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Jonathan Porter

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Jonathan Porter last won the day on April 6 2021

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  • Gender
  • Location:
    Clermont, QLD, Australia
  • Gear In Use:
    GPZ 7000, ZSearch17x13, ZSearch12, GPX 6000, Xceed 16x10, Xceed 12x7, SDC 2300, GM 1000, EQX800

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  1. You mean coming to terms with multiple close family members passing away from Covid, then getting Covid themselves, whilst trying to run a business? All the while working stupidly long hours with a back injury! I think it’s pretty well established the GPX 6000 pushes PI to the very edge and as such the tolerances on everything associated with it are extremely tight, subsequently very simple things during manufacture can have a big impact on the product. NF set the bar extremely high with their products and honour their warranties (THAT is NOT saying other manufacturers don’t BTW). Minelab do the same but still things go wrong and they have an army of engineers to work on solutions. The 12x7 is popular because of that bar being set very high and creating a differentiation. From NF’s POV the aim was to push the manual sensitivity control as high as possible, the higher you can get that manual control the more information you can get from edge of detection targets and the quieter the experience is for the operator, so the 12x7 coil was designed from the ground up to do exactly that. I know because I had many discussions with NF about this very subject throughout the design process, including carrying that over to the 16x10 when it becomes available. To achieve this required huge amounts of R&D and field testing, people on the outside only see the release dates being pushed back they don’t see the agony of the constant hurdles being thrown in the way as one niggle is sorted to then discover another. Yes it’s not a good look and it’s not ideal and customers are frustrated and impatient, but unless the coil meets the standards it will not be released. Every coil that leaves the factory has to be exactly the same as the others as possible or it’s a fail and even then things can go wrong. I don’t speak for NF but I do know a lot of the backstory and the stress and toll it’s taken to get the 12x7 Xceed to where it is today, that coil is a testament to Rohans determination to get things right. Sure the situation isn’t ideal and I get that I’m often chided for backing companies against the little guy, it’s very hard not to when you see and know the full story of what’s involved on a personal level.
  2. Not so sure about my ability to be too technical 😊 but in essence conductive signals are salt signals created by moisture in the ground. Even in the desert there is sub soil moisture and particularly in goldfields because gold weathering from host rock involves a lot of clays being formed. The rocks on the land contain minerals, those minerals get absorbed by water after rain, the water then flows to the sea and evaporates leaving the minerals behind, that is why the earths oceans are salty. During rain events in the goldfields the weathered country also has concentrations of minerals on the surface of the ground this is due to oxidation just like rust on your car, when those concentrated minerals get damp the conductive signal increases dramatically and in some instances to the point that a metal detector is unusable or a coil that can handle conductive signals has to be used (like the DD coil supplied with the GPX6000). When conductive signals are present the response they create masks or hides edge of detection deep signals, the detector also becomes very swing speed dependant so a slow Motion filter becomes problematic (called recovery on a lot of coin machines), the GPZ 7000 has a Motion filter called Ground Smoothing when applied you can hear the threshold becoming more erratic and unstable but depth is lost so I never use it and instead focus on my coil control. Conductive signals are made worse by larger coils, this is because the conductive signal is seen from a very long way away from the coil. In wet conditions you can see this for yourself by lifting/raising the coil from ground height to above your waist, you will hear a loud long drawn out moaning sound as the coil is moved through an arc. So a smaller coil is recommended when the ground is damp which does not help ground coverage when patch hunting in wide open spaces. The other issue is damp mineralised clays, those can have a complicated effect on a metal detector, especially a highly sensitive machine like the GPX 6000, or GPZ 7000. They produce a combination of conductive signals and another effect on micro magnetic particles in the soils which are impossible to ground balance out, these signals can sound very target like both sharp and shallow sounding and also broad and edge of detection deep sounding. The wetter the ground the worse they are. A key to identifying these is coil control and sweep speed. There are a few immutable things about a motion detector, if using a consistent range of motion relative to the depth of a target (that’s the amount of distance the coil needs to be swept relative to the ‘lead in’ and ‘tail out’ positions of a target, basically from the point the threshold starts to change from the left to right and the other point going back the other way from right to left), then two factors have a bearing on a “real” target over a ground generated one. One is the height of the coil relative to target, in other words the closer you get to a target the louder it should get (very dependant on ground effect (for another discussion another day)) and the speed of the sweep. If the range of motion is maintained but the sweep speed is halved then theoretically the target response should effectively double. A conductive target like response will not do this and will get quieter not louder. In other words, in damp conditions slow down. The reason we move the coil is because the detectors are motion detectors (coil needs to move relative to the target to generate a response), the coil movement is all about the receive aspect not the transmit, moving the coil allows you to investigate any weak fields created by a target, the receive coil of the detector needs to move through the field created by the target, these fields will be thousands of times weaker than the transmit so require careful coil control to manifest properly. Hence why it’s so important to have good coil control, being prepared to vary and control the sweep speed and maintain a good range of motion when investigating edge of detection targets. Accurate ground balance, consistent coil height, good range of Motion and constantly tweaking the swing speed are all vital skills for working successfully with a metal detector, especially in conductive areas. You get all these things into alignment and deep targets jump out at you. Hope this helps JP
  3. Biggest issue with going larger coils with an extremely sensitive PI is the conductive signal. Open areas like WA are really bad for conductive signals and will punish an operator if they go too big. You can use a GPX 5000 with a large coil for prospecting which is less prone to conductive signals but then you lose that tiny nugget sensitivity of the GPX6000 which can be the on;y clue to a good patch or gold being in the area. The GPZ7000 has the same limitation which is why NuggetFinder built the Zsearch 17x13, a good compromise between sensitivity and coverage in vast open spaces. I’ve used one of the early proto 16x10 Nugget Finders in WA and found it to be a very nice blend of quiet running and good coverage with very good depth, it’s like a plumped up 12x7 Xceed. It’s still a work in progress and had to be put aside all of last year due to a number of factors. There are only so many hours in a day, the demand for the 12x7 was off the charts and still is by all accounts. JP
  4. I’d say, and this is just my opinion because I actually haven’t discussed the price increases with anyone, but I’d say it’s to do with the Aussie Dollar against the Greenback. Minelab have had no significant price increases in Australia for a long time and have most likely swallowed up the depreciation in our dollars buying power. Considering their main market is largely offshore sales it makes sense they trade in US dollars and that would then flow back to pricing here in OZ. Everything in Australia has gone through the roof since Covid (there’s that word again 😞), fuel is over $2.10 a litre for diesel here in my home town, electricity has gone up 30% pretty much across the board etc etc. It’s just getting harder and harder to run a business without passing on the cost increases to customers. Property prices are still very high even though the RBA has been lifting interest rates constantly to try and control lending ect, but with the crazy high immigration numbers that’s putting massive pressure on rentals and property values. Probably an over simplified, ill informed understanding of the key drivers behind our economy. Not trying to defend Minelab’s decision to increase prices here, but I would say that is the key trigger point for the reason to do so. 😞 Thank heavens Gold is AU$99 a gram, especially with a vacuum cleaner of a machine like the 6000. JP 💸 (Because of inflation I can no longer use just my 2 cents GIF 😂)
  5. I hold the 7000 in air with left elbow balanced on the top of the arm rest strap, holding the handle with my left hand with the coil held flat in air relative to the ground (folded flat against the shaft), then with my right hand I quickly side to side wave the ferrite on a stick over one receive point UNDER the coil (both receives are fine too) to excite the X balance (Ferrite calibration) with the unit in Semi-Auto and Quick-Trak button held in. (I usually wave a bit before triggering QT to listen to how much ferrite signal there is first). Sometimes it pays to release QT and trigger it again a few times to excite the tracker and force the process. When you use this in air method the G balance will be out as it’s balancing to nothing (X and G are both balanced out at the same time when QT is triggered) so once QT is released I bring the coil to the ground and gently pump up and down and will even sweep side to side then up and down to allow the Semi-Auto GB to get the ground balance (G balance) back to accurate. Sometimes if the GB is way out the tracker will lock because of the loud ground signal (called pausing effect, you need this to prevent tracking out a good target at depth), so I’ll just place the coil on the ground and leave it motionless for a few seconds to allow the tracker to unlock, then resume pumping, repeating this till you hear the tracker kick back in and balance out the ground signal. At no stage after this process do I EVER trigger Quick-Trak unless the Ferrite is present. If you want to be particular and OCD like me you can lift the coil in air again after the ground balance is correct and check the ferrite in air without pressing QT to double confirm there is no Ferrite signal. BTW it is OK to have a small amount of Ferrite signal as the ground signal will always be stronger than a tiny bit of residual Ferrite signal. The timings that require the most attention are High Yield Difficult and High Yield Normal especially if you have the Gain up a fair way. The key thing is to get rid of any loud signal coming off the ferrite, if there are loud signals the G balance will try to compensate for them and your ground balance will be inaccurate. I don’t ever use AUTO because if there are conductive signals present (all gold fields have them) or saturation signals (Australia usually has both together, especially after rain events) then the tracker can’t tell them from X signals and will come up with bad numbers, the poor old G tracker will take the brunt of the assault and try and compensate ending up with a lot of false signals and an unhappy user. When using Semi-Auto, the ferrite calibration is linked to the detectors electronics and more particularly the temperature of the electronics. So in winter for instance the detector will be at ambient temperature at the start of the day, from start up it will be dead cold gradually warming to over 45 degrees internally, so the calibration at the start of the session will slowly move away from optimum to operating temperature but the Ferrite balance is locked in Semi-Auto mode once QT is released, so I recommend to check the ferrite calibration after an hour. In warmer weather it hardly changes (minimums of say 18 degrees C to over 40’s), but I check it anyway because I’m OCD as heck about it. 😂 The key is to have no signal off the ferrite. X balance is tied in with the temperature of the electronics, the X balance calibration is locked if Semi-Auto is used. If X is correct (no signal off the Ferrite relative to the electronics temp) then it doesn’t matter how bad the ground is for X no X signal will be heard unless it is extreme like a high X hot rock (magnetic hot rock). Any X signal that is seen by the machine (incorrect X balance for example) can mask or hide a good target signal at depth. X signals get blended in with general detector behaviour and are very hard to isolate, it’s just an extra layer of noise that does not need to be there. The Ferrite represents X, the one Minelab supply is a specific type, so not just any ferrite works. The reason I use the above in-air method and not just putting the ferrite on the ground is because I work in mostly high X and more particularly high Saturation environments. If the ground has high saturation (where the Tx is affected by highly magnetic surface particles) the saturation signal can be boosted/magnified up through the centre of the ferrite more than double the distance from the ground where the saturation would normally be heard, this can trick the X tracker to some extent but also give the impression the X tracker isn’t working in the Semi-Auto mode. In such cases no amount of ferrite balancing will get rid of the signal as it is a magnified saturation signal you are hearing not the Ferrite, this magnified saturation signal prevents you from getting the coil right onto the ferrite for best calibration practices. Such scenarios can be very confusing and damage confidence. So for peace of mind I just do it in air to get the best calibration possible. NOTE: You can place the ferrite on a large rock away from saturation signals if you have no stick or left the stick at the car. The key here is being informed, knowledge is power. Once you know what something is, then you’re empowered to do something about it or ignore it. That is the mantra of all my training sessions, informing and empowering. Hope this helps JP
  6. Think of it like this, the Difficult timing is a pure “Smooth” type timing whereas the Normal timing is an even blend of both simultaneously. As far as I can tell the vast majority of the target signal associated with tiny nuggets comes from the “Difficult” part of the duality in Normal mode. Non ferrous are the best targets too test on, ferrous will always behave in a differing manner due to having a magnetic component to them. The point to all this is to encourage people to have faith in Difficult/Smooth, especially in areas where Normal can be used like the US but where hot rocks are prevalent and more especially where the ground is shallow and the gold small, in ground like that there’s usually no need to go to Normal unless there’s a chance of deeper larger pieces. JP
  7. All the small target sensitivity comes from the “Difficult” part of the Normal/Difficult combination of the Normal timings mode. If the target signal sounds louder its because the Normal part of the timing is also seeing the target assuming the ground signal does not drown everything out.
  8. Hi Gerry, thanks for the kind words. I too was on the fence when it came to seemingly oversimplifying a detector but the sales and facts speak for themselves. The GM 1000 was an all time best seller for Minelab and still is selling well. The GPX 6000 is also extremely popular and gaining more and more popularity every day as the COVID and other release gremlin’s get ironed out and people learn to trust what it can do and appreciate the benefits. I don’t say these things lightly. The 6000 does not require huge experience to be used effectively, it is simple enough that a pretty inexperienced user can go find some gold even in the harshest ground types. Too many controls can bamboozle even an experienced operator because so much of metal detecting has to do with your mind. You introduce too many variables and it kills confidence, that your settings are wrong or someone is not telling you the “secret” combination. I used the proto Axiom in some pretty bad ground and I tried all the various settings combinations to try and get some advantage out of the “features” and I found myself just coming back to the same settings over and over again. The biggest advantage I found in the short time I used them was getting the threshold pitch and threshold correct on edge of detection gold. Probably the most confusing thing about the 6000 is pairing the bluetooth and accidentally pressing the soils button and then trying to use Normal timings in Hot ground. Those two are the biggest newby mistakes. I agree about the shaft being round but it honestly doesn’t worry me, I have my lower rod super tight and never undo it day to day and only ever shorten the mid shaft when I pack up and head to another location. Getting back on topic, using the GPZ 7000 and Nugget Finder Zsearch 12 combo I rarely change my settings from one day to the next (a little like the 6000). I actually change my sensitivity all the time on the 6000 dependent on ground whereas the 7000 is pretty much set and forget. Threshold 27 Theshold Pitch 40 Sensitivity 12 Audio Smoothing OFF Ground Balance Semi-Auto Ground Smoothing OFF Timings High Yield Ground Type Difficult I go out day after day after day using those exact same settings, the only thing I do from one session to another is check for EMI and do a manual Noise Cancel if necessary, then perform a Ferrite Balance under the coil IN-AIR in Semi Auto mode using Quick-Trak (I have my ferrite taped on a stick) and then pump the coil over the ground with no Quick-Trak then get detecting. That’s how I train people as well. Obviously in soils that can handle Normal you can go from one to the other, but from a newbie POV it is better to stick to Difficult till they learn the basics and develop some muscle memory (coil control, eye, hand, hearing symmetry). JP
  9. There’s a key comment here that tells you a bit about what’s going on under the hood in Auto+. That is a sure sign the ‘gain’ has been increased over manual mode. Manual mode on the 6000 behaves differently compared to a traditional Gain or Sensitivity control. As you lower the manual control you notice a gradual settling of the upper flutter in the threshold but sensitivity to near to coil target signals still sound bright and clear just slightly subdued relative to the manual filter* position, which flies in the face of a traditional gain control. In Auto modes there are two things happening simultaneously and they need to be in alignment for best performance which requires careful control from the operator. Or you can just not worry about it and let it do it’s thing when the conditions call for it. As an example ALL stick shift drivers complain about auto gear boxes in 4x4 vehicles, even the later 10 speed designs, they never get it 100% right. For max depth with the 6000 you need to run Max manual sensitivity, that is by far the best detecting scenario IF conditions will allow. This is why I like the new Nugget Finder 12x7 Xceed coils, they were designed from the ground up to work in hot variable soils so run very quiet allowing max manual sensitivity. Max manual sensitivity opens up the sensitivity filter to provide max edge of detection response, once again assuming the conditions will allow it. The NF coils have a natural mellowness to them which then flows through to the end user especially in hot ground. The main aim being opening up the sensitivity “Filter” (*for want of a better term) to get max information through to the end user. In super quiet soils the ground balance has nothing to work against so target sensitivity can actually suffer, suggest operators carry around a mild hot rock and ground balance to that occasionally and see how things go. One of the reasons why I don’t like a full auto GB and prefer to have the ability to FIX the GB. Put the hot rock on a string and throw it down every so often, sweep over it holding the Quik-Trak button in to help keep the GB centred and averaged, give it a try you might get a pleasant surprise. JP
  10. The last few years have been tough on a lot of people and businesses all over the world. That tough will have a flow on effect in economies and peoples lives for a long time to come. In the gold game nothing is ever what it seems and conjecture will almost always lead to getting things wrong which can then lead to supposition and even embellishment dependant on the discourser, the platform and their POV. Take everything you read online with a grain of salt, especially repetitive factoids, very few people have an inside scoop on the truth. Right now there are plenty of quality coil choices for the 6000 with more in the offing and there is absolutely nothing wrong with what comes supplied. The GPX6000 is a fickle highly strung beast that pushes the PI envelope beyond extremes, that’s why it costs the big bucks. To an end user it seems so simple to turn on and go and ping a piece of gold. It would have to be THE most ridiculously easy machine I have ever used in 28 years of field testing. It is light weight, it has minimal simplistic controls, it’s user interface is not complex, it is a field trainers delight, but that’s where the simplicity ends. The underpinning tech is the complete opposite, it is complex and powerful and requires very fine tolerances to get right, it took huge amounts of R&D effort to get it to the finished product. Just my 2 cents worth of opinion JP
  11. Bigger coil equals more EMI and more Conductive signals with more outright depth but less sensitivity (The GPZ19 has a depth advantage from about 1 gram and up relative to the ground conditions and timings used). Conductive signals kill depth. Xtra deep handles conductive signals better thanks to the longer delay. Conductive signals tend to be fast time constant so Xtra Deep will not be good on porous gold or specimen gold which lose their energy really quickly. Solid chunky gold hold onto their energy a lot longer. A larger coil has a greater receive area so will have greater depth and less sensitivity due to less wind’s to get the inductance right this also helps with ground noise. The nuggets pictured are solid and dense, perfect for the longer delay of Xtra Deep to help mitigate the conductive signals. Very impressed with the energy and effort you put into your field work Lunk. 👍 JP
  12. David I’m thrilled your book has finally been realised, I wish you every success but more importantly thanks for sharing with us your very interesting career. This forum has some truly diverse and fascinating people as its members. 😊 JP
  13. Sure you did. 😉 😂 😆 😝 Admit it your a detector collector tragic like the rest of us. 🧐 You’re going to have to become Durga to swing them all. 😂 Durga Born fully grown and beautiful, Durga presents a fierce menacing form to her enemies. She is usually depicted riding a lion and with 8 or 10 arms, each holding the special weapon (detector) of one of the gods (Minelab, Garrett etc), who gave them to her for her battle against the buffalo demon (The cupboard).
  14. So this isn’t a high end Minelab machine then Simon, thought you weren’t buying high end Minelab again? 😂
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