Jonathan Porter

Then it must be to do with the spacing between the windings, its hard to determine this here in Clermont because the ground is so Variable. I’ll ask Al when we next catch up. Will explain some of the saturation issues and also why some gold modes behave differently compared to others.

Is this a Spiral wound coil your talking about Dave or traditional wound DoD? The Spiral wound coils have the Tx spread out really wide and I’d say the Tx is then influencing the Rx during receive.

The Coil would see the connector which would kill depth and sensitivity.

It would pay to regularly check the adapter for connectivity to avoid bricking your machine with continuous shortening and lengthening of the GPZ shaft which then puts huge pressure on the fragile connector joints. I suggested to the Russian he just make a straight cable instead and have it protrude out the bottom shaft when collapsed to avoid this issue. It looks like he is sheathing the leads in heat shrink then wrapping the coil lead around a rod of some kind then heating up with a hot air gun to get the lead to conform to the curly shape, this must add a huge amount of weight to the coil. Even though he has a curly cable it is way stiffer than the Minelab one so does not soak up tension anywhere near as much, this problem is even worse in cold weather. JP

Steve I feel the same way, social media is were its all now perceived to be at. I have a social media presence but I find it too intrusive, you don’t get time to think about things and constantly feel pressured to check in, write up and add content. If your in business your forced to go the Social Media route because that’s were a lot of your customers are but the dynamics are so fluid it requires constant monitoring which is extremely time consuming. The face most people present to social media is completly different to the real world, therefore the energy they require to keep up appearances means there is never clean dialogue. Social Media is just a data miner that seems cheap for people to access lots of people at once but under the hood I feel it is quite sinister. JP

Mia, the prospecting Dog. To her detecting is just walkies all day long. Relegated to accompanying me here at home on our property since being tagged by a snake in 2017 then 2 weeks later getting smacked again! You wouldn’t know it because she’s so fit and active but age is now catching up so afternoon naps are now the norm, for me anyway if she’ll let me. ? JP

I’m now stocking Doohickies if anyone is interested.???

I’ve stopped stocking them, first of all the orders would mostly get misplaced in transit and then the ones that did arrive would vanish off the shelves before I could provide them with owners reflective tape or otherwise?. I’m pretty certain they’ve been getting inside help from missing pens, hair combs and odd socks!!!?

Norvic, this advice might help you. When you go from Semi-Auto to Manual and back again direct from the Ground Balance menu of the GPZ it always suggest the need for Ferrite balancing by playing the Quick-Trak Guide on your screen, to avoid this you can do three things, Turn Guides off in the Guides Menu Use the BACK ARROW button twice to cancel the Guide Preprogram the USER button to Ground Balance Mode If you use the USER button to access the Ground Balance menu the Quick-Trak guide video is not played, there is never any need to use Quick-Trak when going from Manual to Semi-Auto mode, just pump the coil and keep walking. Hope this helps JP

I’m not at liberty to fully discuss because of confidentiality but Dave has always been fully aware of the Ferrite signal issue (because it was the first thing I noticed about the coils with him present) and has deliberately chosen to not be upfront with his customers. JP

I’ll try not to make this personal and I’ll also try to keep on subject but its hard not to when I read these sorts of comments that are clearly written because it seems like the smoke’s cleared. I especially note the bricked GPZ issue was never addressed!! Firstly on both occasions I’ve met with you you have not been using your GPZ anything like what you have just written, I should be pleased because clearly you have taken my advice and also been reading the many posts I’ve made on the subject and taken it on board. Secondly the method described for your X balance is extremely flawed in an attempt to avoid the very serious and OBVIOUS issue of the X coil not balancing on the Ferrite. Your not using a DIFFERENT method, you are using a flawed method to avoid a SERIOUS problem. Not waving the Ferrite over the noisy spot is NOT going to make the problem go away......absolutely astounding you would think it’s OK to describe such a method and not actually acknowledge the issue and in public too! ??? A serious question for readers of this forum, why would it be recommended to push the coil over the Ferrite too and fro along the receive point? Answer, to avoid the Ferrite from coming anywhere near the faulty solder joint inside the coil. Why is this? Because you cannot balance out the Ferrite on that point, this is because the Ferrite makes a HUGE signal that NEVER reduces no matter how hard you try! What happens if the coil goes over anything similar to the Ferrite in the ground? A VERY LOUD signal will result on anything that has any sort of X signal and a variable interference like signal will result from the many tiny X like pebbles in the soils, instability will be very evident on smaller Ferrite like particles. Call it like it is and let the users decide, don’t cloak the advice in plagiarised information, especially when I fully informed of the issue before the coils went on sale, clearly said advice was taken on board in other areas of GPZ use!! Back on track to keep this post fully on piste, MANUAL mode will provide a LOUDER signal response compared to tracking because tracking will remove a small amount of target signal, that is the nature of an auto GB. The GPZ operates smoother in a Tracking G mode because of the DOD design and the way it reacts on an interchange in variable ground types, Tracking G smooths these interchanges out but the user has to be aware it is not infallible, you need to DRIVE it not IT you. In the case of the X coils that make a big signal on the ferrite the only real option is to use Auto Tracking and hope X is not too prevalent in your area. The spot on the coil that reacts to the X signal is always going to be an issue which means in some ground you will need to revert back to your “Butchered GPZ coil” and leave the ranks of the X men!! JP

X is relative to the area you detect, this is why Minelab supply the GPZ with a Ferrite so you can calibrate the detector. If there is no X signal or minimal X signal then there will be minimal effect, however if there is a lot of X signal then an incorrect Ferrite balance will have an effect. Any noise in the audio train that does not need to be there should be removed via calibration, good detecting practices and sensible settings. The operator has a choice and can decide to not bother using the Ferrite (if they do then I highly recommend they use Auto mode), the GPZ will find good gold if the Ferrite balance is out, if X is present then there will be an extra layer of noise that is varying relative to the amount of X signal in the ground but even in high X situations having a poor X balance does not kill off huge amounts of performance. But if you combine, salt signal, saturation signal, poor X balance and EMI, they can remove a lot of target signal compared to another unit that is being used more efficiently. (EDIT: added more clarity) I like Semi-Auto mode because it saves the need to continually place the Ferrite on the ground, compared to using Quick-Trak to get the G balance correct when using Manual mode. I NEVER use QT without the Ferrite present. Ferrite balances prefer a sweep method not a pump method, only use the pump method for G balance in Semi Auto mode. If you are not noticing any real difference between using Auto and no Ferrite and Semi-Auto using the Ferrite then it suggests your ground has minimal X signal. However because X signal is subtle and mixes in with general ground noise feedback my position is to always X balance with the Ferrite and use Semi-Auto mode just to be sure. It take seconds to do and removes any doubt. The percentages of advantage is in the peice of mind in knowing my detector is always optimal no matter what the ground I am working in. JP

In my opinion Auto is only there now in case I break or misplace my Ferrite. If people do not see the point of the Ferrite then I HIGHLY recommend they use the Auto mode to at least give the detector the chance to calibrate the X signal naturally. Auto might be the only way people can use the X coils in areas with a lot of X signal. Absolutely you can detect in MANUAL, I often do and it does provide the maximum depth achievable assuming both X and G are calibrated properly to the former and localised ground balance conditions for the latter. If ambient temperatures are north of 15 Deg C in the morning then usually the X balance does not move very much, I allow an hour for things to settle down electronically, but seriously 30 minutes should be plenty if the ambient is getting above 20 DegC. It only takes seconds to check the Ferrite balance, so long as the residual signal is small then there’s no need to fret. JP

Hi Jasong, apologies for missing some of your questions and thanks for the PM bringing it to my attention. I am not at liberty to answer all questions especially of a technical nature, firstly because of confidentiality and secondly because I’m not qualified to go too deep on those subjects. Not using a Ferrite means you will never know if your X balance is out, relying on Auto means you are relying on the detectors algorithm to find the X balance for you which is OK in soils were X signal is minimal, in Australia this (and Arizona because I have detected there) is not a good thing in my opinion. Using Quick-Trak could potentially exacerbate things because Quick-Trak forces the G and X tracking, if the detector does not get a good look at X signal during this stage the X balance will have to be out. This is not a problem if there is no X signal in your ground which is suggested by your GPZ successes. X balance is needed because no electronics are exactly the same and prefect and no two coils are EXACTLTY the same and perfect, as such there can be slight temperature drift in ZVT allowing X signal to come through. This is especially true with the X coils. The detector in the environment does not always know the difference between Salt signal, Saturation signal and X signal as such it can become confused if too much Salt signal or Saturation signal is present in Auto mode, this then could cause the X balance to no longer be optimal hence the release of the Ferrite to allow the detector to see an optimal X signal, this is why I advocate the use of Semi-Auto and the Ferrite to prevent this from happening, even for low X ground. The first GPZs had a very lively X balance in Auto mode which potentially allowed Salt and Saturation signals to interfere with the X balance, this was later refined in the first update and carries through to today. Salt Ground can also have variable amounts of G and varying amounts of X signals as well as Saturation signals, you the operator cannot always tell mainly due to the Salt signal being so dominant. Having a good Ferrite balance that is fixed to the units operating temperature in this case is best, to avoid the X balance moving away from optimum. If X is not present then there is no issue. If Saturation is not present then there is no issue. Hope this helps JP

Things have changed in those four years Bill, I used to detect totally differently with the GPZ four years ago two. There’s been two upgrades in that time and everyone including Minelab have come to know ZVT tech a lot better. It’s easy to forget the GPZ is a first of its kind metal detector in the world, the complexity in getting the electronics to work in the first place were immense, thanks to Minelab its been achieved. JP

At no stage have I said anyone is crap at anything, I’m just trying to inform and explain. If self doubt slips in that’s not my fault its just the nature of presenting new ideas and concepts. I’ve tried to keep people informed on the facts associated with my experiences with the X coils, this includes the pit falls and why’s of things because people want to know. I did a long post trying to explain and apologise for any offence taken Madtuna but it got kulled out in one of the clean ups, so I offer it again, I apologise if you have taken offence it was not my intention to offend anyone. JP

In layman’s terms Saturation is where the concentrated highly magnetic mineralised pebbles and soils on the surface of the ground throw a field back at the Tx winding causing a small current to pass across the Tx which then manifests as a signal in your ears. You cannot ground balance out Saturation signal, it will always be there no matter what, unless you lower the Sensitivity, change Ground Type mode (EG go from Normal to Difficult) or use a less aggressive Gold mode (EG go from High Yield to General) or worst of all FILTER it OUT by introducing Audio Smoothing. All PI detectors I have ever used Saturate, this is especially so with the new Flat wound coils on GPX machines. All Saturation signals compete with target signals so the operator needs to perfect their swing height manageament to keep the coil right on the cusp between Saturation noise intrusion into the threshold and maximum depth relative to a buried target. Once Saturation noise intrudes the level of noise that is generated adds to the general threshold noise of the detector effectively reducing sensitivity to a buried target (masking in other words). Because the GPZ 7000 runs so quiet (assuming you are using sensible settings) Saturation noise can interfere or reduce sensitivity, a precious commodity gained through the GPZ’s ability to run Zero Stabilizer (Audio Smoothing OFF). If you introduce Audio Smoothing you mask or hide the effects of Saturation and EMI, both of which KILL depth. I think a lot of X coil users are running their detectors this way and are masking or hiding the differences. All X coils that I have used SATURATE much more readily than Minelab coils, more noise equals less performance which is why I was trying so hard to see them improved before they went on sale. JP

Thankyou Northeast, what Ive been saying can seem confusing because I am being asked VERY detailed questions and then trying to give VERY detailed replies. Like I said previously it should take 20 seconds from the machine switching on till your moving off to find your fortune. In our shop we call it the E F G approach, alphabetical so it is easy to remember the order. E for EMI F for Ferrite Balance G for Ground Balance Hope this helps JP

Quick-Trak equals Forced Fast GB on both Ferrite/X Balance and G balance simultaneously, so it is not advised to use Quick-Trak unless the Ferrite is present. In Semi Auto Mode Ferrite/X balance equals Locked Ferrite/X balance but slow tracking G balance, hence why I slowly pump the coil after releasing Quick-Trak and why I continue to pump the coils occasionally during detecting sessions because it is slowly tracking the G balance. In SEMI-AUTO MODE Ferrite/X balance is LOCKED!!! G balance changes often, Ferrite/X balance only changes if any of the following happen, Big temperature change of the electronics when in any mode (Auto, Semi-Auto or Manual), Saturation signal when in Auto Mode, Salt signal when in Auto Mode. When in Semi-Auto Mode Saturation and Salt cannot effect the Ferrite/X balance only the G. When in Manual Mode everything is locked unless Quick-Trak is triggered, however it is strongly advised the Ferrite be present when doing so. I can’t be any clearer on this subject now, hope this makes sense. Remember in SEMI-AUTO MODE the FERRITE balance is LOCKED and can only change if the temperature of the electronics moves or changes a lot. Usually this happens mostly in winter between first start up and about an hour later as the electronics go from dead cold to operating temperature. In SEMI-AUTO MODE ground cannot effect the Ferrite/X balance only the regular G balance. JP

It really isn’t that complicated. Ferrite balance is performed with the Ferrite, Semi-Auto is preferred because then the ferrite balance can’t shift unless the detector temperature shifts. Ferrite balance is not dependant on ground but instead dependant on the detectors temperature, X signal is in the ground in varying degrees, the detector will react to the X signal if the Ferrite balance has not been performed correctly or if the coil generates signals off the Ferrite that cannot be balanced out. If the Ferrite balance is out the resultant X signal will blend with or elevate ground signals potentially causing spurious indefinable signals and generally make the detector noisier to listen to, all of this will affect depth. It takes 20 seconds to perform a GOOD ferrite balance, in Normal Ground Type mode the detector reacts to Ferrite signal much more aggressively as it does with ground signals and salt and saturation signals, as such I HIGHLY recommend using Semi-Auto to avoid these things throwing the Ferrite Calibration out. There will always be a tiny amount of residiual signal off the Ferrite, especially in the very centre most sensitive part of the windings. This is normal behaviour, so long as there is NOT a HUGE or LOUD signal off the Ferrite. JP

Condor, I’m sorry to hear things have turned out bad for you, there’s nothing worse than being in the field a long way from home with equipment failure. Gold prospecting is 90% headspace, keeping that part positive is hard enough when things are going well, being in a foreign land and having big problems really is hard work. Like all good prospectors the world over you just need to dust yourself off, make some changes and do it all over again, hopefully more the wiser next time. If it was easy it would be boring. ? All the best to you, JP

The issue with the X coils is complex and hard to ascertain because of the many variables users are going to encounter. This has been borne out by the varied reports assuming they are all accurate. You have a couple of options I think, you can do the balance with your GPZ14 coil then swap, you can detect in Auto mode and hope for the best, you can use Semi-Auto and make sure you wave the coil over the ferrite where the windings are and not the other section that makes a noise on the ferrite. It might pay to just expose one side of the coil to the Ferrite only around the front or rear area of the coil to avoid the other noisy section. You can find the sections that are problematic by getting the coil away from the ground and just wave the ferrite over the coil finding the points that won’t balance out or make the most noise. I recommend the front part of the coil for Ferrite balancing well forward off the Yoke. Some of the X coils I tested would not fully balance out the ferrite over the windings no matter how hard I tried ( this issue was quite seperate from the big signal off the ferrite point on the coil associated with the mod), these coils were also quite variable in their behaviour in my high X ground. I have probably raising more questions than I’ve answered, I spent a huge amount of time testing these coils when I foolishly believed we were trying to improve the coils to an acceptable level. JP

Hi Rob, I instruct my customers to NOT use Quick Start because of two things, one it resets the GB, secondly it resets the Ferrite Balance and lastly it reverts the settings to FP if you select the “reset all” option. Semi Auto Locks the Ferrite balance once you release the Quick-Trak button, this is especially important in Normal Ground Type Modes because these modes (especially High Yield) produce the loudest response on the Ferrite and also react the strongest to Saturation and Salt signals. This means in Auto Mode the Ferrite balance can be pulled away from optimum even a few feet from where you last performed the Ferrite balance. This is even more obvious with the GPZ19 coil BTW. There is no need to reset everything unless the detector has gone into a state as described in a thread on this forum through running the machine in an environment that causes the GB state to go entirely out of whack. The GPZ remembers the GB and Ferrite settings on switch off so if your detector was running OK on switch off things will be pretty close at the next start up unless the temps are drastically different or the ground condition has drastically changed. Another trick I do if the GB is way out (especially on new machines) is to use Quick-Trak and pump the coil till there is no noise then switch off and restart the detector then perform the Ferrite balance as described. I usually do the Freq Adjust first thing by holding the coil parallel and away from the ground listening to the threshold and adjust either manually or doing an auto tune, once completed and I’m happy with the threshold I then check the GB is reasonable (Quick-Trak and pump if its bad then switch off then on again) then perform the Ferrite balance as described. Remember the Ferrite balance can only change if the detectors electronic change temperature so there is no need to use Auto mode which just adds an extra variable in an already variable environment. Cutting down on the amount of things that can change is a huge advantage, this is why I advocate using Manual GB when checking targets and during digging, less variables equals BETTER outcomes. JP

I too notice this and IMHO its down to you the operator refining you’re swing speed and height as you centralise over the target. GPZ is a lot different when it comes to centering of deep targets due to the dual receive points of the coil, so initially you hear a faint variation, you then bring the coil back in over the zone and this time make slight adjustments to the speed and height of the coil, you will also (because your now concentrating) remove any variation in the lift of the coil at either end of your swings which then removes salt and saturation signals. You will be amazed how much impact there is on fine tuning the swing over a target, in fact you have, all of the above observations are just that, the fine tuning of the swing and speed and height as you ZONE in over the target. JP