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Found 41 results

  1. The way to go Steve H, I also let it go, no AQ for me anymore they lost me as a client, looking into the Aussie detector QED even without service in the US, when having problems I just send the pot in for service to Down under land, only concern I have is it needs certain adjustment/tuning, for use in gold country in the US what I read. Steve H. Can you tell me what adjustment the QED needs to used in our gold country. I would appreciate any information on this, so I can ask the Aussie maker of the QED to make these ajustments. See this as my experiment for 2020 /2021, I also wouldn't mind to lend my QED as a test machine to you or any other experienced nuggett hunter for experiment testing. Just want to tell you that I am not a dealer or interested in selling any detectors to prevent any misunderstandings, wanted to do this pet project for a few years. Better do it now and don't want to postpone any pet projects, life is short and I don't know if the COVID19 virus gets me this year or next year! No waiting for me anymore, it' now or never!
  2. HI guys! It feels very good that this nice forum is at high speed with all discussions about the AQ with all different subjects about the AQ.We are now in the middle of january and still nothing from the Fisher.No reports from any tester, no videos, no manual, nada...it feels kind of depressing without knowing any informations at all.I know that LE.JAG and Alexander can't say anything about these informations even though the know for sure.Is there any thought or any guesses about these questions?
  3. Came across this video of the AQ, filmed late December . Audio isn't great.
  4. Hello Guys, I'm new on this forum and like Alexandre Tartar, I live in north of France. I was a young prospector in the 90's and asked my father (electronic engineer with good knowledge in magnetic field theory) to build a PI to hunt the beaches. So we have made, in a few months, an home-made PI metal detector 25 years ago, based on the technology of the old White's Surfmaster PI (mono coil). I remember the use of FETs (Field Effects Transistors to make 200 volts pulses). It worked, but unfortunately, my father was afraid by a so powerful magnetic fields and has continued his research on VLF detectors, until today ! After this short presentation, here's my question : Is the Impulse AQ a bipolar detector ? Le Jag has explained us on the french forum "detecteur.net" this technology developped by Alexandre : Positive and Negative pulse are alternatively sent. The positive one light the gold ring but magnetize the soil. The negative one demagnetize the soil. What about it ?
  5. Demonstration of the high speed responses for various objects waved under the coil of the new Fisher Impulse AQ metal detector. HRS® "Highly Reactive System" Official Fisher video. Fisher Impulse AQ Detector Data & User Reviews Fisher Impulse AQ HRS® "Highly Reactive System"
  6. I think the Garrett ATX challenges the AQ most and maybe TDIBH come close after ATX only in raw depth.I have myself an ATX and hunt my beach with it. Max sensitivity givs me around 15 inches for a normal coin size object.My Garrett sea hunter is absolutly no match and even my Equinox has no chance.The fair comparisson is ATX (PI , almost same coil size,waterproof ) I think the AQ has only one tone for both high and low conductive targets and one for iron.The ATX has one tone for high and one tone for low conductive targets but you have no tone for iron which makes one to digg all.
  7. Many of you have expressed a desire to know how well the Impulse AQ will function for land use. One option is to wait until the unit is released. I know, no fun! The other option is to analyze the information we do have on the unit and on PIs in general, combined with information from the scientific literature and various forum posts. I have done such an analysis which is a bit long, but I will summarize the findings followed by how I arrived at the conclusions. The places where I believe the unit will be effective include the following: Black sand beaches (mainly coarse unweathered magnetite) Soils containing mildly weathered granite and other felsic igneous rocks (I know this appears to conflict with Alexandre’s post, but I will elaborate below) Unweathered or mildly weathered basic igneous rocks (basalt, gabbro, etc.) Places where I think the AQ will struggle include: Weathered basalt and soils derived from basalt Some fine-grained volcanic rocks such as rhyolite. The basis of my groupings above is the published magnetic susceptibilities (MS) for various minerals and rock types and on the concept of frequency dependent MS which is a very important consideration for PI detectors. MS is a measure of the magnetization of a material in response to an applied magnetic field. Frequency dependence is when the measured MS varies when different frequencies are used for the induced field. Minerals with high MS are responsible for the “mineralization” when speaking of metal detector performance. Three minerals are responsible for most “mineralization”; magnetite (Fe3O4), titanomagnetite, and maghemite (ꝩ-Fe2O3). The MS for these minerals are orders of magnitude higher than for other iron minerals such as hematite (α-Fe2O3), goethite, biotite, pyroxenes, etc. The relative proportions of these minerals within different rock types determines the MS of the rock. Ranges for different rock types are shown in the table below. Rock Type Magnetic Susceptibility Range (10-6 SI)1 Andesite 170,000 Basalt 250-180,000 Diabase 1,000-160,000 Diorite 630-130,000 Gabbro 1,000-90,000 Granite 0-50,000 Peridotite 96,000-200,000 Porphyry 250-210,000 Pyroxenite 130,000 Rhyolite 250-38,000 Igneous rocks 2,700-270,000 Average felsic igneous rocks 38-82,000 Average basic igneous rocks 550-120,000 Quartzite 4,400 Gneiss 0-25,000 Limestone 2-25,000 Sandstone 0-20,900 Shale 63-18,600 1. Compilation from Hunt et al. (1995) Minerals with high MS are responsible for the poor performance of VLF metal detectors. Hematite within soils is typically red, but given the relatively low MS, is not particularly problematic to metal detectors. So, red soil is not always bad! The MS of soil is a function of the parent rock from which it was formed (see table) and the degree of weathering of the iron minerals present. Soils formed from basic igneous or volcanic rocks such as basalt generally have higher MS than soils formed from felsic rocks (rhyolite, granite, etc.), but it depends on the specific rock. For example, some granites have low MS because they are dominated by ilmenite (S-type granite) as opposed to magnetite (I-type granite). Ilmenite has low MS. Geologists use MS to map different types of granite. Da Costa et al. (1999) found that the basic volcanic rocks from southern brazil produced soils containing maghemite (high MS) and hematite while the intermediate to felsic volcanic rocks produced soils containing goethite (low MS). However, there are examples of basic rocks having low MS and felsic rocks with high MS, it all depends on the mineralogy, the grain size, the degree of weathering, subsequent geochemical reactions during and after soil formation, and other factors. Typically, the smaller the grain size, the higher the MS. Therefore, a volcanic rhyolite which has a much smaller grain size than its intrusive equivalent granite, will have a higher MS even for an identical magnetite content. Smaller magnetite particles also weather faster than coarser grains. Magnetite can weather to maghemite on exposed outcrops. Maghemite is an earthy mineral that forms very small grains. The small grains produce a superparamagnetic domain which results in frequency-dependent MS which causes problems for even PI metal detectors, especially PIs which do not have the ability to ground balance (such as the Sand Shark and Impulse AQ). Magnetite can also form very small grains, and if small enough can also be superparamagnetic. However, magnetite tends to be coarse-grained while maghemite tends to be very fine-grained. Maghemite tends to form from magnetite and other minerals in tropical climates or where tropical climates once existed. The “bad ground” in Australia is due to the presence of maghemite, which is a brown to brick red mineral. Maghemite is less common in the US but is present. Magnetic anomalies found at the National Laboratory at Oak Ridge TN were found to be natural deposits of iron-bearing colluvium (sediment which has accumulated at the base of a mountain range) which has oxidized to maghemite (Rivers et al., 2004). Maghemite and hematite can be created from goethite (α-FeOOH) in response to the heat generated by forest fires and slash and burn agriculture (Koch et al., 2006). Therefore, poor detecting conditions can be created in such areas. The bad ground at Culpepper VA is probably due to maghemite, but I have seen no information to confirm this. Geologic maps of Culpepper Co. do show the presence of basic bedrock, such as basalt and dolerite. The granite that Alexandre mentioned as giving the Impulse AQ problems may be an I-type granite (magnetite rich) in which the magnetite has partially weathered to maghemite. The reasons for why I think the Impule AQ will or will not work in various soils/rock types is summarized below. Soil/Rock Type AQ Works? Reason Black sand layers on beach yes Black sand is derived from physical weathering of igneous and metamorphic rocks in upland areas and consists mainly of relatively unweathered magnetite. Soils derived from felsic igneous rocks probably Felsic igneous rocks with high MS, tend to be coarse grained and even when dominated by magnetite (I-type) do not typically produce maghemite unless highly weathered. Soils derived from basic igneous rocks Probably not Soils derived from basic igneous rocks tend to be dominated by maghemite. Basic igneous hot rocks maybe Basic igneous rocks such as gabbro can be a problem if weathered or partially weathered to maghemite. Felsic igneous hot rocks probably Unless highly weathered, felsic rocks are dominated by magnetite which the AQ should be able to handle Volcanic hot rocks or black sand beaches (i.e. Hawaii) maybe If fresh, the main source of MS is magnetite. If weathered or partially weathered to maghemite, the AQ may have problems. If very fine grained even unwethered volcanic rocks may present a problem. References Da Costa, A.C.S, Bigham, JM, Rhoton, FE, and SJ Traina. 1999. Quantification and Characterization of Maghemite in Soils Derived from Volcanic Rocks in Southern Brazil. Clays and Clay Minerals, v. 47, no. 4, p. 466-73. Hunt, CP, Moskowitz, BM, and SK Banerjee. 1995. Magnetic Properties of Rocks and Minerals. In Rock Physics & Phase Relations: A Handbook of Physical Constants, Volume 3. Koch, C.B, Borggaard, OK, and A. Gafur. 2005. Formation of iron oxides in soils developed under natural fires and slash-and-burn based agriculture in a monsoonal climate (Chittagong Hill Tracts, Bangladesh). Hyperfine Interact 166, 579–584. Rivers, JM, Nyquist, JE, Terry, D.O., and W. E. Doll. 2004. Investigation into the Origin of Magnetic Soils on the Oak Ridge Reservation, Tennessee. Soil Science Society of America Journal, Vol. 68 No. 5 p. 1772-1779.
  8. I may have missed this issue..you know I am not very smart. will the prospecting, nugget finding version be wireless? I could not, would not buy another detector that doesn’t have a module. thanks fred
  9. It arrived yeaterday late afternoon. Just unboxed it - will edit the VERY short video I made and get it up today. Meanwhile here’s a teaser - if you saw pictures of the prototype, you might notice that there is an new mode “volcanic sand” and that the SAT knob is now marked ATS (it’s a Fisher thing) and the Iron Mask knob is now marked Reject
  10. I think it will also be interesting to see what an aftermarket company might do with the 7uS coils. Will we see more if this machine catches on? Better yet will we see 7uS become the standard? OR... is that a non-issue toward depth and sensitivity?
  11. The new Fisher Impulse AQ is doing something new with pulse induction discrimination. I think I have a pretty good idea of what the engineers are up to and so want to pass on my thoughts in case it will help people have a better idea of what to expect. I have posted numerous articles in the past about coin detecting with ground balancing PI detectors. GBPI detectors split targets into two classes depending on the ground balance setting. The two target classes exhibit by different tones. All Minelab PI detectors do this, as do the Garrett Infinium and ATX, plus the White's TDI series based on the Eric Foster Goldscan. White's on the TDI labeled these as low conductors and high conductors but that is not actually accurate. They are items with a low time constant and items with a high time constant as measured on a pulse induction metal detector. For more on signal decay and time constants see the excellent primer by Reg Sniff Understanding the PI Metal Detector. If you could measure the time constant of the various targets and line them up you would see size has a lot to do with it, small items versus large items regardless of composition. White's TDI "Target Conductivity" switch (notice ground balance on required) I caught on to this fast with the Garrett Infinium in 2004 and Minelab GP 3500 in 2005 and when the time came it was I who suggested the tone switch be incorporated into the White's TDI to allow the user to choose between one of the two classes of targets. Plus the TDI allowed the operator to directly set the ground balance, creating a crude discrimination system for savvy operators. It is actually possible to coin detect with a TDI and dig almost no trash, but you lose its PI depth advantage by setting the machine that way. I preferred using the tones with full depth settings myself with excellent results. The two target classes vary depending on the exact ground balance setting, but generally one one hand you have low conductors and small ferrous targets, and on the other hand coins and large ferrous targets. This means if looking for small gold you dug all manner of small trash including small ferrous trash. Coins were better but you would still dig large nails and other large ferrous items. The TDI allowed a person to advance the ground balance to where most ferrous trash could be eliminated while still getting the coins, but the setting was so close to the coin range to do this that depth suffered as a result, and so was no better than a decent VLF. It's a long read but a lot can be learned by reading the following three links. Coin Detecting with the Garrett Infinium Beach Detecting with the Minelab GP 3500 Coin Detecting with the White's TDI Some Commentary On White's TDI Tuning & Discrimination It can be seen that as far back as 2005 I was predicting that high power PI detectors would find widespread use with beach hunters and relic hunters in particular. That prediction did later come true at Culpepper and other locations. It was obvious to me that this crude discrimination offered more room for improvement. I even emailed Carl Moreland at one time and made mention of the concept of using two ground balance controls to delimit another class of targets beyond the two created with a single ground balance point. But really it is not ground balance, it is just a setting that measures a certain time constant. And that folks, is basically what the Fisher Impulse is doing. It is using at least two dividing points to separate items into three classes, lowest time constant, middle (gold ring) range, and highest time constant The Impulse is eliminating the items with the shortest time constant and the longest time constant and focusing on the mid-range. This eliminates tiny trash and tiny gold, and large ferrous stuff and most coins. What is left is the sweet spot in the middle where gold rings occur plus a yet to be determined range of trash targets. There will be some, that is inevitable, but the vast majority of trash should be eliminated with this approach. This picture shows the result of using the Garret Infinium and separating the short time constant targets from high time constant targets in tot lots. Low constants (nickels and zinc penny plus trash) on left and high constants (copper pennies, dimes, quarters) on right. Notice very little trash with the coins if you dug that class only. But that is deceptive due to the location, which lacked any nails. Garrett Infinium targets separated by tone So take a look at this result from a park, this time only the long/high time constant targets with the TDI... coins and large nails. White's TDI low tone / high time constant targets OK, so let's combine the two to get a clearer picture.... Left of red line low time constant versus right side high time constant targets To reiterate, having only one point of separation presents issues. You get coins but you also get large nails. And the low time constant area is a mess, just way too much stuff including small ferrous. But in areas with few nails it actually works well for coins. The dividing line does vary with the ground balance setting but is roughly about zinc penny if ground balanced in moderate to high mineral ground. The Impulse AQ is basically blowing off the high end to get rid of the nails, and the high conductor coins also get tossed out. Most jewelry hunters will be fine with that - digging coins in the surf is a waste of my time and effort. The AQ is adding another separating point somewhere in that left hand low time constant area, that eliminates the tiny stuff including I assume most wire type ferrous items and foil. Rings due to the round shape with a hole read better than most of the misc trash in the photo. However, some of those items will read in the ring range so do not expect the AQ to be trash free. Trash that reads close to the nickel range will probably come through, like pencil eraser ends and some tabs that read like nickels. If you think of the AQ as a nickel detector that will probably not be far off the mark. My biggest area of concern is zinc pennies, especially corroded ones. I hate those things but I suspect we will be digging them with the AQ. All the above is just speculation based on everything I have learned using this class of detectors over the last 15 years. I have had no part in the AQ development. That said, I think most of what I am describing will prove to be pretty close to the mark as far as how the discrimination functions on the Impulse AQ. And just a reminder. The Impulse AQ will let you turn off the discrimination to run in pure pulse mode, presumably with no ground balance engaged. It should be at similar to but more powerful than the TDI Pro with ground balance shut off. This will not be good for nugget detecting in most areas as it will light up hot rocks, but for many beach detecting situations should be giving us a detector like the famed Eric Foster Deepstar in a much more ergonomic and affordable package.
  12. I know this is asking a bit too much but for some hunters, a “Lite” version of the AQ would be perfect, especially if it was cheaper 👍 I would be happy with a version minus the REJECT knob and associated 3 ID modes. Running in AM and being able to tweak the pulse delay and ATS is all I need. Having said that, I fully appreciate and respect what has gone into the AQ Impulse....it is “a lot of gun” 🤠 Tony
  13. Explanation of new coil mounting system on the new Fisher Impulse AQ metal detector. ZPT® "Zero Pressure Technology" Official Fisher video. Fisher Impulse AQ Detector Data & User Reviews Fisher Impulse AQ ZPT® "Zero Pressure Technology" Fisher Impulse AQ ZPT® "Zero Pressure Technology" detail image
  14. Demonstration of how the new Fisher Impulse AQ handles non-ferrous items surrounded by or under ferrous trash. ZTS® "Zero Target Separation" Official Fisher video. Fisher Impulse AQ Detector Data & User Reviews Fisher Impulse AQ ZTS® "Zero Target Separation"
  15. And a survey of what a reasonable price "is" would be interesting. TDI or SDC price tiers, or maybe a little more. There is a very long development cycle to be taken into consideration, as well as production costs. Will the coils be machine wound or have to be laid up by hand? Two forward looking warranty concerns, 7us tolerances(drift) & waterproof. There are a lot of knobs on this unit and everyone of them is a potential moisture entry point. You have to cost these factors for worst case projections so in essence you are paying for insurance up front should disaster strike.
  16. In the absence of a manual, a summary breakdown of what the controls do combined with an explanation of the various tone modes (in the same post to avoid having flip around the threads, having trouble interpreting Le Jag’s post) would be helpful when you have a chance, Rick. Thanks.
  17. Anyone who has used a White’s TDI much knows that the ground balance can be manipulated to exclude certain targets. This is less about conductivity as White’s sells it, but about target size. What that means is you can exclude high conductors and large ferrous and concentrate on smaller low conductors and small ferrous. Or you can exclude small ferrous and small non-ferrous and go for higher conductors and larger ferrous. The system does not make gold hunters happy because to dig small gold you still dig small ferrous stuff. Or when you are digging larger gold you still dig nails. My guess on the Impulse is that it is using at least two “ground balance” points to bracket the most common ring responses, which tend to be lower mid-range targets. It would be quite a balancing act tuning out both the smallest stuff and the largest stuff and just hit the sweet spot. I personally think this could be a powerful method for essentially cherry picking rings while eliminating most small ferrous and large ferrous. There still will be a class of mid-range ferrous targets that read good - I promise the system can’t be perfect. The flip side however is that at least two large “holes” are going to have to exist as a result. One that misses smaller gold targets, like earrings and chains, and possibly the smaller thin rings. And then on the top end very large heavy men’s rings and silver rings, and most coins may also be lost. The solution will be to turn off the discrimination and go back to digging everything. Hopefully there will be some ability to tweak the discrimination as target / trash mixes do vary somewhat and shifting the accepted range up or down would be beneficial. I am just guessing based on what I know about how a PI works and how one could potentially discriminate out a class of targets. I could see a very acceptable trade being made, more depth at the expense of certain target classes. Yet I wonder how the general public will react to videos displaying numerous gold items, especially large ones, being completely undetectable by the Impulse in discrimination mode? The wiser among us may understand what’s going on and the trades being made, but if I know one thing about a lot of folks, the idea the machine misses good stuff won’t fly too well. Witness the silver dollar on edge fiasco with the Equinox, or the similar issue with the early Gold Bug models. Anyway, don’t take this as being more than speculation, but it is something that the more knowledgeable among us will want to find out quickly once the Impulse hits the streets. It should be easy to find out, just air test with a large range of jewelry targets running from tiny to large and check the results. And the same with ferrous. Unless a Pulse Devil miracle machine is in the works, and I am betting that’s not the case, there will be some definite caveats to deal with when employing the discrimination system. For me it’s kind of a non-issue. I’d be happy with the machine as a straight up pulse digging everything. It’s the ergonomics and price along with the finely tuned low pulse delay that have me looking more than some magic discrimination system. Anything it does there will be just a bonus. I will actually be surprised if the nugget hunting terra version has any discrimination at all due to the possible issues I am outlining. It would tune out most natural gold nuggets. Optional blocking of high end nail type signals would be of more benefit to nugget hunters in small gold areas. It would risk missing large nuggets but in some places that’s not much of a worry. Fisher Impulse AQ Data & Specifications Fisher Impulse AQ pulse induction metal detector
  18. The Impulse AQ has a volume control. The headphones are not the ones Fisher has used for a long time on the 1280X and CZ-21. They look more like the DetectorPro Amphibian without external volume control than anything else I have seen. Should be a great fit, and hopefully we for once will get an underwater detector that has excess volume enough for underwater use. The headphones have a unique but easily obtainable three pin connector so aftermarket phones should be quick to follow. As will some kind of dongle to convert to 1/4” so we can use dry land headphones or wireless adapters. Fisher would be smart to make the dongle available themselves but we will see. Photos by Rick Kempf, click for larger views.
  19. Just read on another forum that LE JAG will soon be testing an 8" coil on the Fisher Impulse AQ! Should make some folks have a Happy New Year. Bill
  20. Per a conversation I had today with Tim Mallory - VP of marketing and sales at Fisher/First Texas - I am apparently “customer zero” for the AQ. For reasons of copyright protection (which I don’t understand) it was important to sell exactly 1 Fisher Impulse AQ in calendar year 2019. I guess because I am a PITA, I was invited to be it. It had to be a bona fide sale, so I am paying for it - cheerfully. Can’t discuss the price because that may or may not equal the eventual launch price. I am told it will ship Monday. Since I figured that I was “in the catbird seat” I asked them to include a Fisher cap to replace the one I lost a while back. My nearest US beach is in San Diego and I have no time to drive there soon. I will be doing an “unboxing” video and some stuff of using it inland here in Gold Canyon AZ - where there is no gold. Imay borrow some of my wife’s “minor” bits to practice with however.
  21. Me too. 😕 I'm hoping when it does come out that it does not pick up these rocks. They read #1 on the Equinox - right where the small gold and chains read. I would be willing to pay postage and send some of them to Fisher to make sure they are invisible to the Impulse AQ
  22. Just noticed the pulse delay ranges from 7 to 12 in comparison of the TDI 10 to 25. Now this is for the salt water environment and not for dry land "Terra". I might surmise the 12 would be more than adequate for the salt water hunt but on my TDI a pulse delay of 17 1/2 is required. Always good the ponder why!
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