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Jin

How Deep Do Today's Detectors Go Compared To Older Technology?

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I agree with Steve about the research and prospecting skills side of things. It's something I spend every day doing. I'm either researching or learning how the old timers looked for gold and how geology plays its part in understanding where to look.

The thing I wanted to know was am I wasting my time detecting areas that were known for deep gold as newer detectors aren't really punching any deeper than the older ones, (sd2000) especially the detectors that were made or modified to get around the government emission laws. I think Reg has answered my question.

Of course, there's the chance in those areas nobody got it all, but I think my time is better spent in areas of less attention as I just haven't had much success in the flogged areas running a large coil.

Last week I was in the exact spot that the prototypes found good gold. Detected all around that immediate area for nothing. Got me thinking maybe there's no gold left, maybe my detecting skills are poor or maybe this gpz4500 just doesn't go as deep as their detectors did. When you don't have years of experience under your belt all you can do is ask, hence the reason for the original post. 

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Jin, you will see many people post that nobody gets it all and that is very true, I have gone over areas that have been used for rallies that have been hammered to death for over 40 years and I still find stuff, With your 4500 it is just a matter of getting the settings right and the right coil and with the right ground conditions you could find what others left behind,

If you are unsure of your skills, carry a note pad and write down your settings and ground condition etc then you will have something to go back too, even after all these years I still log the important things, But don't be afraid to try something new, like settings etc, just because someone gives you their hot settings does not mean they will work for you or where you detect. Knowledge is a major part of it but being able to adapt to the current conditions is a big part of a good prospectors arsenal.

J.

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Going deeper is not the same thing as whether newer detectors can find gold previous detectors missed. Gold that is in theory within range of the earlier models got missed even at shallower depths. Later models exploit weaknesses in earlier models to clean up what was missed. There may exist a sort of “wall” as regards maximum depth but there are many reasons why some large nuggets were missed that are within the max range of various detectors. The GP series and GPX after it not only get better at detecting smaller gold, but offer various “timings” that allow for better operation in ground that was difficult for earlier models to handle. New coils are better than old coils, etc. The GPZ exploits a PI weakness to go after porous, specimen, and ragged, prickly gold that was missed. There are many reasons a newer detector might reveal large nuggets missed in the past that have nothing to do with the theoretical max detection depth limit. If a detector finds a nugget another one misses, even at shallow depth, is it not in effect “going deeper”.

There is also the geologic fact that many patches peter out as they get deeper, and the deep nuggets people assume are there really are not. Many patches did consist of relatively large and shallow gold. The nuggets were easy for early detectors to find, and there is not anything down there deeper to find.

Finally, people walk around and past items for decades. Any small park will generally still give up old coins if detected hard enough, and nugget patches are the same way. There are targets that only reveal if you are exactly over them and swinging from just the right direction.

Add it up and it’s just too much thinking for me. Personally I don’t care how many people have hunted a location before me or what they used. I just always assume they missed something, and that I am going to find it. I love being told about any completely hunted out and dead patch. GPS coordinates cheerfully accepted :smile:

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Very true, one cannot talk about detector depth without taking into consideration other variables, GB advances, different timings, even audio advances, and importantly different operators and who knows in what direction progress will be made in the future. I have a patch that with a lot of time with the PIs especially the SDC, and the Z you will get a few colours but only shallow yet that patch yielded to the A2B onto the GM2 thousands of colours with very few above a gram in weight in bugger all time. No doubt the Monster with time will score a few more there.

Another patch is different and it has yielded gold at depth and I know it will be so for many more years giving up more to tech advances whether  GB advances, different timings or simply depth advances. The Z 19" s magic exploited that and proved it up, if that patch were pushed many more ozs may come to light, but for me I`m content to leave it as is, a top proving ground patch, plus I`ve experienced what pushing returns, mostly not enough to pay for the diesel.

That completely hunted and dead patch will have this old fella on it in a blink if I too get those GPS Coords , Steve.:wink:

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WOW guys....what a great thread. I have too much going through my head right now & not the time to put it down in a post. Will be back on this one. Cheers

JW :smile:

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On 12/1/2017 at 3:38 AM, Steve Herschbach said:

Honest opinions well stated don't need to stir a hornet's nest. It is the various side commentary where things tend to go astray. I am a big fan of dispassionate observation and leave the  rest out.

Same deal with PI in my opinion. The Minelab SD series in the late 1990's hits large deep gold about as far as it can be hit. The SD series was not that hot on small gold but that helped it on big gold since it is insensitive to many ground and hot rock issues also. Every Minelab PI model since has focused on improving threshold stability and sensitivity to small nuggets or tackling specific hot rock/salt issues. The GPZ further exploits PI weakness on porous or specimen gold, but I am not one of those that thinks it offers any significant improvement on large solid, sluggy gold in most normal circumstances.

As far as the big picture goes I think the bulk of the tech maxed out in the 1990's. What has gone on since is refinement and machines targeting specific weak areas of prior machines. But max depth on larger targets is a very tough nut to crack and I honestly don't pay much attention to claims made in that area. I avoid making such claims myself. The gains if any are so small and so target and site dependent it always boils down to opinionated hair splitting arguments - a waste of time.

Steve I strongly disagree. The issue here is two fold;

  • Firstly big nuggets give off big signals, however thanks to the inverse square law, depth tapers off the deeper a target is which then gives a very narrow band of opportunity for the deeper punching machines to find the gold missed by others.
  • Secondly because detectors have progressively become more and more sensitive over the years people tend to focus on the more productive target sizes and neglect the modes and coil sizes best suited for larger nuggets at depth and the skills required to capitalize on this.

In the case of PI the first SD series were on about par with an increase in sensitivity and less holes in the timings, the SD2200D really benefited from having auto GB. GP series machines then benefited from having Dual Voltage which mainly gave an improvement in sensitivity on fast time constant targets but also a corresponding increase in ground noise negating the deeper signal ability if an operator wasn't careful. GPX detectors were basically extensions and improvements on Dual Voltage with the added advantage of "Smooth" timings which really opened up a range of nuggets still atreasonable depth's but hidden by mineralisation and the inability of DD coils to cope in Normal type timings.

In the case of GPZ that's a whole new animal and to be honest I'm VERY surprised by your lack of faith in ZVT tech on large gold, I think this lack of faith comes down to too few opportunities to prove this out thanks to a lack of larger pieces still existing in the field but probably more important your skepticism in my opinion is down to Minelab failing to get the ZVT depth message to market effectively (I doubt if this is even possible). The juxtaposition is because the high frequency stuff stands out so resoundingly on ZVT, producing results for even average users, the real benefits on larger nuggets which take effort, patience and skill in the right areas are being neglected. The GPZ/ZVT tech thrashes PI resoundingly on big gold if your prepared to let go of the high frequency stuff for a bit and go chase the heavy gold.

Steve I hope my comments are not offensive to you, I felt I needed to respond in kind to your level of skepticism. I'm not defending ZVT as a zealot, my strong opinion is based around my experiences with this technology and the many hours of depth testing I've performed. On big gold there is no equal to ZVT, it resoundingly thrashes PI.

JP

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Not at all JP, great stuff, just people expressing opinions. I certainly give a lot of weight to yours! Thanks for posting :smile:

Funny, I never thought of myself as a GPZ skeptic. I have total faith in mine finding gold if I get over it, including large nuggets at depth.

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I love the 4500, I guess these many soil timing are to fill in the holes where certain types of nuggets fall through the net, I kind of hope ML bring out a 5500/6000 because the GPX series have been hugely successful and it would be a shame to phase them out in the end,

J.

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On 12/1/2017 at 12:34 PM, Jin said:

The thing I wanted to know was am I wasting my time detecting areas that were known for deep gold as newer detectors aren't really punching any deeper than the older ones, (sd2000) especially the detectors that were made or modified to get around the government emission laws. I think Reg has answered my question.

Of course, there's the chance in those areas nobody got it all, but I think my time is better spent in areas of less attention as I just haven't had much success in the flogged areas running a large coil.

Last week I was in the exact spot that the prototypes found good gold. Detected all around that immediate area for nothing. Got me thinking maybe there's no gold left, maybe my detecting skills are poor or maybe this gpz4500 just doesn't go as deep as their detectors did. When you don't have years of experience under your belt all you can do is ask, hence the reason for the original post. 

Jin, it can be a bit of a combination of factors which vary between spots. 

The 4500 is well up to the task to find big deep lumps, it's just that people don't really set them up to target big gold. 

In milder/medium mineralisation I'd be using the biggest DD you can get your hands on and Sharp timing.

In hotter soils I'd be using Enhance and a big mono, 19" Evo or 20" NFA or 22" Gold Stalker. 

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Slightly off topic but highlighted by PhaseTech's post - Am I wrong or has there been precious little attention paid to the Sharp timings on the GPX models? That timing is extraordinary if used in the right way in the right environment. I do wish someone who has had experience using it would publish a short note on how it was to work with and their results with it. 

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