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Found 227 results

  1. I started this project 2 or 3 years ago (so long I can't remember). Spurred on by recent field experiences and also a recent thread on Equinox settings I've finally finished it. I don't know if it's a completely new idea. I call it a 'test-stand' as opposed to 'test garden' just to distinguish it from the standard test gardens many of you either already have or at least are familiar with. There are other similar variable depth test gardens out there (seen on YouTube). This one has the advantage of continuous depth capability. It also allows 3-d target orientation angle (similar to pitch, roll, yaw of airplane). It's based upon the 30-60-90 triangle (remember that from geometry/trigonometry class in high school?): Here is a sketch which shows how to implement this concept: Shown in the sketch, buried at an angle, is a PVC pipe. A test target can be slid into the pipe a distance 2*d which will result in it being located at depth d. I used two sections of pipe (ID = 1.57 in., OD = 1.90 in.), side-by-side to allow me to put neighboring targets in the ground with some option of how close the two targets are separated. Think of this as burying a double barrel (side-by-side) shotgun with the stock end deep in the ground. All you see are the ends of the two barrels. The concrete (bag of Kwicrete) locks the pipes in place. Here's a closeup of those extruding barrels: Besides the tape measure (units of inches) you also see a hand-graded scale at left which I'll explain shortly. Here is an overall view: The two PVC caps, attached together, are for keeping water, dirt, and varmints out of the pipes when not in use. You'll notice a 1.5 in. diameter wooden dowel rod inserted into one of the pipes. More detail on that shortly, but the target is inserted into the dowel near its end and then the dowel is slid into the pipe. Holes for locating pins (you can see one of those -- gray plastic -- inserted to register the intended depth) are 1 inch apart leading to a depth resolution of 1/2 inch. (Again, refer to the 30-60-90 diagram to understand the relationship between insertion length and actual depth into the ground -- a 2::1 ratio.) Next I show the business end of the dowel rod: The black foam fills the chamber and holds the target (in this case a silver dime) in place. The hole in the dowel is actually lined with a plastic film canister (remember those from 35 mm film days?) which has been modified to conform to the circular cross-section of the dowel and thus be able to fit into the pipe. The second slightly smaller) large hole was put in there originally for a second target but so far I haven't used it -- likely of limited value. You can see the registration holes. The first one has a red '2' (difficult to see) just above it; the next (representing 2.5" depth) isn't labeled; the third one has a '3'; etc. These represent the resultant depth of the target when a registration pin is put in that hole and then the rod slid into the pipe until the registration pin keeps the dowel from going deeper. Although the chamber packing material can be made up of many materials, I chose ethafoam (polyethylene foam) high quality packing material. You typically find this in higher end electronics packaging such as with desktop computers. More commonly it is white but in this case I used black. I initially cut plugs with hole saw (see next photo) and then trim with a pocket knife as needed to fit the pipe: Ok, so now you're still wondering what that specially graded (homemade 'yardstick') is for. Again, referring back to the 30-60-90 triangle drawing, the 3rd side of the triangle is also related to the depth. It is squareroot of 3 times the depth. (Squareroot of 3 = 1.73.) That yardstick will indicate how far downrange (along the ground surface) that the target is located. This helps when you get an iffy response on your detector and want to confirm or deny that the surface location of the target is consistent with its depth. The units written on the scale are associated with the depth of the target. You can see from the sketch above that the max depth is 15". The largest common US coin that will fit the chamber (with some force...) is a half dollar. I didn't keep track of the cost but it's probably $30 or so, mostly for the PVC pipe and caps and the dowel rods plus a bag of Sacrete. (I'm counting labor as free. 😁) OK, now that I (finally!) finished this test-stand it's time to get busy making measurements. I'll be posting those here on the forum as they become available.
  2. Hi Guys, How many detector brands have Mixed Mode. Thanks in advance.
  3. I’m not so sure if I really have a opinion but maybe each here may . So please let me hear from you on this subject. Thanks! Chuck
  4. Just thought... it would be interesting if the technology ever came about where you could run one detector as either a VLF or a PI (orZVT). What machines would you combine? I would go GPZ and Equinox
  5. Anyone remember the old Popular Science ads? I thought this was a good classic to share. Even though this ad pre-dates me by 6yrs, it puts a smile to my face :)
  6. Yeah well as in inherently curious person, I was wondering when someone will design a smart phone app that makes your smart phone into a virtual metal detector. Might use a coil like the X35 on a carbon fiber shaft bluetooth connected or USB "c" connected. My Galaxy S10 + certainly has more than the processing power and ram required to do the job. Bluetooth headphone capable, gps, you name it. Just thinking again Johnny
  7. See here http://pericles.ipaustralia.gov.au/ols/auspat/applicationDetails.do?applicationNo=2019902673 AU2019901724A0 Filing a patent for an improved metal detector........ Current Assignee Minelab Electronics Pty Ltd Worldwide applications Application AU2019901724A
  8. I do what I can to foster competition that develops alternatives to the all too common 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 metal detector for beach, relic, or gold detecting. These machines all sell for around $700 and weigh 2.5 - 3.9 lbs. Perhaps 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 VLF 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 VLF 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 (discontinued) plus Garrett ATX and the White's TDI models. These detectors are used not just for gold prospecting but also by relic hunters, beach detectorists, and others who face challenges regarding ground mineralization and VLF 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 VLF 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 detecting. 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 gold prospecting for one month, and needed a GBPI detector, considering machines past and present, what would I get 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, 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 way over 4 lbs and sells for slightly over $2000. The price is close enough really but the 7 lb weight is way off. 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 Minelabs. 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 $1049. 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.
  9. I consider myself to be extremely fortunate due to the fact that the entire age of modern metal detecting has taken place over the course of my lifetime. I was too young in the 60's to be one of the many famous names that were there first on the ground with these new toys that go beep. That's good though for me as most of them are gone now and I'm still here. I got my first detector at the true dawn of the modern detecting age when I got my White's Coinmaster 4 in 1972. It was one of the first of the new "TR" machines that were the starting point for what most of us use today. Mine was as basic as a detector gets, no ground balance existed yet or discrimination. Just a couple inches depth and a beep, dig it up. So I have been involved in detecting now for 47 years. I started my business while in high school in 1976, and have been involved in metal detecting pretty much daily ever since. Anyone who followed my online presence starting in 1998 may see a pattern. I have been involved in some top end machines, some VLF, but basically almost every ground balancing PI made has been in my hands at some point. I had a vision in my mind based on my background in computers that told me what was possible and where we were headed. I was particularly incensed when an upstart company from Australia showed up the industry leaders at the time with the world's most powerful gold detecting PI machines. All the more so when I heard White's had a shot at it and passed. I made it my mission to jump on and foster anything that came along that might compete, and so I was involved with the Garrett Infinium, the first U.S. ground balancing PI. I had a lot to do with White's finally producing the TDI. Yet the fact is nobody ever seriously took Minelab on, and finally they won me over because they delivered when the rest just milked us. Minelab has been the sole company at the forefront of this technology since the SD2000 was introduced. All this time I have wanted two things. A vision in my mind of what a VLF could be. And a similar vision regarding a PI. Both those visions basically revolved around something a normal person could use both as regards ergonomics and price, two areas we kept getting bent over on for 20 years. Long story short I am grateful to Minelab for allowing me to be involved in the machine that delivered on my first vision. The Minelab Equinox is the first machine ever that really can do any VLF metal detecting task and do it well. In any one area it may not be "the best" but no one machine delivers across the board like the Equinox. My VLF quest is over. I will use an Equinox as my primary unit until a detector comes along, probably a Minelab, that does what it does but better. No more VLF buy and try for me. Yay! In 2017 I laid out my vision for the PI I wanted. The price was kind of a set the bar high (with a low price) thing so there is a little wiggle room there. But not a lot... the machine price should be something most people can stomach. As far as I am concerned the GPX 4500 sets the standard at $2699 both for performance and price. The TDI wins on ergonomics but loses too much in performance for me. All I really wanted was a GPX performance in an ergonomic package, and we all know it can be done. That is what is so frustrating. It's one thing to introduce new tech but all I want is proven tech packaged right. Garrett has really been a disappointment not putting the ATX in a light box. They can do it but so far have refused. I would have been satisfied with that. Right now I am calling the Australian made QED as being the default winner of my challenge. The rough edges have been smoothed out, and it's got the ergonomics, coil selection, and price all right. I am not going to argue with anyone over performance. Based on what I know it's good enough for me to go find gold and easily beats the TDI and is competitive with GPX. Good enough for me and good job boys. The only niggle is no FCC approval for U.S. sales, no U.S. dealers or service. But by end of 2020 if there is nothing better I will have one anyway. But we have the Fisher Impulse AQ on the verge and a dry land prospecting version promised. I would be crazy not to wait and see what develops there. I sold my GPZ for many reasons, mostly because I was not going to be detecting much this year, but I resolved when I sold it I would wait until my vision appeared. I knew it was close. I decided I can have fun enough with Equinox until that happens. Put as simply as possible I want a reasonably powerful PI packaged like a good VLF that most of us can afford. Something that can get in and out of a small backpack with an hour of labor being involved. So I am tossing down the gauntlet. I have my magic VLF and am looking for a mate for it. Right now QED and Impulse are in the running. And it's up to Minelab, Nokta/Makro, and sure, let's toss Garrett and White's in there also. It's time to deliver as by the end of 2020 I am getting one. I prefer in the spring but if something is one the radar I may wait. By 2021 I will be using something that finally fulfills what this high school kid from Alaska has known would happen someday. And I got to be there and see it all from start to finish. As I said... a very fortunate soul! Interfacion QED PL2 Fisher Impulse AQ
  10. Try a standard Bic plastic ball point pen medium tip - small brass tip with 1mm tungsten carbide ball. Steve Herschbach has used it for years as a standard for testing gold detectors - also easy to stick in the sand and hard to lose. - and, of course available everywhere.Google Steve Herschbach bic pen and read what he has to say about it. It apparently behaves a very low conductive target. It presents in interesting test of the cut-off setting of a detector with iron discrimination - Might ve interesting for MantaHere’s the results one guy got with his nugget detector on various targets (the POINT - lol - is to show how tough a target the pen tip is....)”Bic Pen-3/4" 1/2 Grain (not gram) nugget 1" 1.3 gram nugget 5" . One tenth oz gold coin 8 1/2".. from Finds Technology Forum When I saw this posted the first time I tested some ball point pens from motels I had stayed at. Didn't have a Bic. Pen A(3.5us time constant) pen B(2.2us time constant) pen C(.65us time constant). Saw reply again the other day. Found Dollar General had 10 BiC Round Stic medium pens for a dollar, 1mm tungsten carbide ball. BiC(2.1us time constant). Charts a little less than a 4grain nugget I have. Wondering why test above has BiC pen closer to 1/2grain nugget than a 4grain nugget. Maybe missing I'm something. Thought I would go to the source to ask. The time constant of ball point pens can vary a lot, wondering if the one I used is the same as used in the test above. Does look like a BiC Round Stic medium tip would make a good test target.
  11. There have been higher, like the Compass Yukon at 100Khz. https://www.kellycodetectors.com/catalog/demo-yukon-99b Compass Yukon-B discovers gold, silver, copper, coins-on land, under dirt, snow, rocks, cement, in shallow water. Yukon-B is a T-R balance circuit incorporating both transistors and integrated circuits. Operating at 100kHz-modulated with 250Hz .Batteries commonly available 9v and 1.5 V penlight. 40-50 hours on 9v, 50-60 hours on 1.5v. Coil is waterproof high impact ABS plastic. White for heat reflection. Audio is distinctive tonal quality for optimum ear pick-up Uncomplicated and easy to set up and tune with only 3 knobs; power on/off volume, metal and/or mineral tuning, and indicating light on/off. I wish I had one of these! So cool, so very cool!
  12. Has anyone had any experience with these things? Electromagnetic and magnetic interferences could be extremely annoying when you are looking for that hard to find gold nugget. Most of the noise is picked up by the search coil but a significant level of noise is being picked up as well by the sensitive electronics inside the control box. The control box is made of aluminium therefore the magnetic field easily penetrates it. To prove that, approach a magnet to the right side of your detector when switched on. Millions of less obvious noise signals are interfering with your detector. We have developed this Shield from the best quality material primarily used in sensitive medical and scientific electronics. After years of studying and testing different materials we have found this one ticks all the boxes. I have revisited the places where I've previously cleaned up and found more gold after installing the shield. It is 0.35 mm thick, held firmly around your control box by the armrest and the new improved version with dual layer shielding on the right side is only 175 g! We have tested it on the GPX 5000 with amazing results such as quieter threshold, better GB, resulting in slightly increased depth. The shield allows you to increase the Rx gain by a notch or two without compromising the threshold. Use Inverted Response when hunting for big deep nuggets. https://www.ebay.com.au/itm/MAGNETIC-INTERFERENCE-REDUCER-SHIELD-FOR-MINELAB-GOLD-DETECTORS/232594646908?hash=item3627b8a77c:g:8lEAAOSwYGFU0bvu I noticed it on Ebay today while I was looking for a cover for my GPX. I have noticed I've been able to quieten down my GPX by opening the control box up and scraping some paint away where the shielding touches the casing, on one end they had scraped away paint from one screw point during production, and the other end had no paint scraped away at all by the factory so it's sheilding was basically useless. By scraping paint away from a few areas on each end of the detector I was able to give the GPX a bit of a noticable quieten down. I am sure on later models Minelab would of scraped away more paint but as mine is a very early model made in Australia version this wasn't done.
  13. We've spent a lot of time here lately on whether to X or whether to CoilTek. We don't know if we should Z or Q. We have so many choices we don't know what to do. Make life simple and get the app: This might be easier. Forget the coils and forget the manufacturer. ? https://play.google.com/store/apps/details?id=com.gamma.metaldetector&hl=en_US
  14. The black stone is pure magnetite. The purpose of this prototype is discrimination that can indicates very deep targets such as for digging . So far all very deep targets were missed , as well as non-magnetic targets are indicated by discrimination like magnetic (iron ) . The prototype was tested on sand of pure magnetite and can be used to search for golden nuggets , while at the same time rejects the shallow iron objects . In tests on different soils shows very low soil noises , and almost complete absence of false signals . There is a video with the same prototype in youtube , from October 2018 .
  15. I’ve been hunting a good site using the Deus and Equinox which has nails and small iron mixed in with good targets, some good targets being deep, but near or in the iron. My question is, will a GPX with Iron Discrimination turned up and the smallest DD coil pull out the deeper, non-ferrous items amongst heavy iron? Has anyone had any experience with this? I think for shallow targets the Equinox or Deus works better for shallow targets in this “machine gun iron”, but would like to see what others may have insight on for using the GPX. I’m assuming the fast setting and special soil timing may need to be adjusted as well. Thank you in advance.
  16. Good evening, I’m venturing into the spotlight here with my first post to ask what likely amounts to a novice’s question. It stems from an experience I had about a year ago with finding my largest nugget. The location was in a small creek bed, which had been conveniently cleared of cobbles and overburden down to a small patch of bedrock surrounded by smooth, silty clay by a dredger. Using a GM 1000, I had detected out several small nuggets from within the bedrock cracks that had been exposed, but not properly crevassed by the prior prospector. However, the thick clay surrounding the exposed bedrock had pockets of varying degrees of moisture. This was providing me a bit of challenge since the wetter spots seemed to be behaving just like hot spots. After an extended wrestling match with the wetter signals and the available settings, I gave up. However, by the time the next weekend came around, I just couldn’t get those wet spots out of my mind. With the heat of the summer and record drought conditions, I guessed those spots may have dried just enough to deserve one final pass. Within minutes of returning, I had found a solid, repeatable, 2 bar non-ferrous signal in the deepest clay pocket on the upstream side of the rock. (This exact spot had seemed masked the week before.) Digging 4-5 inches down into the smooth clay I found a “rock” that made my detector sing. Cleaning it off revealed a beautiful 1/3 ozt. nugget. Call it beginner’s luck—because I do. Now for my question. Were those wet spots of clay giving me fits because of greater relative mineralization, heterogeneity of moisture, or VLF technology? Perhaps it was some of each? Part of my curiosity stems from never having used a PI detector. For those of you with plenty of PI experience, do you also struggle with wet spots or mud spots for lack of a better term? And, if so, are certain PI detectors more resistant to the struggle? Thanks for any input you might spare.
  17. I don't know if I'm right on this but I've found my Teknetics T2 to be a good guide to mineralisation at an area, I use its Fe3O4 meter as a guide. Would I be right in using that as a guide?
  18. I believe there is not much more they can squeeze out of VLF technology, even multiple frequency has it's limits and is really only 2 frequencies. Are manufactures better off concentrating on coil design rather than just tweaking an existing design adding a letter or two to the name? After market coils quite often improve a detectors performance, so shouldn't manufactures be looking in this area rather than using the same coil designed years ago? Would like your thoughts
  19. Which metal detectors have the most reliable target ID numbers? Target ID is a function of depth - the deeper the target, the more difficult it is to get a clean target ID as the ground signal interferes. Other items directly adjacent to the desired target can also cause inaccurate numbers. The more conductive the item, the higher the resulting ID number, but also the larger the item the higher the number. Silver is more conductive than gold, so a gold item will give a lower number than the same size silver item. But a very large gold item can give a higher number than a small silver item, so numbers do not identify types of metal. Gold and aluminum read the same and vary in size so to dig one you dig the other. Only mass produced items like coins produce numbers that are more or less the same over the years but a zinc penny will read lower than a copper penny due to the change in composition. In general iron or ferrous targets produce negative numbers or low numbers. Aluminum, gold, and US nickels produce mid-range numbers. And most other US coins produce high numbers. Other countries coins, like Canadian coins with ferrous content, can read all over the place. The scale applied varies according to manufacturer so the number produced by each detector will vary according to the scale used. The 0-100 range for non-ferrous targets is most common but there are others. Minelab employs a dual number system on a 2D scale with thousands of possible numbers, but they are now normalizing the results produced to conform more closely to the linear scale used by other manufacturers. Increasing ground mineralization has a huge effect on the ability to get a good target ID. Ground mineralization is nearly always from iron mineralization, and this tends to make weak targets, whether very small targets or very deep targets, misidentify. The target numbers get dragged lower, and many non-ferrous targets will eventually be identified as iron if buried deep enough. Small non-ferrous readings and iron readings actually overlap. That is why any discrimination at all is particularly risky for gold nugget hunters. If you want target ID numbers to settle down, lower sensitivity and practice consistent coil control. The target number will often vary depending on how well the target is centered and how fast the coil moves. Higher sensitivity settings lead to jumpier numbers as the detectors become less stable at higher levels. The interference from the ground signal increases and interference from outside electrical sources also increases, leading to less stable numbers. Higher frequency detectors are inherently more sensitive and are jumpier. So lean lower frequency for more solid results. Multi frequency detectors act like low frequency detectors and tend to have more solid target numbers due to the ability to analyze a target with different frequencies. Another issue is the number of target categories, or ID segments, or VDIs, or notches, or bins (all names for the same thing) that a detector offers. For instance here are the number of possible target id categories or segments each detector below offers: Fisher CZ-3D = 7 Garrett Ace 250 = 12 Minelab X-Terra 305 = 12 Minelab X-Terra 505 = 19 Minelab X-Terra 705 = 28 Minelab Equinox = 50 Fisher F75 (and many other models) = 99 White's MXT (and many other models) = 190 Minelab CTX 3030 = 1750 Fewer target categories means more possible items get lumped together under a single reading, but that the reading is more stable. Many detectors will tell you the difference between a dime and a quarter. The Fisher CZ assumes you want to dig both so puts them under one segment along with most other coins. People who use detectors with many target numbers usually just watch the numbers jump around and mentally average the results. Some high end detectors can actually do this averaging for you! But I think there is something to be said for owning a detector that simplifies things and offers less possible numbers to start with. The old Fisher CZ method still appeals to me, especially for coin detecting. So do detectors like the Garrett Ace 250 or Minelab X-Terra 505 for the same reason. The problem is that as people strive to dig deeper targets or smaller targets the numbers will always get less reliable. But if you want to have a quiet performing metal detecting with solid, reliable target numbers look more for coin type detectors running at lower frequencies under 10 kHz or at multiple frequencies and possibly consider getting a detector with fewer possible target segments. And with any detector no matter what just back that sensitivity setting off and you will get more reliable target numbers. ads by Amazon... Detectors often use tones to identify targets and often use far fewer tones than indicated by the possible visual target id numbers. The X-Terra 705 for instance can use 28 tones, one for each segment. However, most people find this too busy, and so simple tone schemes of two, three, or four tones may be selected. I think it is instructive that many people often end up ignoring screen readings and hunting by ear, using just a few tones. This ends up just being an ultra basic target id system much like the simpler units offer. Reality is that most people do not need or care about huge numbers of target numbers. For many just three ranges suffice, low tone for iron, mid tone for most gold items, and high tone for most US coins. The meter could do the same thing, but for marketing purposes more is better and so we get sold on detectors with hundreds of possible target ID numbers. Perhaps this is a digital representation of an old analog meter with its nearly infinite range of response but the reality is we do not need that level of differentiation to make a simple dig or no dig decision. Finally, a picture often says it all. Below we have a shot of the White's M6 meter. I like it because the decal below illustrates a lot. You see the possible numerical range of -95 to 95 laid out in the middle. Over it is the simplified iron/gold/silver range. Note the slants where they overlap to indicate the readings really do overlap. Then you get the probable target icons. -95 is noted as "hot rock" because many do read there. The M6 can generate 7 tones depending on the target category. I have added red lines to the image to show where these tones sit in relation to the scale. It breaks down as follows: -95 = 57 Hz (Very Low) Hot Rock -94 to -6 = 128 Hz (Low) Iron Junk -5 to 7 = 145 Hz (Med Low) Gold Earrings, Chains - Foil 8 to 26 = 182 Hz (Medium) Women's Gold Rings/Nickel - Small Pull Tabs 27 to 49 = 259 Hz (Med Hi) Men's Gold Rings - Large Pull Tabs 50 to 70 = 411 Hz (High) Zinc Penny/Indian Head Penny - Screw Caps 71 to 95 = 900 Hz (Very High) Copper Penny/Dime/Quarter/Dollar Note that the screen reading of +14 is noted as being a nickel or ring but it can also be the "beaver tail" part of an aluminum pull tab or the aluminum ring that holds an eraser on a pencil, among other things. The best book ever written on the subject of discrimination is "Taking A Closer Look At Metal Detector Discrimination" by Robert C. Brockett. It is out of print but if you find a copy grab it, assuming the topic interests you. Always remember - when in doubt, dig it out! Your eyes are the best target ID method available.
  20. Would love to get your opinions and feedback on this machine coming to market supposedly soon, and supposedly uses a BT connection from your phone or smart device to control the coil. Similar to Deus, but using a phone or iPod touch etc. as the controller. Believe it's single frequency. Here's a video demo. I've long liked the idea of a setup like this but I thought there were good reasons the major players have not created a machine utilizing a phone or iPod touch this way, so I'm skeptical.
  21. I myself like the looks of screen of my MX Sport but not the weight. It would be great for it to trim some fat off of it. Out of all the ID numbers it has to offer I’d like to be able to notch out one at a time. We all know that different frequencies is better than others depending on what you’re detecting. If I can I’d like it to be multi frequency where I can run in all and single one if I do wish. What I want is a detector that it will do the major part of my detecting. My thing I’m a coin hunter first be it on a beach are around some old homestead . I’ve never been a relic hunter but it would have to offer the same for that person too . I love nugget hunting but it’s just not a lot of gold in Texas but it would be great to have some high frequencies to nugget hunt. I don’t see the need that I should have to buy another detector for what little I do get to nugget hunt. We all different and our wants runs different too.I know too it’s other detectors offer the things I’m wanting from White’s right now but I’d like to see America made on the side. Chuck
  22. I've seen debate about this question over and over. Thanks to Minelab's vague description of their use of Multi-IQ on both machines. I measured both the 800 and the 600 (my backup machine) and can put this to rest. They both output identical spectrums.
  23. I hooked up a sensor coil to pick up the transmit frequencies from my 800. Connected to an audio spectrum analyzer I could see what was being transmitted in all the modes. Surprise, Park 1 uses only a single frequency ~ 15KHz. The amplitudes shown are relative.
  24. Just finished a second day hunting with the new Mirage PI. Short days, I seldom go for more than 2-3 hours, but enough to start learning a new to me machine. Something I notice and wonder about. The 9.5" mono coil appears more sensitive to iron near the edge of the coil, while nonferrous seems to hit harder near the center of the coil. Could that be a thing or am I deluded? If it is a real thing, is it a reliable way to make dig decisions? I could swear I read something somewhere about this, but am no longer sure because I am deluded in general anyway. Anyone got thoughts?
  25. I did a quick recording of items I had going from a small nickel silver bead through a screw cap. Total of 20 items 6" away in both all metal mode and discrim mode with disc at min. It is interesting how you can actually see the different sounds and how they have unique patterns. I plan on redoing the test when I can set up outside. There is a lot of emi here and my audio setup was not tuned so I couldn't hear the threshold through the computer even though it was pretty loud on the detector. The audio was also recorded really hot which I will correct next time. Wonder if digital machines have just flat signals with no variation other than tone and volume? I can't record my Garrett as it has a proprietary audio jack.
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