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  • Tinkerer

    Moodz is pretty close to right. Actually the top producers are China,
    Australia,USA,Russia,and Africa ,in the order I have wrote them.

    South Africa has actually dropped in production for the last few years.
    The so called third world countries are at the bottom for production.
    Most gold production is from several large mines,and in some cases,a
    by product of copper mining.

    Also in your last post,you pretty well answered your own question. It
    is not worth the effort or expense to deal with third world countries ,
    where the government,makes it impossible for their own people to buy
    at a decent price. No one wants to do business ,where the government
    changes hands ,at the drop of a hat either.

    Comment


    • I might disagree with Tinkerer about where most of the world's gold comes from, but he is correct that Third World countries offer a tremendous market for gold detectors. Even accounting for duties, smuggling, and bribing. It's huge. Gargantuan. Bigger than all the US, Australia, and Europe combined.

      Comment


      • Tinkerer

        I know a little more about subsistence miners in third world
        countries than you may think.

        If you can produce a suitable detector for $300.00 or less,what
        will be the initial market price,at the wholesale level?

        To use your example of inflated customer prices,there is something
        wrong with this whole picture. The miner is getting a questionable
        entry level detector for an inflated price,due to duties,and other crap.
        His cost is $1000.00 or more. There is no way that those miners receive
        even close to spot price for their gold. After dealing with crooked gold
        buyers ,most are lucky to get just a portion of spot price. It would be
        a safe bet that,the miner would have at least an ounce of gold or more
        invested in an El Cheapo detector.

        There is no way that I,You,Carl or anyone else that knows better,would
        buy such a machine ,and depend on it for our living. If all you are interested
        in is selling detectors,yeah it would probably make some money. But if you
        are trying to help those miners,it is a joke.

        In the first place,you don't need a detector to find an outcrop or vein.
        There is nothing wrong with digging either. I have found a heck of a lot
        more gold,by digging than most have with the best detector made.

        If you are really concerned with these miners plight,a detector is the
        last thing they need. They can find the gold,but their primitive process
        methods is their worst problem. Then being cheated every time they
        turn around doesn't help either.

        Comment


        • Originally posted by kt315 View Post
          Tinkerer,

          what you CONCRETELY offer? there was a man wishing to buy Hammerhead from me. I asked $80 for soldered PCB with a coil. I do not see him FROM THE TIME
          Should have charged him $800, he would have pulled your arms off for a "Custom machine".

          Metal detectorists are suckers (in the main) who have become conditioned into believing that in order to get anything worthwhile, you have to spend $$$! I think Silverdog has proved this to be VERY wrong!

          Let’s take the E-Trac, how many are for sale on eBay as the owners are selling them to finance the purchase of Scambins latest offering? At $2500 they need to take out a loan or max out a card or two also. Do Scambin care? NO they don’t give a f*ck if you can’t afford this months mortgage payment, yet suckers are champing at the bit to hand hard earned and ill affordable cash over.

          Now please don’t think this is an “anti” rant because I have no doubt that the new machine is a great piece of kit, but it is NOT worth $2500!!

          Manufacturers need to get real in the price department, and so do the end users. The ONLY reason you see these high prices is because the manufacturers know people will pay it. If everyone says "NO" then you would soon see the prices tumble.

          MORE is not always more!

          Comment


          • Originally posted by Sean_Goddard View Post
            Should have charged him $800, he would have pulled your arms off for a "Custom machine".

            Metal detectorists are suckers (in the main) who have become conditioned into believing that in order to get anything worthwhile, you have to spend $$$! I think Silverdog has proved this to be VERY wrong!

            Let’s take the E-Trac, how many are for sale on eBay as the owners are selling them to finance the purchase of Scambins latest offering? At $2500 they need to take out a loan or max out a card or two also. Do Scambin care? NO they don’t give a f*ck if you can’t afford this months mortgage payment, yet suckers are champing at the bit to hand hard earned and ill affordable cash over.

            Now please don’t think this is an “anti” rant because I have no doubt that the new machine is a great piece of kit, but it is NOT worth $2500!!

            Manufacturers need to get real in the price department, and so do the end users. The ONLY reason you see these high prices is because the manufacturers know people will pay it. If everyone says "NO" then you would soon see the prices tumble.

            MORE is not always more!

            Totally agree!

            Comment


            • Originally posted by MXT SNIPER View Post
              As a part time coin/gold jewelry detectorist and part time gold miner, nugget hunter, I would like to see a true multi purpose detector that will work for us well in both modes, nothing now exists that will. It would have to be built around a detector like the gold bug 2, which can be used to chase tiny veins and tiny nuggets, No other detector out there comes close to this one in this category, we have tried em all, including the gold bug pro, mxt, etc. I have friends with a very successful hardrock pocket mining operation, and nothing beats the gold bug 2 for their use for tracking tiny stringers of gold while hunting for large pockets, I was thinking if a detector could be built to incorporate both the sensitivity of the gold bug 2 in a high 71khz op freq or higher, combined with a 13-14.7 freq for gold jewelry/coin hunting with switchable freqs for this, it would be great. I would be very happy with these two approx freqs in one detector, especially in a lightweight version like the f75 with disc in all metal also. We have found that the mxt is hot on gold jewelry as well as the tesoro compadre and vaquero. All the current multi function detectors on the market now fall far short when hunting micro nuggets and tiny veins. Some are very good detectors like the mxt, Vaquero, F75ltd, Eureka Gold etc. but they fall far short in some mining applications. Just some rambling thoughts on the subject.
              Thanks for the feedback, MXT SNIPER and WOODY.AU.

              Would you like to expand a bit more on your ideas?

              I think we need to get away a bit from the marketing angle and take a closer look at some new ideas. Open the horizon a bit.

              So, please all new and good ideas on the table.

              Technical ideas, ergonomic ideas, all kind of ideas to improve the metal detector world.

              Tinkerer

              Comment


              • THE PIVOT SOFTWARE CHALLENGE.

                THE PIVOT, software challenge.

                I am asking for new ideas, do I have any of my own? Yes, I have some, here are 2 of them:
                A few days ago, when I was making the thickness tests, I saw again THE PIVOT on the CRT screen. Eric Foster mentioned THE PIVOT and I posted some pictures time ago, but few people believed that THE PIVOT might be the key to PI discrimination.
                FE discrimination and also TC based discrimination.
                So I will try to take some pictures again to explain how it works.
                How can we process the signal to take advantage of THE PIVOT?
                I think an algorithm could be designed that can extract the useful information that I can see on the scope. So this is the software challenge. Can somebody write the code to decipher THE PIVOT and convert the information into a user friendly output?

                On to the next idea:

                A few days ago, Carl said:”
                Another detector challenge would be a high-security walk-through design. In prisons, they want to be able to detect a hypodermic needle hidden on a person's body walking through a 24" wide gate, at any angle. Or a small razor blade.

                I had a coil and drive that could detect a very small needle, but not in any position, only flat. So I started thinking. How could I detect this needle IN ANY POSITION.
                How about building a magnetic field that does have specifically designed directional vectors.

                Can we make the magnetic field of the coil go in the direction we want?

                I found that yes we can.

                And it would be quite useful. For example we all know that a coin is easily detected in the flat, or horizontal position, but produces a much weaker response in the vertical position. If we could focus the coil field so that it hits the vertical coil from the side, the response would be much stronger.
                Can we bend or focus the coil’s magnetic field around a curve? Yes we can and it might open a whole new horizon in detecting.
                Unfortunately, my explanations are usually hard to understand as some of it gets lost in translation, so I will draw some pictures of the coils magnetic field and how we can drive it around the bend.

                In the meantime let’s see some other new ideas. Who dares???

                Tinkerer

                Comment


                • Pivoting is clearly observed in log scale. Instead of using a log amplifier to observe it directly, you can as well take several samples, and give them log gains. You can assign these gain numbers some higher meaning and patent them with some techno gibberish explanation

                  In log scale all real exponential functions appear linear, however, when a log signal hits the log span limit (every log amp has upper and lower limit) or the observed function has some other component, say linear, the observed signal appears ski-like.

                  Comment


                  • Formula finder(c)(r)(tm)

                    Hey guys,

                    if you provide enough data, I can perhaps use my formula finder(c)(r)(tm) and you will have the best possible formula to solve a particular task (for instance the GB or disc). It is based on Monte Carlo method using the defined set of functions/operations (every math function) and the software tries every possible function/operation to match the problem with least error.
                    This reduces the required horse power to the MCU/DSP heavily.

                    Don't ask for the formula finder(c)(r)(tm). I'm not going to give or sell it. And this is the first time, I am mentioning the formula finder(c)(r)(tm). It is well beyond the scope of the market leaders engineers of course.

                    Aziz

                    Comment


                    • Originally posted by Davor View Post
                      Pivoting is clearly observed in log scale. Instead of using a log amplifier to observe it directly, you can as well take several samples, and give them log gains. You can assign these gain numbers some higher meaning and patent them with some techno gibberish explanation

                      In log scale all real exponential functions appear linear, however, when a log signal hits the log span limit (every log amp has upper and lower limit) or the observed function has some other component, say linear, the observed signal appears ski-like.
                      Thanks for the feedback.
                      http://www.geotech1.com/forums/showp...03&postcount=5

                      At the link above, there are scope pictures about THE PIVOT. THE PIVOT is the place in time, where the target signal wave shape changes polarity.
                      If the target signal is negative compared with the "no target" signal, then it passes a 0 spot and then goes positive. Or inverse.

                      The problem is that the 0 spot is not absolute in it's voltage level, it moves up or down depending on target size.

                      This explanation is hard to understand, so I give an example. If I take 5each 1us samples centered around THE PIVOT, I may get -20mV, -10mV, 0V, +5mV, +10mV.

                      THE PIVOT at "0V" will then move earlier or later in time indicating the TC of the target.

                      The pictures above are old, now I have perfected the TEM method thanks to Aziz's help and the definition is much better. I have also figured out the relationship of the THE PIVOT with the TX wave form.

                      When I made the "Thickness Test" I noticed some interesting things. For example, the copper targets have a long TC and it shows very distinctly with a late PIVOT. The 1" aluminum foil targets have a very early time. etc.

                      An interesting one is a very thin rusty steel disk. It shows a late PIVOT when presented flat, but it shows the same PIVOT time when presented vertical.

                      In other words, I believe that THE PIVOT can be used like the phase angle with VLF, to identify the targets.

                      Tinkerer

                      Comment


                      • Originally posted by Aziz View Post
                        Hey guys,

                        if you provide enough data, I can perhaps use my formula finder(c)(r)(tm) and you will have the best possible formula to solve a particular task (for instance the GB or disc). It is based on Monte Carlo method using the defined set of functions/operations (every math function) and the software tries every possible function/operation to match the problem with least error.
                        This reduces the required horse power to the MCU/DSP heavily.

                        Don't ask for the formula finder(c)(r)(tm). I'm not going to give or sell it. And this is the first time, I am mentioning the formula finder(c)(r)(tm). It is well beyond the scope of the market leaders engineers of course.

                        Aziz
                        Thanks for the offer Aziz. I am sure that you will quickly find an algorithm for THE PIVOT.

                        It would be great if you could use your coil field software to show how we can focus and drive the coil field around the bend.

                        I believe the focusing will greatly reduce the EMI, while concentrating the magnetic field where we want it.

                        I have not made the coil drawings yet, I am not good at drawings, so it takes time, but I know you will understand if I just give the basic idea.

                        Take a single loop. The magnetic field will form an approximate sphere around it, with all the field lines passing through the center. On the outside, the field lines are spread out very much, so that a target that would intercept many field lines at the center of the coil, on the outside it will intercept only very few.

                        Now look at a solenoid. It is surrounded by an oblong field. We have stretched the field a little. Everything else is about equal.

                        Now take a long solenoid and bend it all the way around where the beginning meets the end. Now we have a toroid. Things are different now. There is nearly no field outside. The field is mostly inside the toroid. Some people call a toroid self shielded, because it is nearly impervious to EMI and also emits very little EMI.

                        Now we open the toroid and make a pacman. With some space between the beginning and the end of the toroid, the field still stays inside the toroid.

                        Now open the toroid more and make a slinky, or horseshoe. The field stays inside the winding and jumps across the opening in an arc, spreading only a little. We still have a very concentrated field.

                        The arc that the field makes should be proportional to the diameter of the coil. This is what I would like to confirm.

                        If it works the way I hope, there are several other coil arrangements that should be possible and of benefit.

                        Tinkerer

                        Comment


                        • Half Toroid

                          Hi Tinkerer,

                          see below (if I have understood it correctly). Not much promissing IMHO.
                          Cheers,
                          Aziz
                          Attached Files

                          Comment


                          • Thanks Aziz,

                            I am quite happy with what I see on your visualization and it is a good step towards what I am looking for. The vector arrows are excellent. This shows us the angle of incidence on a flat target like a coin that will give the strongest response.

                            The idea is not a deep penetrating field, rather it is to see if we can make a focused field while at the same time make it little susceptible to EMI.

                            With the half toroid, we see some asymmetry in the field.

                            With the full toroid, the whole field stays inside the toroid. When we make a small opening, the field still stays inside. Opening more, there is some point, where more and more of the field comes outside.

                            We do have some way to control the field.

                            Now, when we look at a horseshoe magnet, we see that they usually have a half circle that is extended with 2 longer legs. These longer legs have the purpose of directing the magnetic field to the extremes of the legs. The field then stays mostly inside the horseshoe, but is very strong between the ends of the 2 legs.

                            I hope that the toroid in the horseshoe shape will give some similar results.
                            Then there should also be a difference if the angles of termination on the legs of the horseshoe are different.

                            Another way of directing the field vectors, would be a solenoid in an hourglass shape. The hourglass shape is also used as a ventury in hydraulics. The resulting field should then be more pumpkin shaped, as opposed to the oval shaped field of a normal solenoid.

                            Now what happens if we apply the hourglass shape to a toroid? Or to a horseshoe? How will it influence the field shape between the ends of the legs?

                            We appreciate very much your help Aziz. Thanks a lot.

                            Tinkerer

                            Comment


                            • Bu the way , it seems to me a good idea to make 2 perpendicular round coils of equal diameter , and send the pulses to them alternately . One coil will give vertical magnetic flux and another one horizontal flux ( in the ground ) , so we can catch 2 different responses from one object . And if the first response is much weaker than the second , we'll consider the object as vertical standing coin , for example .

                              Comment


                              • Originally posted by deemon View Post
                                Bu the way , it seems to me a good idea to make 2 perpendicular round coils of equal diameter , and send the pulses to them alternately . One coil will give vertical magnetic flux and another one horizontal flux ( in the ground ) , so we can catch 2 different responses from one object . And if the first response is much weaker than the second , we'll consider the object as vertical standing coin , for example .
                                With the coils equal, the vertical coil target response will be very much less, because only few magnetic field lines will be intercepted by the target.

                                2 coils side by side, with magnetic fields aiding will produce a fairly large region where the field is strong and the field vectors are angled.

                                This might be worth looking at.

                                Tinkerer

                                Comment

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