enough there to work with I am confident I will not be left wanting very often.

[Chase Goldman]

Whatever works.  Exactly.  I expect the Equinox will fill in those single frequency gaps nicely.

[Guest Tnsharpshooter]

35 minutes ago, Chase Goldman said:

Thanks, Steve.  In my case, we WERE in a farm field.  Largely devoid of modern trash (though there was some).  The "high conductive silver" items that were being picked up were smaller, older silver dimes and half dimes so that tends to be consistent with what you were saying.  However, in another case a cache of large CW coat buttons was missed at 14 khz but picked up at 28 khz.  They rang up high, I suspect due to their size not composition as they were of course brass mid-conductors.  So I agree with you that HF hits hard on mid-conductors AND on smaller metallic targets (regardless of composition), but the CW button find really had us scratching our heads because these were Larger targets in a relatively close grouping (7x7' square) completely missed when swept by a lower frequency detector. They were picked up at 28 khz.    This is one specific case where I think things are not necessarily holding to convention (don't know why).  But even if I don't know why, I think MultIQ will more than likely alleviate the "misses" regardless of frequency that I described above and that is why I am optimistic.  Thoughts?

I will comment here.

I have loads of Deus HF coils (both)  time under my belt based on actual release date.

And we as users may need to be paying attention when using the Equinox as far as single freq vs muti tone.

What I am talking about exactly?

I have noticed many, many times when comparing undisturbed suspect targets (targets did turn out to be nonferrous), where using 28.8khz would allow for more slop in coil approach/position vs the use of 14.4khz with all other settings being the same except ground balance was acquired using both freqs.

So using the higher frequency depending when sweeping give the coil a larger hot spot(alerting position).

If using full tones for example with Deus, 0 disc, using 14.4khz, user gets more out of ideal position for detection iron tone sounds off and a person keeps walking.

So I will be watching how the Equinox does here.

 

[Chase Goldman]

6 minutes ago, Tnsharpshooter said:

I will comment here.

I have loads of Deus HF coils (both)  time under my belt based on actual release date.

And we as users may need to be paying attention when using the Equinox as far as single freq vs muti tone.

What I am talking about exactly?

I have noticed many, many times when comparing undisturbed suspect targets (targets did turn out to be nonferrous), where using 28.8khz would allow for more slop in coil approach/position vs the use of 14.4khz with all other settings being the same except ground balance was acquired using both freqs.

So using the higher frequency depending when sweeping give the coil a larger hot spot(alerting position).

If using full tones for example with Deus, 0 disc, using 14.4khz, user gets more out of ideal position for detection iron tone sounds off and a person keeps walking.

So I will be watching how the Equinox does here.

 

Interesting (if true) and yet kind of bizarre considering you get more target separation at the higher frequency which doesn't entirely make sense to me with a larger sweet spot.  Did you find the sweet spot increased or decreased when you pushed the coil up to 56/74 khz?

[Guest Tnsharpshooter]

23 minutes ago, Chase Goldman said:

Interesting (if true) and yet kind of bizarre considering you get more target separation at the higher frequency which doesn't entirely make sense to me with a larger sweet spot.  Did you find the sweet spot increased or decreased when you pushed the coil up to 56/74 khz?

Well,

It's true as far as I am concerned.

I haven't actually done a great deal of detecting using the highest band on either HF coil for Deus.

Now the why(s) behind.

Only speculation.

Could be conductivy of target.

Could be orientation in conjunction with conductivity.

Soil minerals.

Maskers.

I will comment more on the maskers.

There are far more maskers than actual nails or bits of nails.

Like even smaller, even rust.

Question?

Will all detectors (Vlf) provide audio on all ferrous materials?

Nope.

Things like rust, micro sized iron.

Even a nonferrous (smaller) out of detectors range can cause it to miss a coin below this nonferrous masker.

One number 9 birdshot could hide a 9" deep coin for example.

And your detector gives nothing tonally, or maybe give iron tone on birdshot, hence you walk.

Now, how far off to the side this masker(whatever it is)  is positioned could be a deal maker or breaker depending on detector, detector's coil, or the actual detector's performance used ( and this could be settings dependent).

I encourage you if you haven't to read all my threads/posts on this forum as they are associated with Deus and HF coils.

I will be posting another soon.

 

 

[RustyDetector]

On 1/5/2018 at 11:25 AM, Randy Dee said:

The Equinox fitted with the 15 x 12 inch elliptical Double-D coil will provide maximum depth using the 5kHz Frequency.   This frequency is ideal for hoard hunting in the UK and for relic hunting in USA.

Having some experience with the Nox 800, I do get better depth and more accurate TID numbers on large deep (Michigan) float copper targets at 5 KHz vs MultIQ.

I will need to confirm this in Field 1 mode as it is composed of more of the lower frequencies vs Park 1.  

I am referring to 10 inch diameter or larger targets down 20 inches or more. I suspect that multIQ really shines with smaller targets in trashier environments as in tailings piles. It doesn’t make me happy to say this because now I need to go back and re-detect at several locations. I can’t wait for the 15 coil to come out.

 

 

[Chase Goldman]

 

14 hours ago, RustyDetector said:

Having some experience with the Nox 800, I do get better depth and more accurate TID numbers on large deep (Michigan) float copper targets at 5 KHz vs MultIQ.

I will need to confirm this in Field 1 mode as it is composed of more of the lower frequencies vs Park 1.  

I am referring to 10 inch diameter or larger targets down 20 inches or more. I suspect that multIQ really shines with smaller targets in trashier environments as in tailings piles. It doesn’t make me happy to say this because now I need to go back and re-detect at several locations. I can’t wait for the 15 coil to come out.

 

 

Remember thst since it is a 15x12" elliptical you are not going to get extensive depth over the 11" coil because the depth performance will be primarily driven by the 12" dimension (though as an elliptical it will get slightly more depth than a 12" round). The 15" dimension determines coil swing coverage more than depth.  HTH.

[RustyDetector]

47 minutes ago, Chase Goldman said:

 

Remember thst since it is a 15x12" elliptical you are not going to get extensive depth over the 11" coil because the depth performance will be primarily driven by the 12" dimension (though as an elliptical it will get slightly more depth than a 12" round). The 15" dimension determines coil swing coverage more than depth.  HTH.

Excellent point, and maybe the reason for the delay in MineLab’s release of the large coil. A slight increase in performance may not justify the investment costs in most cases.