Steve Herschbach

OK, an indirect report from JP at http://golddetecting.4umer.net/t20896-silly-ml#201830 which would indicate that the GPZ may not be the best solution for extreme salt situations at this time.

Be careful what you keep - one mans trash might be another mans fine or jail time!

I am the first to admit there are lots of people smarter than me when it comes to the technical end and especially trying to make sense of patents. They are often very hard to decipher on purpose even for people that know the stuff. What I am saying jasong is I am guessing you have a better handle on it than I do. There is a point where my eyes glaze over and I just focus on what it actually does as opposed to what is under the hood. I think the intricacies of the way detectors work must be every bit or even more fascinating than detecting itself for certain personality types. It seems like most of the really brilliant people on the tech side do little or no detecting. And many of the best detectorists could care less about how the detector performs the magic. It is a rare person that is both a great detectorist and also has a superb grasp on the technology behind it. I think Jonathan Porter is one of those people. Me, I just love prospecting and detecting. Learning the tech and yakking about it is an extension of that for when I can't actually be in the field, and it does help to know a bit about why things work the way they do. But anyone that can read those patents and fully understand them I am in awe of. My brain just does not work like that! Analogies and simplifications work best for me. Simplest one I have heard is that ZVT is like the detecting equivalent of Dolby for audio. The noise is removed so the signal is clearer. I think half of Candy's genius is his melding of audio and detecting technology signal processing techniques as he is proficient in both. EDIT ADDED 3/26/2015 Bruce Candy Technical Paper - GPZ 7000 Zero Voltage Transmission (ZVT) Explained

Letting you? Thank you very much for joining! This is a place for people to have fun and be able to enjoy discussing or even bragging about their detector. Down talk and negative crap people can take elsewhere. There is nothing I hate more when I am detecting than negativism. It is hard enough to keep a positive attitude when it is raining and I am not finding gold without having to listen to somebody bitch. So yes, let's have fun and share the excitement. That is what detecting is all about for me and my wish for everyone here is to experience that also. Every detector I ever get I am the kid at Christmas time with the toy in the box and a big smile. Best of luck to you with your new toy!

The center braided coil or loop is the transmit coil. The two outer coils are both receive coils. I am not sure what benefits if any such a coil would offer on the GPX without the new circuitry behind it. I am guessing these coils are going to be expensive so probably something people will have to pick and choose more carefully. I want a smaller one for sure but would have to think very hard about a larger one. Part of the benefit of having the GPZ is not needing a large coil to get large coil depth. More ground coverage would be my main interest, but these coils are heavier than normal and I am not inlined to put enen more weight out on the end of that rod. The fun part is this really is a new game and it is impossible to predict where the technology will go in the next 5 - 6 years. I would give about anything to know what Bruce Candy is thinking right about now!

Almost all my own use of the GPZ so far I simply let the coil ride on the ground. This introduced a slight amount of noise on the prototype (not sure about new production units yet) but it was acceptable to me. Main thing was it takes weight off letting the ground hold the coil. Works best if there is just a little grass or something to act as a cushion. Main reason is I did not baby coil in the slightest. I had no issues and expects none going forward. If you have seen the insides of most coils and look at the picture above I think we are dealing with a whole different level of precision manufacturing than we have seen previously with PI coils. Compare to the photo below of a Commander 15" x 12" DD. It pinpoints like a mono but small bits sound stronger nearer the two center strips where the windings overlap. That is where you want to use scoop over the top of the coil. Commander 15" x 12" DD Coil GPZ 14" x 13" DOD Coil

Well Fred, it is the Nokta and Makro units that come with the free vibrator!

Actually the blade thing is mostly a marketing myth. Next time you are out in the field move a nugget around under the coil and not the detection area. Something with a little size. Really small nuggets tend to only hit near the windings. But anything with size will reveal that the straight edged blade seen in ads does not exist. I started a thread on the new coil at http://www.detectorprospector.com/forum/topic/670-gpz-14-coil-for-minelab-gpz-7000/ and was surprised by the lack of comments. Short answer is it is like swinging two DD coils next to each other so more like a mono but with two hotter strips.best bet is follow the link and look at the pictures.

The Gold Bug 2 with small coil easliy hits bits under 1/10th grain, but you have to scrub the coil a lot so get a scuff cover. The coil is impervious to hits and knocks so I scrub it around and use it to rake small rubble aside.

Sadly there are many rude and unappreciative people on the Internet. Being anonymous brings out the worst in people. I for one like and very much appreciate the open and forthright path Nokta and Makro have chosen. Illegitimi Non Carborundum. I am sorry the Racer caught me at such a busy time. I was unable to provide much serious feedback early on. Look like I am finally catching up and will have more time to spend with it soon. Thank you Dilek.

Thanks a Rick, but right now I feel more like it is Chris Ralph deserving a medal. He has persevered on the Aussie and other forums where I have retreated. Just too many unappreciative people and I do not have time for it anymore. I guess I burned out and at Dankowskis it got pointed out I seemed to be on edge these days. So I decided to give myself a break and just stay in the walls of my own website. Chris on the other hand seems feistier than ever these days and more power to him.

- Ergonomically, how does the extra weight carry and how does the detector swing compared to a GPX series machine? Answer - The GPZ is very well balanced but a GPX is roughly two pounds lighter on the bungee. No matter how you cut it more weight to man handle in rough terrain. - Will elliptical coils be available for it eventually? Or does the new coil style only work with rounds? Answer - Semi elliptical coils with blunter ends should be no problem but the new coil topography may make very narrow pointy coils difficult if not impossible. My opinion only though. - Will it hit on the infamous types of spongy and specimen gold that are completely invisible to GPX series models Answer - Yes. - Can someone compare a 5000 with a 14" mono VS the GPZ7000 on various target sizes and depths. Minelab sponsored tests with up to 40% performance gains are well and good but there needs to be 3rd party confirmation and test replication. Answer - Not me. Sold my GPX and every coil for it. The words "up to 40%" leave a lot of wiggle room and I appreciate your desire for proof. My bar is not so high. I just need confidence I am using the best tech I can get my hands on and I have that confidence. But sooner or later somebody will do those tests for you and scream if they do not get 40%. Funny how quick "up to" is forgotten. - Not a competition but for reference purposes can someone compare a Gold Bug 2 VS the GPZ7000 on various grainer size gold and various depths? Answer - Nothing matches a Gold Bug 2 for the tiniest gold in low mineral conditions. My is not going anywhere. - Is there any discrimination at all, if not does this ZVT tech lend itself to discrimination in future models or is it like PI in the respect that its almost impossible to create? Answer - No discrimination. I am not well versed enough yet in the underlying tech to answer what the future might hold. We can hope. - Just how good are the noise cancellation improvements over the 5000? Can you stand right under a transmission power line and null out the interference? Answer - Better but I am doubting that scenario. Not the best answers in the world but hope they help.

I am planning some very detailed notes and observations on weights and balances and other details. Unfortunately I have to ask you to patient for a couple days as I am a bit tied up at the moment. It is not front heavy at all if rid set to proper length. Almost perfect balance. It just simply weighs more overall as more weight was needed in back to get proper balance.

Hello Dave and welcome to the forum. And thank you - nice comments go a long way these days.

I got around some crusty salt puddles and such but nothing like a salt flat. There is no specific salt setting so I am curious myself how the unit does on salt flats or salt beaches. The focus has been 100% on prospecting and I never really thought about it until asked recently.

Bruce Candy offered to sell Whites his newly developed technology. Whites figured PI as a niche technology that would never amount to anything so declined. Instead Minelab was formed and that technology became the SD2000. Probably the biggest missed opportunity in the history of metal detecting.

The CTX battery is 7.2v 34Wh and GPZ is 7.2v 72Wh To will try my WM10 but was told there was interference problem with GPZ that neccessitated change.

From Placer Examination - Principles and Practice Technical Bulletin 4 Bureau of Land Management 1969 DRYLAND DREDGE A mechanical washing plant, sometimes of appreciable size, designed to follow a dragline, or other excavator, as the mining cut advances. Some are equipped with trommel-type revolving screens and rock stackers, and are mounted on crawler-type tracks. In other words a mobile washplant.

The new GPZ 14 is a 13" x 14" coil fully waterproof to three feet. It comes with a scuff cover and has its own lower rod section attached. The coil, lower rod, and scuff cover together weigh exactly three pounds. It uses a winding configuration not used in consumer detector models before which facilitates the technology used in the GPZ 7000. There is over 6000 feet of copper wire in each coil! These coils are compatible only with the GPZ 7000. Minelab GPX coils will not work on the GPZ 7000. Minelab GPZ 14 Coil with Lower Rod and Scuff Cover

I will weigh the production coil in a couple days and get back to you on it. I myself am curious about salt water and whether the unit can ground balance into the wet salt range.

I did not encounter any hot rocks the GPZ was unable to handle except for some no detector has been able to handle. I have a chunk of pure magnetite found at some California locations. Over ten pounds of magnetic iron ore. The GPZ failed just like every other detector I have tried on it. A detector that would not detect that would probably not detect gold either but one can always hope so I had to give it a try.

That is the B&Z booster made by JP which I have been using on my SDC 2300 but which I have also been experimenting with on the GPZ. It works but I am not sure yet it added any serious functionality. You can plug booster directly into detector or plug booster into wireless module so there are variations to experiment with. I have to say the wireless is nice. Proprietary no-lag good quality audio.

Hi Scott,I field tested a unit using the same battery as comes on the CTX 3030. This smaller battery only made it about 5 hours. The new units including the one I just got have the new larger production battery which is supposed to run in excess of eight hours. I need to do a run in most conservative settings and a run with absolutely everything jacked up to get an idea of difference myself. Good news is CTX battery makes a great backup. In fact I am personally planning on using a future smaller coil in conjunction with the smaller battery to get the weight down by maybe a pound? Not sure as it will depend on how much weight a smaller coil sheds but a pound seems possible in total with savings with smaller battery. The coil acts like a mono at distance but closer up in hotter in two strips lengthwise longitudinally pretty much where the reinforcement ribs are on top of the housing. Bruce Candy illustrates it well in the video.

The original thread has been updated with links to the newly posted up to date instruction manual on Minelabs website.

Here it is, good stuff as always http://www.minelab.com/aus/treasure-talk/introducing-the-gpz-7000 The only major note I will add is that the High Yield/Normal ground combination can be even more effective in our low mineral ground conditions in the US than the High Yield/Difficult ground combination that JP recommends for most Australian ground. Not all ground here tolerates it but where it works it really works.