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wanderer

Small Nuggets Vs Big Nuggets

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Maybe this is a dumb question  wit regard to PI machines  why is that one machine will excel at small nuggets but can't do so well on bigger nuggets.,  Doesn't make sense to me.  It would seem logical that iit can find small stuff  big stuff should be easy?

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I am sure there are threads on this subject. Good news is, Steve will pass by soon and may have the links. He is good about that.

Wait till you find some nugs don' even show up lol.

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I have a nugget my GPX 4500 can't see, even when it touches the coils, tried using the Coiltek Joey 10x5 mono, the Nugget Finder Evo 14x9 mono and the stock 11" DD.

20180612_102553.jpg.d0815812931f554fe54ec7f11ecfc479.jpg 

It's the lumpy looking one on the right, the one on the left which weighs under half of the lumpy ones weight the coils pick up at more than 10cm.  I think from memory the lumpy invisible nugget on the right is 0.17 grams, and the other one is about 0.07 grams which is easily seen by all but the DD coil.

I must of found the lumpy one with my GM1000.

I'm sure someone who understands PI's better will answer your question, I sure can't ?

 

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1 hour ago, wanderer said:

Maybe this is a dumb question  wit regard to PI machines  why is that one machine will excel at small nuggets but can't do so well on bigger nuggets.,  Doesn't make sense to me.  It would seem logical that iit can find small stuff  big stuff should be easy?

Hi there wanderer. What do you call a small nugget compared to a bigger nugget. How small is small to you? You will need to be a bit more specific on what PI detectors you are referring to & what size coils. eg SDC 2300 & its only coil of 8". The 2300 is going to be limited in depth by the 8" coil but is renowned to be very hot on small gold within the bounds of its 8" coil for bigger deeper gold. Were as a GPX with a larger coil will get bigger gold at depth but may struggle to get the smaller gold, even near the surface. Depends again on how small is small to you. With a GPX, & with most detectors, a small coil is going to be more sensitive on small gold near the surface but struggle at depth even with bigger gold. It does depend on how big the gold is & how deep. Whereas a bigger coil will do better on bigger gold at depth but struggle with smaller gold near the surface & certainly struggle with smaller gold at depth. Coil size versus gold size & depth is always a trade off. This is where the GPX's, GP & SD range of the Minelab PI's come into their own with the multitude of coil sizes & configurations you can chose to use. Each coil size being a game changer. The composition of the gold makes a big difference too. Like a small but solid, dense chunky little bit of gold will hit a lot better than say a piece of the same size that is porous,  spongy, hokey pokey, rough, prickly, hollow reef type gold. Certain detectors do well on the latter type gold than there bigger brothers. The SDC 2300 I believe does well on that kind of gold. Cheers

JW :smile: 

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7 hours ago, wanderer said:

Doesn't make sense to me.  It would seem logical that iit can find small stuff  big stuff should be easy?

This is my understanding of why one detector will get bigger deeper gold over another.
   A detector transmits a signal into the ground and then switches  to receive the signal coming back to the detector. Think of a opening and closing gate.  The longer the gate is open the further into the ground the signal will travel before the detector switches over to receive the signal. With the likes of the sdc2300 the gate opens and closes very quickly, doesn`t travel into the ground very far, so with the high frequency switching, it will find way more small gold than most other PI`s.  The slower switching detectors, the signal goes way deeper into the ground where there might be a bigger deeper bit.
   I hope I`ve got that right. Please correct me if I am wrong. Dave

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It is simple...if one machine could get it all you would not buy two, or three...etc

I think my GPZ covers most of the ground very well...just teasing a little bit on the above.

fred

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Gotta agree Fred, the Z to me is the detector that comes closest to getting all sizes, specimens, deep, shallow, the works. Of course not right down to those specks the GB2 and now the Monster vacuum. 

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3 hours ago, fredmason said:

It is simple...if one machine could get it all you would not buy two, or three...etc

I think my GPZ covers most of the ground very well...just teasing a little bit on the above.

fred

Fred....Don't be so sensible. :biggrin: You are of course 100% correct. No one detector does it all, & I don't think it ever will. The Zed does do a very very good job on gold though. Just as you said. I have to agree on that.? When it comes to coin & relic detectors that is a whole new ball game with people wanting to cherry pick target signals a lot more, not only to eliminate digging heaps of trash but also being more specific & selective on what targets they are wanting to target & ignore the rest, a lot more than a gold detectorist will. From my humble experience. If I was into coin & relic detecting as well as gold detecting & could only have the one detector I would settle on the Equinox 800. Thats if I didn't want to spend 95% of my time digging rubbish with the Zed. :smile: Otherwise the Zed would do it all for me.

Phoenix, That is a good way of describing the timings. With the 2300 Minelab have pre set how fast you can open & close the gate & so have chosen it to be hotter on the smaller gold & also that prickly, honey comb type reefy gold. Because you can't change the timings & with its one only 8" coil it limits its depth on bigger deeper gold. That is where the other minelab PI detectors just gives the operator so many other choices. You can change the timings by opening & closing the gate quicker or slower :biggrin: There are many settings that are user adjustable & it is that that makes the GP, GPX detectors very daunting to many, initially. The next biggest game changer choices with those detectors is the large array of coils you can select to use depending on what size & depth of gold. Big, small, medium, round, elliptical, DD, mono.....The other settings give you choices depending on what the ground conditions are like & EMI. I don't think we will ever see another range of detectors like those Minelab PI's that gives the user so many choices from the one machine. Good days indeed.

Good luck out there

JW :smile: 

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This all started because i read Steves comparison of the Garret atx to the GPZ 5000.  I was figuring a small nuggets at a gram or less but it is all relative. So why doesn't some one build a  machine that alternates the Gate open close time the way phoenix describes it   cycle on and off  or even better do both simultaneously.  I mean we can build build computers that calculate millions of  data bites is fractions of seconds. We are already bulding robots  that can run  jump walk and move boxes ( see boston robotics and think terminator). is it really that hard?

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My understanding is your wish is basically a Zed, inside its coil looks to be basically 2 coils

post-1-0-73723100-1424317386.jpg

It has that flat wound coil wire in the center which I would imagine it's why it's so sensitive to small gold (along with the software magic in the control box)  then the normal double D coil spaced on the outside, you'll also note the little chip in the middle of the coil, that's why it's been so hard for there to be aftermarket coils for it.

From what I've seen with KiwiJW his Zed is as sensitive as my Gold Bug Pro to small gold, but deeper, and still goes very deep on the bigger stuff.  It's not quite as sensitive as a GM1000 but that could be due to the large size coil on it, as explained in earlier posts, smaller coils are more sensitive to small gold.  A Zed seems like a combo PI + VLF in one unit.

If Minelab were to make a small coil for it, if indeed it's possible, I am sure the Zed would be deadly on small high frequency VLF gold.

Keep in mind these metal detector companies don't have billions of dollars to throw at R&D, the market for them just isn't that big, I'm sure if Google or Microsoft decided to make a detector and threw the kitchen sink at it, things would change rapidly in metal detector technology.  Minelab has done very well financially out of the Equinox however so it's exciting what they'll do next if they put their profits towards R&D.

The Equinox release date was in late January 2018, the Codan (Minelab) share price rose rapidly from February. Made some coin out of my faith in the Equinox ?

Codan (Minelabs parent company) has approximately 380 employees across all of its business ventures located in Australia, New Zealand, Canada, the USA, Ireland, China, the UAE and South Africa, and their profit was 44 million, but a big part of the business is radio communications equipment.

581135422_MinelabSharePrice.png.d50de0b93c44bfd9d2993efc1b0ea3ce.png

You may enjoy reading this if you want to know more about Minelab, it's their 2017 annual report to shareholders

http://codan.com.au/wp-content/uploads/2017/09/Annual-report-final.pdf

Someone with more knowledge on this may want to chime in, but that's layman's my take on it.

 

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