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PimentoUK

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  1. Fellers? I'm just one, not a consortium. Best depth is achieved with disc set to Zero or 1. Set Disc to about 11 if you want to lose lots of depth... maybe if you have bad EMI, it could help deal with it, as an addition to lowering the sensitivity.
  2. To get to the 'disc mode', you need to press the mode button until the highlighted option is the top-most one. Then turn the rotary control counter-clockwise one click, and the disc mode is highlighted. Then the mode button will cycle through the left menu. The 'notch' feature is a mess. Poorly designed, poorly documented in the user manual. And you can't assume " Well I never use it, so it's not an issue" , because it's very easy to inadvertently put in some notch. Then the problems start. Thankfully, a simple solution exists: Factory Reset. Learn and relearn how to do this, and 'notch nightmare' is not a problem.
  3. Ferrites are shinier and silver-grey colour. They are normally extremely hard, you can't abrade them; scratch them with a knife, you get a silver steel streak on the ferrite. Powdered iron is duller and blacker, and is medium-hard. With effort, you can scrape off small bits, and strong abrasives like silicon-carbide paper will remove it. So the ML ring is powdered-iron. The colour isn't very informative ... they might just have painted it black themselves to hide the manufacturers part marking. The 'Doc' toroid seems typical of ferrite: shiny, hard. But ferrite is almost always electrically non-conductive, though I have read about some that will conduct ... I have no idea what type. 38 Ohms is surprisingly low. Again, color coding is hard to interpret .. yellow with one white face is typical of Type 26 ferrite blend. Edit: It is the very-high mu ferrites that are electrically-conductive ( mu over 5000 typically ), and I've just measured one example ( probably mu=15000) in my 'bits box', and it reads 200 Ohms across its diameter. That may be indicative of the 'Doc' ring material. Jason: Do you have an inductance meter? Wind 50 turns of enamelled copper wire on each toroid ( diameter 0.15 to 0.6mm, not important ), and see what an L meter gives. I guess the ML one will measure about 30 microhenry. The 'Doc' sample may be anything, up to 20 millihenry.
  4. A few observations from an electronics guy, who has used these toroids. There are two distinct 'types' of material used in these toroids: Powdered Iron, and Ferrite. 'Powdered iron' is ultra-fine iron dust, that is produced by chemical reaction, (rather than mechanical grinding etc ). There are some similar nickel-iron alloys ( eg. Permalloy) and other exotics like Sendust that can also be considered 'Powdered iron'. 'Ferrite' is non-metallic ( officially a ceramic ) that's essentially rust ( iron oxide ) with small quantities of metals like zinc, manganese blended into it. This is turned into fine powder by mechanical grinding, and then moulded. They have quite different magnetic properties. Powdered irons have low magnetic permeability, (mu), typically varying from 1 to 100. Ferrites generally have higher mu, from 50 up to 15000. Minelab specify a low-mu powdered-iron toroid, not ferrite, for detector balancing: Quote: "A ‘dust iron’ toroid suitable for the HF frequency band (e.g.1–30MHz with an initial permeability of between 6 and 10) has been carefully selected." Regarding colour-coding: It's primarily a powdered-iron thing, even then, different manufacturers have different coding, and there's plenty of different materials/blends that it's not worth trying to identify a toroid by colour. Magnetic testing will tell you much more. Ferrites have no useful colour-codes, and are often unpainted, as they are naturally corrosion-resistant. So if you're wanting to self-select a toroid for detector set-up, you want permeability, mu, of 6 -> 10, and a physical size that's vaguely the same as the ML suggested type, though it's not critical. For reference, here's Amidon Corporations data sheet for ferrite and iron cores ( pdf ) http://www.amidoncorp.com/product_images/Amidon-Tech-Data-Flyer-v19.pdf
  5. I see the word 'Quartz' among the 'metal type' list ... a bit of a red flag to me. It makes me wonder if it's related to some kind of 'esoteric' detector , the kind that have five radio antennas on them, and a bottle of Gypsy Tears inside the handle.
  6. Any thoughts? Yes, actually. See the missing suite of components ... four 'large' electrolytic caps, a three-pin device ( switching FET, usually ) and a large damping resistor, and the silk-screen legend 'Coil2'. Enough bits to drive a second coil winding. Those who have followed Alex's design from the early days will know how he had plans for some 'twin-coil' arrangement, that apparently could largely cancel the ground/salt signal. He posted up some 'sketches' over on Geotech1 forum, but no-one could make out what he was describing. https://www.geotech1.com/forums/showthread.php?23177-Manta-Metal-Detector The other obvious stand-out is the thermal management. I think if they had made the case a bit larger, they would've given themselves an easier time when it comes to heat-dissipation issues.
  7. That's a more realistic way of doing it, and the existing Deus coil electronics will work fine. The topic of a two-box that runs multi-frequency came up some years ago on the Geotech1 forum. But no-one could work out if it would have any real benefits over a single-freq. Having selectable single frequencies would be good, and multi-freq machines like the Equinox and Deus2 both do this. The Deus2 would have the advantage of being capable of operating at any frequency the designers wanted, including very low ( 1 kHz- 5 kHz range). Maybe if this XP two-box ever makes it to customers, it would be Deus2 compatible. The primary advantage of multi-freq is its ability to eliminate the ground signal. As two-box machines are used with the coil well clear of the ground, they will obviously pick up less ground signal, so maybe the benefits of multi-freq are largely lost.
  8. It might be an idea to put a question mark '?' in your title, I suspect I'm not going to be the last to look at this thread to see what new features ML are giving us with this surprising update ....
  9. That will be SAW for sawtooth, I imagine.
  10. Advice? Large piles of silver coins are very scarce. I recommend just living with this 'feature' , and get out there finding plenty of stuff that the Simplex will detect. Detectors aren't perfect, they'll happily tell you iron is non-iron, they'll call non-iron items iron if they're deep/weak/close to iron/on-edge etc etc. Just as a matter of curiosity, are your 'Investment grade' coins .999 fine, or are they 0.90 coin alloy? The difference in electrical conductivity is noticeable, and a pile of quarters/half-dollar coins will not read like a few one-ounce US Mint proofs.
  11. For information about the Pulse Star 2 detector, I recommend joining the Geotech1 forum. You will find several discussions about this machine. For example this one: https://www.geotech1.com/forums/showthread.php?25437-Pulse-Star-II-(first-analog-version)
  12. Quote:"Their machines are made for big brute Aussies" The Equinox isn't that heavy. The lower rod is proper wound carbon fibre ( rather than moulded plastic loaded with carbon fibres ) , so it's pretty light and stiff. And if you examine the aluminium rods, you will find they are not a standard wall thickness, the are noticeably thinner. Imperial 7/8" size tubes typically have wall thickness of 48 thou, 50 thou, 58 thou ( 1.22mm , 1.27mm , 1.47mm ) , and these are what you find on many detectors, ( and hospital crutches, radio antennas etc ). The Equinox uses 40 thou / 1mm wall thickness tubes, and so are lighter as a result. It feels a bit heavy because the stock 11" coil is large as 'standard' coils go, and a heavy coil will always be felt, being situated on the end of a long shaft. You are right in saying a 9" coil as a 'stock' option may have been a good marketing strategy.
  13. Easy to hoax, just fix the Deus coil under the table.
  14. My PC is not a super up-to-date one, that kind of stuff probably won't work. Pretty soon, it will fail to handle YouTube completely, I regularly get warnings about it.
  15. Quote Chase: "I don’t know what you are referring to when you say a target’s “frequency”" I suspect you may have missed my earlier thread about calibrating the Equinox VDI scale: ( I will edit my earlier post in this thread to link to it ) A target's "frequency" is that detector frequency which causes it to have a 45 degrees phase lag ( or 90+45 degrees, depending on your 'reference' phase). Or ... you can alternatively measure what phase lag it has at some other frequency, and mathematically calculate what the '45 degree lag' frequency would be. A target can essentially be modelled as an inductor with a resistor connected to its ends. So it has a 'first-order' response, much the same as a first-order low-pass filter you may be familiar with from electronic engineering studies. These can be R-C, or L-R filters. The relevant behaviour is that feeding it with a very low frequency produces very little phase lag; drive it with a very high frequency, you will approach 90 degrees lag. The 45 degree lag point is when the driven frequency matches the 'filter' frequency: f = 1/(2*pi*R*C) = R / ( 2*pi*L) It's actually possible to use a real inductor-resistor combination as a target, they work well. Alternatively, a closed wire loop is viable: though the L and R values are tiny and practically unmeasureable, they can ( with difficulty ) be calculated, hence the target frequency can be determined.
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