Search the Community

Came across a post on Facebook, about this gentleman testing a few aftermarket coils. This really opened my eyes this morning. I was under the impression that the Minelab coils were chipped and no aftermarket coils could be used. If this was the case? Why did they wait so long? The smaller coil would suit my needs just perfectly. http://golddetecting.forumotion.net/t26022-gpz-18-coil-test-report

Hii Good afternoon! would you help me regarding minelab Gpz 7000, whether it can detect other metals like silver, bronze, iron, relics, coins antiques other than gold?

So lately I've been noticing when out detecting with Kiwijw his GPZ will find tiny bits of gold quite deep, that weigh less than a shotgun pellet and after often smaller in size, but appears to miss a majority of the pellets very close to the surface, where most pellets call home but not much of the gold calls home. At this one particular spot we went to the other day I decided I'd just use my Equinox and 6" coil, and he used his GPZ with it's 14x13" coil. I had at least 60 pellets by the end of the day, he had about 15 or so, there was no exact counting but the difference was obvious. We were both on the exact same ground, a patch about 20 meters by 20 meters at most as a guess. We both covered a majority of the same ground, starting at one side each and worked our way over to the other person's side. When I got to his side I was digging pellets like mad, even in his dig holes where he managed to get bits of gold out of like the GPZ hardly noticed the pellets. I was puzzled by this as I was wondering how he found the bit of gold no bigger than a pellet in amongst the 6 pellets I got out of his dig hole. John did mention he often scapes away the surface soil and if the signal continues down he'll dig it thinking it's possibly gold, is this the reason he doesn't get as many pellets or does the quirk go deeper? This has had me stumped for some time and John wasn't sure why he digs less pellets as he is getting gold smaller than a pellet very often with the GPZ but we both put it down to the HF VLF sensitivity. It was seeming like the GPZ just loves gold. I've come to the conclusion from my research this afternoon it's due to coil size more than anything. I found a Treasure Talk on the Minelab site that had the information I had been searching for. Here are the key statements from it that make sense to my dilemma and in red are the key points, We all basically know that large coils detect deeper than small coils. Why is that? The relationship between the size of a coil and the detection depth depends on a number of factors related to both the construction of the coil and the particular target itself. Starting with the coil itself, to compare the relative sensitivity of a large coil to that of a smaller coil, we need to determine the strength of their respective transmitted magnetic fields and the receiver sensitivities. These can be calculated by applying the Biot-Savart law, which describes the magnetic field produced by an electric current. For this, we need the exact geometry of each winding, the number of turns and the size of the wire. Once we chose a shape, the number of turns and the wire size depend upon the constraints we apply to the design. For example, we usually require the inductance and the resistance of the transmit winding to be the same regardless of the size of the coil, such that the transmitter electronics operates optimally with any size coil. This leads to a reduction in the number of turns as a coil gets larger or conversely an increase in turns as a coil gets smaller. Based on this, we can understand that a small coil with more turns creates stronger localised fields, while a large coil creates a field that is weaker in the immediate vicinity of the coil, but decays more slowly with the distance from the coil. Thus, further away from the coils, a larger coil has a stronger field. We now need to consider the target, for example a particular nugget: if we use one coil as a reference, at what depth can we just detect the nugget with it? Once we know this, we can utilise the previously calculated relative sensitivity to determine at what depth we can detect the same nugget with the other coil. Doing this for a range of nuggets, we find that small coils are better suited for very small nuggets near the surface, while the larger coils are better for intermediate and deep nuggets. Is this the reason the GPZ is missing the tiny pellets near the surface but getting bits of gold amazingly deep that are smaller and lighter than a pellet? I have noticed a similar quirk on my GPX 4500 with it's 14x9 EVO coil where it will miss a lot of shotgun pellets but find tiny gold deeper but it doesn't seem as pronounced as the GPZ but again that's an amateur operator vs a professional. I will try emulate this on an air test when I get the chance but I can't run my GPX around my property as there are power lines nearby that it really doesn't like. Are the pellets KiwiJW is getting the ones that have somehow made their way deeper and he's missing the more shallow pellets? I understand John's a very skilled GPZ operator and it could just come down to operator skill levels but if I am getting multiple signals with 4 shotgun pellets and 1 bit of gold all under my coil at once I'd just be confused and dig all 5 things, meaning I'd end up with all the pellets in my pocket also. John seems to manage High Frequency VLF performance out of his GPZ but misses a lot of the downsides of using a HF VLF, the tiny nuggets he can find on that thing and the depth they come from are just mind boggling. It has to be seen to be believed. Any help on clearing up this mind boggling quirk would be appreciated. A big thanks to Phil Beck for the info I've quoted from his Treasure Talk for this post. Here is a link to the entire Treasuretalk https://www.minelab.com/anz/accessories-1/gpz-19-1

Published on Apr 12, 2018 by steelPHASE In this video I talk about the settings on detectors, aiming mainly at the Minelab GPX, SDC and GPZ series. My aim is not to tell you what settings to run, but rather give you the knowledge to make informed decisions on settings out in the goldfields. Now I am no Einstein so I do stumble and fluster in a few spots but I have edited in some text to make things clearer (hopefully).

You have a new brother in the family. Special thanks to each of you that gave me advise on this decision. Extra call out to Brian for checking the Zed out for me in person. Lot of respect for the tight group we have here. Feel free to drop tips and hints in here or pm. I have read so many threads my eyes are bleeding lol. Come on 1 oz Nug. JW looking forward to nugget find sharing with you. Fred low and slow, Check! Nenad hit me up with more of those tips, so I can pay for this thing lol lol.

Ok I am just passing this link on, as I found it of interest I feel others on DP perhaps may be interested. This is the first I`ve heard of such thus have no idea if it is for real but I hope it is so, we want lighter, smaller, even bigger coils for our Zs. and as we`ve experienced, with the aftermarket coils for SD-GPX series, increased finds, why not for the Z? http://golddetecting.forumotion.net/t25940p60-aftermarket-for-gpz

Is there anyone out there who is willing to explain a little more in depth about the Sensitivity setting in the GPZ7000 and how works in relation to the other settings? Or perhaps point me to an existing discussion? I don’t feel I know enough to use it correctly and I know it's obviously important. Thank you in advance. David

Evening, I hope this makes sense. I have a GPZ and an SDC and they seem to work pretty good near power lines. Plenty of auto channels to try and find a quiet one. As these are the only detectors I have ever owned I am wondering if other detectors - older minelab and other brands - are as quiet around power lines? Especially the really big trans-country lines. The reason I ask is that I found a nice looking area today that has been worked 'in the olden days' and in the short time available (20 minutes) this evening I found quite a few shallow rust nuggets, small/nice sounding bits of lead and absolutely no tell tale signs of old detecting holes. All targets were so shallow that a Kmart brand detector could have found them. This is all within about 60 metres of some bloody big power lines. Would I be right in guessing older technology might not have been able to handle the EMI so this could be some new ground? Apart from the flogging it got 100 years ago Thanks, Northeast

This might have already been posted I figured it would be faster to ask. I have a potential client who is thinking of upgrading from a 5000 to a 7000. The concern is his knees and he thinks he'll have both knees replaced next Spring. I know a 5000 can be used with long shaft (I have customers with titanium knees), but the 7000 is a different beast. Anyone know for a fact if it is possible or should he stick with the 5000? It would be nice to hear from those who know from experience and have tried it.

What ground balancing mode does everyone use? Only reason I ask, is I recently saw a video with Johnathan Porter on Facebook, , where he got a faint signal, that ended up being a nugget. He mentions if he was in auto, passing over the target 3-4 times, more than likely the signal would have went away. Now I hunt in auto, and I can't count how many times I've come across a faint target, and it went away after a few swipes of the coil. Now I wonder how much gold I've missed....😢 Dave

I have noticed since I have been detecting in semi auto tracking, at the start of the day when I drop the ferrite ring on the ground, I can never hear the ferrite, but I do the thing with the quick track button anyway. My question is: Once I have set up the detector to the ferrite ring in semi auto tracking, if I NEVER touch the quick track button ever again, and never take the detector out of semi auto, do I ever have to use the ferrite ring again? It seems to me if you dont touch the quick track button in semi auto the detector always has the correct ferrite balance regardless of ground conditions. Dave

What would the difference be on mineralized rocks and hot bedrock between these two detectors? Took out my 3k and had a hard time detecting due to these two factors. Hoping a new 7k would solve that issue. Thanks.

Ok to kick this off i have just purchased a gpz 7000 spent my time with a sd 2000, gpx 4000 and a gpx 5000 all good machines if you ask me! But tryin to get a steady rewiew on a zed and bloody hell there seems to be two sides to this argument, A. The people who are dealers and trying to sell and in that case the thing has been sent from the gods to find gold!! B. Those who cant afford one and use the trusty 5000 and rag it down it doesnt perform aswell bad in hot ground misses nuggets just garbage bla bla What i want to know is a unbiased opinion on this machine from an average prospector like what most of us will be at how effective it is in a variety of ground conditions. Coming from north qld the gold can come in a variety of iron rock and minerialized ground. And also any tips people have come up with while using this machine?

I used the GPZ 7000 in the Summer of 2016 (with yellow ferrite ring) but it had so much ground feedback in my detecting area that I sold it. I found that the ground noise on the GPZ was masking targets over the GPX-5000 running in fine or enhance gold timings. (Damp & salty highly mineralized ground.) Question: Has the latest software update with Locate Patch & Semi-Auto Ground balance helped significantly to handle this type of bad ground feedback? I am considering buying another GPZ 7000 this Summer to try again. Also, I found that the 5000 can match or beat the 7000 on larger chunky gold targets when running the larger coils. (And of course, the GPZ was superior on some specimen gold types vs the 5000.) Here is an air test on a 3 ounce wire gold & quartz nugget below. The 7000 was at maximum sensitivity of 20 with the stock 14" GPZ Coil. (I didn't own the 19" GPZ coil to try in this test.) I mostly ran in Difficult/General or Difficult/High Yield as Normal mode was impossible here, too much ground noise! 3 Ounce Wire Gold Nugget: (air test) GPZ 7000: Difficult/General: 18" Difficult/HY: 18" Difficult/X-Deep: 16" Normal/General: 21" Normal/HY: 23" Normal/X-Deep: 20" Severe: 15" GPX 5000: Fine Gold w/12" NF Round EVO coil: 17" Normal w/12" NF Round EVO coil: 21" Fine Gold w/15" NF Round EVO coil: 18" Normal w/15" NF Round EVO coil: 23" Fine Gold w/19" NF Round EVO coil: 20" Normal w/19" NF Round EVO coil: 25" Fine Gold w/25" NF Round Advantage coil: 20" Normal w/25" NF Round Advantage coil: 26" -Don

What's the current feedback on the GPZ-19 coil? Good to have? Thanks.

Heading to Rye Patch, NV next week with new detector. Very little mineralization out there and far away from any type of EMI. Looking to go as deep as possible. Reading the manual cover-to-cover but thought you all could provide some guidance on the initial settings. Thanks!

Been wearing headphones while detecting for years. Now that we’re running the GPZ I see some respected GPZ users on here that run without them. Would love to ditch the ‘phones... Thoughts?

I`ve been going back and re reading all the stuff I can find that JP has written about the 7000. One of his articles about going for bigger stuff he recommends General/ Difficult over High Yield/Difficult, and for the last few weeks that`s the setting I`ve been using. Still not setting the world on fire but got a funny one yesterday. This piece came through as that lovely electronic warbly signal I like and before I disturbed the ground I tried High Yield and could just barely hear it. Switched back to General and could hear it no probs. It only goes 0.35 g and it amazed me that General would get such a small piece better than High Yield. It was down about 8 or 9" range. This is one of the articles where JP mentions General over High Yield https://www.minelab.com/anz/go-minelabbing/treasure-talk/gpz-19-compared-to-gpz-14-nugget-dig

Just got a new GPZ-7000. Anyone use the GA-10 Guide Arm? Thanks.

I have two WM 12's, purchased the second some time after the getting the first. The second WM, when turned, on will not work without the original being turned on, is this normal? do I need to do something different to make it work like the original?

This has happened for awhile so I thought I would throw it out to the experts. The Wireless Module on my 7000 does two things I don't understand and are probably related. 1. It takes an insanely long time to charge and after a couple of days, it takes another insanely long time to charge. 2. When out detecting it runs out of charge before a day of detecting is over. Any thoughts? Thanks...

Hi all does anybody ground balance there machine as per instructions then leave the machine on the ground with ferrite under the plate ? I did this while i was getting the rest of my gear ready and it really made it quieter , in very hot ground. The machine was sitting there for about 5 to 8 min approximately.

Does anyone think about going back to the first firmware update for the GPZ? Has anyone felt the audio is different and better results were had with the first update? The upgrade works good but I can't seem to get the audio where it used to be even though I wrote the exact settings down. Just curious if someone out there experienced the same thing. No problems finding gold, just doesn't sound right.

I have audio problem with gpz 7000 and has failed to resolve even after updating the software... the problem started on its own and I resolved to update hoping it will go away but this far nothing is coming

I'm just curious if anyone has created an extension cable for the GPZ 7000 coil. I am working in some narrow spots inside my gold mine and I would love to have the control unit in a backpack on my back and just use the coil without the bulk of the detector. Mlgdave