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Found 135 results

  1. Now that I've got your attention ... One interesting alternative I've seen to traditional walkin' 'n swingin' metal detecting is called the Hot Foot Rug. I'm sure many reading this have heard of it. Basically, from the looks of it it's a search coil apparently embedded into a flexible, rectangular carpet-like piece of material measuring from 18" to 6'. The carpet must, of course, be attached to a box, which the user can keep by their side or clip to a belt. The carpet itself can either be attached to a harness and pulled while walking or dragged behind a vehicle, enabling detectorists to cover a lot more ground -- and with less walking required -- than traditional "stick" detecting. The only thing that makes me not even consider buying one is what I consider to be the excessively-high price (then again, in my opinion MOST metal detectors and search coils are way overpriced.) Especially when dragging the carpet behind a vehicle I would assume the user absolutely must use a good set of noise-canceling headphones. I'm very surprised that the device mentioned above is about the only one of its type I've seen for sale. In my opinion -- and especially with so many detectorists being middle-aged and/or retired folks who aren't as mobile as they used to be -- you'd think there'd be quite a variety of such carpet-like search coils available. Does anyone here prospect with such metal-detecting rugs? My main interest is in prospecting for large, deep nuggets and this technique -- especially with my bad knee -- really appeals to me, as the rug search coil can be several feet wide, which dwarfs even the largest traditional round/oval coils. Any feedback or information on such carpet-type detectors would be appreciated.
  2. I was reading the Australian Electronic Gold Prospecting Forum today and noticed a post about detector depth. I was wondering what others think about today's detectors compared to what was available 25 years ago. I read somewhere that (Woody) the guy that does mods to detectors thinks that for outright depth the sd2000 still goes the deepest. I wouldn't know as I've never owned a sd2000 or a gpz7000. Anyway, i found the comments at AEGPF interesting and wonder if anyone here has actually done a depth comparison between the zed and sd2000. Heres the snippet from AEGPF Quote from AEGPF: "The deepest Pi detector ever developed in my opinion was a prototype SD2000 that BC modified for the late Jim Stewart.BC slowed down the clock speed to give a very long pulse and made some other unknown changes to the circuit to cope with higher currents etc. At the time the SD2000 came out BC stated that it was at about 95% of the maximum potential depth that any handheld PI could ever achieve (and still pass emission standards). However, the deepest PI that has ever been made for gold was Corybns detector which detected a nugget of around 10oz? at 3 feet in depth in WA. Somewhere on the forum is a reference to it and I will try and find the link when I have time. "What is interesting is that the deepest nuggets ever detected by a Pi was by a detector used in the early 1980's in WA-Corbyn's wheeled detector! Pictures of it and the depths of some of nuggets he found with it can be seen in Mike Wattones book: Quest for gold.NO Pi detector today could match the depths Corby got on at least one nugget! (4cm nugget at over 36" in mineralized ground)"
  3. Hi, Regarding the VLF detectors.Can someone answer for me what constitutes a VLF with good discrimination?.I feel to discriminate that speed is a factor as well.Otherwise no matter how good,if a target is next to iron it will read off a good hit. The Deus has fast reactivity,so is this now a good discriminator.Between ferrous and non ferrous?. How does this compare to say the Nokta Impact for speed discrimination. Thanks in advance Ash
  4. http://md-hunter.com/new-xp-q-mond-machine-novelty-2018-look-at-that/ Is this for real, why not go with the smart phone?????????
  5. Editors Note: this thread split from http://www.detectorprospector.com/forum/topic/4335-the-reg-wilson-gold-album/ Nice stuff again... I'm having cardiac palpitations seeing all this gold....lol I wonder if you could tell us how your sled was rigged up. That looks nice for some open ground. Keep it coming....
  6. The more I learn (by reading and experience) the more I realize that unmasking is the holy grail future of induction balance (IB) detectors. Dankowski has been emphasizing the issue for years (as your link to a 2000 article shows Dankowski - Beneath The Mask). The sites I hunt are visciously peppered with iron, small and large. That goes for old homesites here in the Midwest and out West, at old abondoned mines, placer sites, and ghost towns. As bad as littering is today, at least we have trash barrels, recycling, refuse collection, and advertising pleas to keep the world a beautiful place. I get the impression that back in the 19th century the thought didn't even occur to them. People can still cherry pick (using strict discrimination) to avoid the trash. If all you're after is recent drops (clad, zinc, and maybe a few pieces of silver jewelry) then go for it. I want old stuff and, as you note, that means dealing with lots of trash. But even careful hunting today is hampered severely by masking. As Tom D.'s report shows, not only don't you hear the good target, sometimes you don't even here the bad ones! How do you know there might be good target being masked if your detector responds as if there is no metal at all within its search field?! It's my impression that masking is just as big of a problem for nugget hunters. Does it just get less attention because most nugget hunting is done with pulse induction (PI) and zero volt transmission (ZVT) technology, which (AFAIK) doesn't offer much discrimination anyway. If you're really going to dig-it-all, including iron, then eventually you're going to find just about every piece of detectable metal within range.
  7. Whats a good detector to try out for diving 20 to 30 feet in rivers in swim holes etc....... Maybe something I could pick up used? I was thinking maybe an Excaliber II or Garrett Infinium?
  8. Hello, Does the coal or carbon block the EM signals? For example if the metal object buried and covered by shield of carbon or coal. Does the metal detector able to penetrate this type of materials.
  9. I think I could show more interest in any of Garrett detectors but in my opinion they try to put too much info in such a small area. They could take a lesson from White's and let it pop up on the screen on what you detected. This looks like what Minelab is doing the same as White's with a big and better display so all has no trouble to see. I don't see myself buying anything from Garrett until they do. White's has some for the same reason I wouldn't buy either. The young will buy the small screen but with a large one the younger and older will buy. So detector companies you want your sales to go up then come out with a larger display. Chuck
  10. I was wondering about this new machine to hit the market and do believe other manufactures are also releasing soon, the same or very similar type of technology.I dont belive it s new.Can we obtain a list of the main players who will be releasing something similar so i may do a comparison.I think Fisher has one but dont think the At Max coming soon is the same.I m asking this as im not 100% tech savy but dont believe Minelab is the first here or by any means the best.In saying that ,this machine looks very sweet indeed.Also last point.In regard to reactivity speed ,where does the AT Max come in.Thanks in advance. Ash
  11. So Steve or somebody explain to me, putting aside higher frequency is more sensitive to tiny objects like gold nuggets. I realize that. Does higher or lower frequencies go deeper? is there any difference for general coin or relic hunting? Would one or the other pick up or let me hear better a deeper fainter signal?
  12. I always have one question in mind which is the best frequency for silver and gold jwellary or treassure hord at the same time i know 7 to 15 khz is for silver relics tressure 15khz to upper is for gold suppose if i find a cannal full of silver and gold jwellary which frequency is best suited for it
  13. Metal Detector Robot

    Looks funny but there is not far between this video and a decent beach detector at least. Just need the digger scoop arm on the back. Kind of like turning a Roomba loose on the beach!
  14. Steve, your a great source for unbiased information. I trust your opinion greatly. Don't fret over what just happened. Many many people view you as a great resource. As you know I have been metal detecting for 30 years. I still consider myself a newbie. However, it is with the same old machine. Back when I purchased my machine we were told it will detect everything, it's a do all machine. I new of prospecting machines, but never knew the difference or seen the demand until I came to this forum. So if you have time, please answer these question. I am going to throw these out as I don't really know how to ask the correct question. What if the difference in a gold machine vs a regular machine? What makes them stand out? I know there is a frequency difference, but what make them stand on when looking for gold? Are they just not tuned for gold?
  15. I got my first metal detector in 1986. It was a White's Coin Master 6000 DI Pro. I bought it because I live near the beach and a friend of mine had a friend who was selling them. I didn't know much about detectors and I used it on the beach in the dry sand only for about 3 years before life happened and I put it away. I didn't get another detector until 2010 and it was a ML 5000. Now that I had it I had to start learning about the desert and more about metal detectors. One of the first things that I 'noticed' about a detector is that you don't have to be directly over a target to hear it. You get a sense for a target by coming close. You get a bigger sense for an aluminum can than you do a quarter for instance. I've searched and searched over the years for a way to describe this near to target sense which is much greater in the 5000 (PI) and the 7000 (ZVT) than with the Coin Master (VLF). Today I was reading an email from Kellyco who is the company that services most Minelabs in the United States. They also sell most other detectors and give advice to their customers. The email that I received led me to a reprint of an article: How Metal Detectors Work Reprinted with permission from Modern Metal Detectors. The full article is here: https://www.kellycodetectors.com/catalog/how-metal-detectors-work#more In that article it uses the term Fringe Area Detection and that gave definition to what I had been trying to describe for years. I had tried to say a coil is like a Nerf ball with many targets off the search area and you are drawn to a target like a moth to a flame. As it turns out this is just 'fringe area detection' which lets us push our detectors to much greater finds. I think you will see how many times we have discussed this part of metal detecting without using this term. The fringe area on my 7000 is larger than the illustration shown. Here is what the article says about fringe area detection: Fringe Area Detection Fringe area detection is a phenomenon of detection, the understanding of which will result in your being able to discover metal targets to the maximum depth capability of any instrument. The detection pattern for a coin may extend, say, one foot below the search coil. The detection pattern for a small jar of coins may extend, perhaps, two feet below the search coil as illustrated in the drawing on the facing page. Within the area of the detection pattern, an unmistakable detector signal is produced. This illustration shows the location and approximate proportional size of the fringe detection area in which faint target signals from around the outer edges of a normal detection pattern can be heard. What about outside the detection pattern? Does detection take place? Yes, but the signals are too weak to be discerned by the operator except in the fringe area around the outer edges of the detection pattern as shown in the drawing above. A good set of headphones is a must, if you desire to hear fringe area signals. The next more important thing, is training in the art of discerning the faint whispers of sound that occur in the fringe area. Skill in fringe area detection can be developed with practice, training, concentration and faith in your ability. Develop fringe area detection ability to a fine art and you are on your way to some great discoveries that many detector operators will miss. The ability to hear fringe area signals results in greatly improved metal detection efficiency and success. Mitchel
  16. Steve, Every since you posted that you lose depth when you ground balance, It is in the back of my mind........ "Ground balancing is a filter and not all that different that the way the discrimination system works. The ground signal or salt signal (or both) are identified and then tuned out. The ground effect is still there, but the detector subtracts it from the overall signal. The key word there is "subtracts". Ground balance methods work by subtracting part of the signal, and all subtractive methods create depth losses of some sort the closer any detected item gets to the "hole" created by subtracting the ground or salt signal. Signals are not perfect but spread over a small range, and so eliminating any signal usually means taking out a small range of signals. " I have always tried to keep my detectors ground balanced while using them.... Now I wonder if I should? Can you put my mind at ease......
  17. If somebody has offered you at option: 1. to reduce the weight of your favourite detector by half 2. to increase its depth by 10% What would you choose?
  18. No, I'm not talking about politics and being a Moveon.org trainer. I'm talking about resistivity detecting. Electrical resistivity tomography From Wikipedia, the free encyclopedia Electrical resistivity tomography (ERT) or electrical resistivity imaging (ERI) is a geophysical technique for imaging sub-surface structures from electrical resistivity measurements made at the surface, or by electrodes in one or more boreholes. If the electrodes are suspended in the boreholes, deeper sections can be investigated. It is closely related to the medical imaging technique electrical impedance tomography (EIT), and mathematically is the same inverse problem. In contrast to medical EIT however ERT is essentially a direct current method. A related geophysical method, induced polarization, measures the transient response. The technique evolved from techniques of electrical prospecting that predate digital computers, where layers or anomalies were sought rather than images. Early work on the mathematical problem in the 1930s assumed a layered medium (see for example Langer, Slichter). Andrey Nikolayevich Tikhonov who is best known for his work on regularization of inverse problems also worked on this problem. He explains in detail how to solve the ERT problem in a simple case of 2-layered medium. During the 1940s he collaborated with geophysicists and without the aid of computers they discovered large deposits of copper. As a result, they were awarded a State Prize of Soviet Union. Andrey Nikolayevich Tikhonov, the "father of ERT" When adequate computers became widely available the inverse problem of ERT could be solved numerically, and the work of Loke and Barker at Birmingham University was among the first such solution, and their approach is still widely used. With the advancement in the field of Electrical Resistivity Tomography (ERT) from 1D to 2D and now-a- days 3D, ERT has explored many fields. The applications of ERT include fault investigation, ground water table investigation, soil moisture content determination and many others. In industrial process imaging ERT can be used in a similar fashion to medical EIT, to image the distribution of conductivity in mixing vessels and pipes. In this context it is usually called Electrical Resistance Tomography, emphasising the quantity that is measured rather than imaged. https://en.wikipedia.org/wiki/Electrical_resistivity_tomography Here is one unit being offered by Kellyco. https://www.kellycodetectors.com/blog/find-gold-resistivity?utm_source=email&utm_medium=BlogBUTTON&utm_content=BlogGoldResistivity&utm_campaign=MSTRBlogGoldResistivity20170624&utm_term=Lead_SuperBowlGiveaway2016 Mitchel
  19. As a rule do the lower vlf frequencies punch deeper than the higher ones, say 4.8 verses 14khz? But what is the trade off? Are some frequencies better for silver coins? How does iron enter into this? Need to understand how this all fits together! Thanks for any and all answers.
  20. Can someone please explain the differences in a PI machine and a VLF machine in layman's terms or point me in a direction on the site if it has already been posted up some where just trying to learn
  21. I know this topic has appeared off and on over the years, but I'd like to better understanding on the theory and principle of using one over the other, ie. depth, and target id and what compromises do I induce. The reason I ask is the new V4 for XP Deus has the ability to set a minus discrimination. It kills the ability to use the "horseshoe" screen for ferrous target ID, but VID numbers are tolerable. What theoretically happens if I set a negative discrimination, but use Notch to handle ordinary ferrous trash?
  22. Can you guys help me to compile a list of all current VLF detectors on the market that will run in a true ALL METAL no/non motion setting as a user defined base mode, not a hold trigger or pinpoint button held type option but a base mode of operation. Much like what the original M Scope Fisher Gold Bug 19 khz unit operated as. I am seeking a VLF unit with least amount of or no discrimination that operates in all metal no motion, ability to turn up gain and sens as well as GB preferred and has ability to add large format aftermarket coil. I believe that the Tesoro Outlaw has all metal no motion mode.
  23. Is Minelab the only one that uses electronic noise cancel feature?? Do they have patents associate with this feature? Would like to see other manufacturers use some thing similar on their detectors. Or a manufacturer should provide actual visual indication of emi levels depending on frequency used to include offsetting. Not have the user have to use their ears to decide or even try comparing on buried targets. Should not be trial and error. And maybe even a system were the operator is warned,,say if emi changes and the current selected frequency is possibly not operating at optimum. I do realize with a coil being swept over the ground, this could be difficult to do.
  24. I am going through one of those periods where I load up a bit on new detectors and let it all sort out. Darwin's Survival Of The Fittest Detectors! This winter a number will not survive and will be looking for new home. This is the only way I have found that works for me. Detectors that serve a good purpose for me get used, others end up sitting. If they sit long enough, they are no longer needed. I have my nugget detecting fairly well sorted out. The GPZ 7000 gets used 90% of the time. I might pull out a VLF for a really trashy place, or for where the gold is smaller than the GPZ can hit (really small!). I do keep a Garrett ATX around to handle salt ground or oddball hot rocks the GPZ has trouble with but those situations have proven quite rare so far. So the GPZ is an obvious keeper. The ATX does double duty as my favorite water hunting machine so there is another. In the land of VLF however it is more complicated. I have this idea that a good selectable frequency detector might really do the trick in replacing two or more other models. The key there however is what I am going to go ahead and call "frequency spread" for lack of a better term. What do I mean by frequency spread? Simply put, the number of kHz between the lowest and highest frequency the detector can operate at. The lowest frequency is basically the "large item" frequency that more easily handles bad ground, and the high frequency is the "small item" frequency that tends to have more issues with mineralized ground or hot rocks. The high frequency option is critical for a person like me who nugget hunts. To really be able to replace machines like the 45 kHz Minelab Gold Monster 1000, 48 kHz White's GMT, 56 kHz Makro Gold Racer, or 71 kHz Fisher Gold Bug 2, the highest frequency option of the detector needs to be 30 kHz or higher or as close to that as is possible. Low frequencies in the single digits are great for coin hunting or very large gold nuggets in bad ground. Frequencies in the teens are a great compromise. Some examples: Nokta Impact 5 kHz, 14 kHz, and 20 kHz (15 kHz lowest to highest) XP DEUS Low Frequency Coil 4 kHz, 8 kHz, 12 kHz, and 18 kHz (14 kHz lowest to highest) Rutus Alter 4.4 kHz to 18 kHz in 0.2 kHz steps (13.6 kHz lowest to highest) White's V3i 2.5 kHz, 7.5 kHz, 22.5 kHz (20 kHz lowest to highest - bonus - runs in multifrequency mode) I am still waiting on the XP DEUS High Frequency Elliptical Coil 14 kHz, 30 kHz, and 81 kHz (67 khz lowest to highest). The XP HF 9" round running at 14 kHz, 30 khz, and 59 khz (45 kHz lowest to highest) is currently available. In theory the White's V3i is a real winner here but I have just never really taken to the V3i as a prospecting detector. I have to be honest and say that so far the Impact floats my boat more in that regard due to its more traditional approach to a detector interface, all metal modes, and ground balancing. The problem with all of them though is they just don't reach high enough to be used both as coin and jewelry machines and yet still be capable of retiring the high frequency nugget detectors. And that is why I am still patiently waiting for that XP Deus V4 high frequency elliptical coil. At 81 kHz (or 59 kHz in 9" round version) the Deus HF coils on paper at least could in theory make the high frequency nugget detectors redundant. I have to admit I still have doubts however. So far dedicated specifically tuned single frequency detectors have always won the day. For a lot of people however, a selectable frequency machine might prove to be "good enough". The downside with the Deus is that to get the deeper seeking lower frequency large coil option you have to wrap up quite a bit of money into two coils. The 9.5" elliptical is just not going to reach real deep due to its small size. I have the 11" round low frequency coil which can run as low as 4 kHz, so together the two coils make a pretty formidable package. The other machines however can run both much smaller and much larger coils, and at considerably less cost than what DEUS coils cost due to each one being a self contained metal detector. It may be that the XP HF 9" round running at 14 kHz, 30 khz, and 59 khz (45 kHz lowest to highest) is the better compromise option for most people than the 5.5" x 9.5" elliptical. The Impact does suit me as far as the way it functions and I like the excellent inexpensive coil selection. It is a shame it weighs twice as much as the DEUS, but that may actually be a benefit when it comes to balancing large coils. Overall at the moment I am really liking the Impact - I just wish the frequency had topped out higher. I really wanted more like 5 - 15 - 30 kHz. Going from 14 kHz to 20 kHz is not quite providing the extra "pop" on tiny gold I would like to see.
  25. I do what I can to foster competition that develops alternatives to the all too common single frequency VLF detector. There are plenty of options out there, but in my opinion they all weigh too much or cost too much. Usually both. I envision people out there with a popular VLF prospecting machine like the Gold Bug Pro, GMT, AT Gold, X-Terra 705, etc. These machines all sell for around $700 and weigh 2.5 - 3.9 lbs. They would like to add a ground balancing PI (GBPI) to what they have. I think that for "normal people" with normal budgets a machine under $2K and under four pounds just makes sense. It would be more than twice what they spent for their VLF, and in this day and age there is no reason why a decent PI should weigh over 4 lbs. To clarify what I am talking about here, I should say that for many people a $700 single frequency detector is a great place to start and in many cases is all a person ever needs. However, there are places where extreme ground mineralization and mineralized rocks (hot rocks) severely impede the performance and use of single frequency detectors. Alternative technology to deal with these conditions has been developed, by far the most familiar being the Minelab ground balancing PI (GBPI) detectors. These differ from common PI detectors by having the ability to ground balance. Other brands have offered the Garrett Infinium and ATX and the White's TDI models. These detectors are used not just for prospecting but also by relic hunters, beach detectorists, and others who face challenges regarding ground mineralization and single frequency detectors. Frankly, in my opinion GBPI technology is largely maxed out. The main room for improvement comes now in better ergonomics at lower prices. This challenge therefore limits detectors to those that weigh under 4 pounds with battery included, and which sell brand new with warranty after discounts for under US$2000. Detectors need not be ground balancing PI models, but must offer similar ability to ignore mineralized ground and hot rocks that trouble single frequency detectors. I am going to rate detectors as to their relative performance using what I call the "Minelab Rating Scale. Details here. 1. Minelab SD 2000 - crude first version, very poor on small gold, excellent on large deep gold 2. Minelab SD 2100 - vastly refined version of SD 2000 3. Minelab SD 2200 (all versions) - adds crude iron disc, ground tracking 4. Minelab GP Extreme - adds greatly improved sensitivity to small gold, overall performance boost. 5. Minelab GP 3000 - Refined GP Extreme 6. Minelab GP 3500 - Greatly refined GP 3000, last and best of analog models 7. Minelab GPX 4000 - First digital interface, rock solid threshold 8. Minelab GPX 4500 - Refined GPX 4000, solid performer 9. Minelab GPX 4800 - Released at same time as GPX 5000 as watered down version 10. Minelab GPX 5000 - Culmination of the series, current pinnacle of GBPI prospecting machine technology. All Minelab models leverage an existing base of over 100 coil options from tiny to huge. I am a very practical person when it comes to prospecting. I know all the existing models and options by all brands very well, perhaps better than almost anyone. This is the way I look at it is this. If I personally were to spend a lot of money to go to Australia for one month, and needed a GBPI detector, considering machines past and present, what would I take and in what order of choice? Put aside concerns of age, warranty, etc. just assume functioning detectors. Here is the issue in a nutshell. On the Minelab scale of one to ten as listed above, I would be generous in rating the White's TDI SL as a 2. Same with the Garrett Infinium which I will mention in passing as it is no longer being made. If I was going to spend a month of my time and a lot of money going on a prospecting trip to Australia, I would choose a TDI in any version over the SD 2000. I might go with a TDI Pro over a SD 2100 but I would have to think real hard about that, and when push comes to shove I would go SD 2100 were it not for the realities of age I said to ignore. A newer TDI Pro might be a better bet than a very old SD 2100 from a reliability standpoint, but again, this would be a tough choice. The TDI SL not really. In my opinion I would be shooting myself in the foot to go on this hypothetical trip with a TDI SL instead of a SD 2100. You see the problem now? The Garrett ATX fares better. I would rate it a 3, roughly analogous to the SD 2200 variants. Still an agonizing choice really and the ATX being new versus SD 2200 being old might again be the tipping point, but from a pure prospecting options perspective the case can be made that the SD 2200 might be the better way to go. The problem for this challenge is the ATX weighs over 4 lbs and sells for over $2000 That's it folks. That is reality. The best of the best that the competition can offer can only go solidly up against models Minelab has not made in years. I am not saying that to be mean or as some kind of Minelab toadie, that is my pure unvarnished opinion as a guy who is pretty well versed on the subject. Let's bring it all home. This person with the $700 machine really, really wants that under 4 lb, under $2K GBPI machine, but if they do their homework they discover that truthfully, they would be better off shopping for a used Minelab than what the competition offers new. With the TDI SL rated as a 2 the ATX in a much lighter box at under $2K is a solid win as a 3. A well designed ATX with standard dry land coils would look very enticing as compared to the GP series Minelab's and with a stronger battery system might rate 4 to 6 on my comparative scale. But Garrett refuses to budge! White's can certainly do something, anything to improve the TDI SL. A battery that lasts all day would be a good start. In the end they are limited by the basic single channel design of the machine. The SD 2000 dual channel design was literally the answer to and the improvement on the single channel technology used in the TDI, the basics of which predate the SD 2000. Still, White's currently owns the under 4 lb under $2K GBPI category so they have the first out of the starting gate advantage. Anything they do would at the very least just show they have not given up. The Minelab MPS patent that formed the basis of the SD series has expired. Not sure about DVT, which formed the basis of the GP series. Where is the competition? What the heck is going on here? Much gnashing of teeth and pulling of hair is going on here, that's what!!! That is my challenge to the manufacturers. Under 4 lbs, under $2K, on the 1-10 scale I am offering, what is the best you can do? The TDI SL as a 2? Really? Yes, really, that is currently the best of the best in the brand new ground balancing PI, full warranty, under 4 lb, under $2k category. You can pick up a 3.5 lb TDI SL right now brand new for $1089. The White's TDI SL takes the crown. Hopefully we will see more competition in this wide open category soon. I have been beating this drum for years to no avail, but I do have reason to believe we are finally going to see more alternatives soon. I hope.