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jasong

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    Wyoming
  • Interests:
    supernova flotsam
  • Gear In Use:
    7000 w/ X Coils, 6000, EQ800, Deus 1. Heavy equipment, XRF, fire assay furnace, range of sensors. Commercial mineral exploration.

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  1. This looks like a basalt porphyry (or porphyritic basalt if you prefer) to me. It's not uncommon in Arizona and often forms these rounded stones I just call basalt bombs, they suck to detect around.
  2. Yes, I exclusively used zippered boots from the day I started detecting as I don't like wasting time on laces. Most plastic zippers still had a metal eyelet on the bottom, or sometimes a part of the zipper would be metal too. The eyelet usually wasn't a problem (if it signaled it was weak and always the same place) until I moved into bigger coils on the GPZ. Pretty much every pair would end up bending/warping a bit on the zipper or losing a few teeth at season's end, but most lasted as long as the boot did before wearing holes into the toe, heels, or the stitching blowing out, so the zipper failures generally happened after the boots were bound for the trash anyways. I couldn't get a pair of Bates to last a whole season. Solid leather 5-11 (discontinued) and the old standby Converse/Reebok zippered boots were slightly better but I'd still destroy them after 1 season to the point I needed a new pair. Moved to the slip on composite toe Wolverines - less failure point than with zippers, waterproof, and these seams haven't failed on me yet, and I don't wear holes through them in 1 season from kicking ground - plus absolutely zero metal. Most durable soles of any boot I tried by far. After 2 years of use now I can say yhey are my detecting boots and every day footwear too now. Finally gave up the zippered boots, To me they are the best detecting boots out there, but ankle support lacks compared to laceups.
  3. @Geotech It's interesting to observe that the EMI problem in your video is observably worse when the coil and rod are reset 90 degrees perpendicular to their original position (and incident to what could be assumed to be the predominate direction of manmade EMI). Yet the EMI doesn't increase significantly when just the coil is set vertical without the rod. Nor is it that noisy with the coil+rod 90 degrees offset but both horizontal. That would seem to indicate that the rod itself is increasing the EMI to some degree (and this may in turn cause the modulator to go less stable too), but it's not necessarily just the modulator being pushed into a less stable mode (though if that's what you say is happening I certainly believe you are right there too), but multiple things could be happening here. If it were only the modulator, we'd have observed the same effect with the coil+rod flat too. I'm not sure this experiment separates the two effects in a way to draw conclusions though. What is certain is the thing that changed is the specific orientation of the rod+coil relative to incident EMI. And this is why in an earlier post I was saying that additional EMI caused by presence of the CF rod would be a function of the position of those objects regardless of motion. This is a way to know noise is EMI in origin. Wether via unstable modulators or purely physical EM effects of the rod, same outcome. And I think that's what we saw here, unless it was a fluke. This video does seem to support my original point though, whatever the cause of the increased EMI may be: the presence of a CF rod may in fact add 2 sources of noise - one from inductive/ground/added target effects, and a 2nd from added EMI.
  4. None of the sand pits around here have free gold unfortunately. But for years I've wanted to find time to try something something like this to get a bunch of black sands, then smelt the black sands and see what comes out of them just out of curiosity. In some places further into gold country I've ran into black sands that are assaying above 6 oz/t + occasionally PGMs, which may end up working out to more than 1.333 grams of gold for 2 yards of sand, who knows...
  5. It's not really conducting electricity directly to a coil, if interference was happening it'd be due to EM field coupling indirectly, like you guessed magnetic field, but also consider the electric field too. Remember the old TV's with those touchy antennas where the reception would change if you simply put your hand or body closer to the antenna without even touching it making the reception worse or better? That's an example of coupling to fields without physical/electrical connections (as are metal detectors). You are by proxy increasing or decreasing the EMI or signal strength in the received signal at the TV. That's because in effect your body is also a conductor (like a CF shaft), and physically uncoupled conductors can still affect the electric (E) field via re-radiation, scattering, etc. Generally when we think of stray EMI, it's in terms of E field noise not M field, especially atmospherics like wind (static), lightning, sun noise, even meteorites (aka "spherics"). Powerlines are also dominated by E field components. Often the M field dominates at larger distances though. E or M can predominate in various EM radiation. What this thread has largely focused on isn't EMI from the CF shaft though via E field effects, but magnetic coupling effects. Neither M or E fields require a physical connection via wire for coupling. This is why a coil doesn't need to touch a gold nugget to detect it, and why an antenna doesn't need to touch a radio transmitter to receive the signal. There are also capacitive effects to consider, since capacitive coupling is in essence a 3rd way to interfere. Actually, in effect by defintion, the coil+plastic housing+conductive shaft is actually a real capacitor and passing it through an atmospheric voltage gradient (much more pronounced at higher elevation I think) may itself generate noise. On top of that, ignoring E field/capacitive coupling, there could also be the potential for magnetic coupling too if there is any noise/EMI with a strong magnetic component, since a conductive shaft could be viewed as a 1 turn coil, in essence. Not saying it's happening here, but it'd be worth investigating to see if there was any measurable effect I think. Ron asked earlier, but if anyone runs into a 6000-compatible non conductive shaft I'd be interested too. This machine even post-fix is still plagued with excessive spheric and other EM radiation related noise problems IMO and it'd be good to know if any part of that came from the shaft or not. The motion of the shaft relative to the coil shouldn't make a difference if so - instead the position of the shaft relative to the incident EMI and relative to the coil position should make a difference.
  6. I have to admit I didn't read 20 pages of topic on a subject I already thought was widely understood to begin with, I just scanned through after realizing it was ongoing still, to see what the debate was about and didn't see anyone mention anything having to do with the E field at all.
  7. I don't think this is just a VLF issue. The 6000 couldn't detect it's own shaft IIRC when I tested but it very definitely can detect a flat piece of CF, which I posted about a few years back trying to track down the EMI issues with it. So I don't think it's limited to VLF's, there is probably a good reason the GPZ lower is plastic. But people are only considering half the picture - a conductor can couple to the magnetic field of the coil and cause spurious signals via mechanical movement (shaft moving relative to coil). But a changing magnetic field by definition produces an electric field at 90 degree offset too, which a conductor can also couple to. A conductor coupling to this E field is called an antenna, and it can also couple to EMI and spheric-type E fields. In a way, the shaft is also a capacitor, and stray capacitance on high gain prospecting machines is a killer. The 6000 is sometimes noisy as hell in high wind, dry (static/spheric) environments that the GPZ can work well in. I wonder if it's a result of less robust noise filtering/high gains, or if part of it is E-field effects from the CF lower rod? No idea, might be worth testing though. If it did, it wouldn't be mechanical movement, it would just be added noise all the time regardless of movement of shaft relative to coil. Stuff probably not of concern to a coin/relic hunter but for prospecting every little blip and noise is a potential missed target and/or wasted time when we are listening for the tiniest of signals.
  8. You are right - there does seem to be a line somewhere where we've just gotten to used to newer performance and going too far below that in raw power seems unappealing even if there are other improvements. I don't know where that line is because I simply don't have access to a wide range of machines. But I know I would recognize it if I saw it, and I want to make sure that these machines are over it if possible. The "thing" with the 6000 that makes it special aside from ergonomics is it's small gold sensitivity. Same could be said with the initial release of the 7000, small gold and speci gold reopened a lot of places up. But the point I want to make is none of this is important with an exploration machine because it's not about reopening any goldfield up again - it's about finding new ones. All this stuff that is patented and guarded I don't find myself needing in many cases, in fact often I want to desensitize the 6000 so I'm not wasting so much time digging tiny iron and pellets. Most the new patch leads I find are 0.2 to 0.75 grams, it's easy targets. But yeah, if it's not getting 5000-type depth (or 3500, or even SD) with the same coil or something that isn't 2 steps below that, then I'd say that's crossed the line. Do you think even all these years later after the older boxy GPX's it's not possible for the next Algo or some new Nokta to just get close to 5000 depth? The patents for some of the older GPX's or SD's gotta be expired soon or already are and they have similar outright depth so it seems patents wouldn't be an issue but that's an outright guess and I have no clue because that isn't something I pay a lot of attention to.
  9. The Algoforce from what I can tell is already most of the way there at $1500 or whatever it's US price will be. I'm not expecting 7000 performance and cutting edge tech. The things I want to see are already mostly there in these lower price machines, but it's just not all the way there yet (saying that knowing I cannot physically use an Algoforce yet). The improvements I want to see aren't secret or patented. Almost all of them are entirely achievable via newer components, in some cases via standard libraries that come with the chips, but clearly are not being fully utilized until recently. Ex: the Algoforce outperforming the more expensive 6000 on EMI - EMI mitigation is not a detector specific thing, it's a universal problem with a ton of existing resources available. A lot of this has to do with speed and noise mitigation. The rest is stuff like physical design or avoiding too much opaqueness (this is what I meant by "dumbing down"). These are all things that a good tester absolutely can help a company with. But it would be interesting to know if ground tracking IS one of the patented things...seems weird if so. But I find auto tracking crucial in a lot of areas I'm flying through. A lot of experienced advice through the years has been low and slow, manual ground balance. But this is a way to be really ineffective at exploration, people need to learn to get over trying not to miss every tiny blip outside the known areas, and to look at bigger picture in those cases for efficiency, and to do that you need a detector that is amenable to it.
  10. That's good to hear, I think I remember reading your report near powerlines early on and that really kept my interest going in this machine. I don't know what it is but I seem cursed with every new place I want to explore has a powerline or cell tower installation smack in the middle. I simply cannot run my 6000 there or nearby, and thus I'm left missing a piece of the puzzle - no clue if there is gold there or not. So I end up having to spend a long time taking 1 gallon ziplock bag samples, then driving 50 miles to water, and panning them out in cow pee infested bogs haha. Really, just want a detector that works wherever I'm using it, and that means EMI mitigation, especially for some reason in the upper elevations and Rockies, no clue why. I can't even detect here in some cases when it gets too windy because of (presumably) some kind of static? No clue.
  11. Unless they can make a GPZ 8000 lightweight and adept as an exploration machine, then there is a major niche to fill among serious prospectors for an exploration machine. And that niche is remarkably close to what is already available in something like the Algoforce or the 6000 - thus my interest in this range. But dumb it down too much, and it makes it useless, which is why I wanted to voice this. It would be a mistake IMO to make a $2000 machine targetted just for low-mid level when a very similar machine could be made to cover what I truly think is the future of prospecting in exploration. I've posted about it frequently in the past, but a good exploration machine doesn't need to be bleeding edge powerful, it just needs to be light, fast (recovery, noise cancel, processing in general), configurable, robust, have good EMI capabilities, and not be so dumbed down as to make it infeasible for non-hobby use. It's remarkably close to the $2000 niche machines, the 6000, or whatever else. I use the 6000 far more than the 7000 for this reason. The only thing that would make me more interested in an 8000 than I already am on general curiosity principals is if they could make it at least as light as the 6000. My interest in the 8000 otherwise is limited to cleaning patches I find with the exploration machine, or dozer/pushes/digs type stuff. The exploration machine is 75% of my use now, and that's the 6000 currently which I am more than ready to ditch because it's too noisy along with other issues like slow recovery speed and opaqueness. I've offered to test and provide input to both Algoforce and Nokta for this reason. Neither have expressed any interest. I think that's a mistake, but of course I'm biased. 😄 Only so many times I can offer what I think would be help though, moving on and made other plans.
  12. That's good news, especially on the EMI front. I can't stand noisy detectors and they cause a ton of missed gold IMO. It's never been a main focus for the manufacturers for some reason even though we have hardware and software that can address these issues far better than even just 10 years ago. It's always been a part of my requests for newer machines, and never materializes. To me it has been, and still is the single area where the easiest improvements can be made on PI's today.
  13. I'm guessing it's cheaper to make a 6000 than a 5000 or SDC these days. Especially if the goal was to redesign those old machines and put them in modern cases, requiring re-engineering costs. They all use outdated, obsolete or overly analog and large parts. The boards would have to be redesigned to accommodate newer components, and to accommodate ergonomic form factors. A new case would need designed. At that point they are making a new detector entirely and might as well just reuse the 6000 instead and hobble it or change the timings around, a lot of which could just be done in firmware cheaply. To me the 5000 is a dinosaur. But honestly so is the 6000 at this point too - even with the EMI fix it lacks sufficient attention to noise cancellation and EMI mitigation and that would need addressed with any model that used it as a base platform. If Minelab offered some inexpensive model though I'd guess it'd be something using the 6000-type platform hobbled down and restricted, with some modifications. Way cheaper than trying to re-engineer older models into new cases from what I can tell. It's not like the 6000 costs more than $400 or so to manufacture, and that may be overestimating things.
  14. The sound of gravel clanking into the metal nozzle underwater is ASMR-like. Watching gravel get cleaned off bedrock is like visual ASMR too. Nothing really like it, but man it's getting hard to find places to keep dredging, I'm getting down to working muddy places with lots of cows that I don't really want to submerge into, and it's just not the same as a crisp clear mountain creek.
  15. Open up a public API to the detector software and some hardware functionality so we can mod our machines or just experiment with the nuts and bolts. Even just a port to access the raw data directly would be interesting, as it could be recomputed, logged, whatever. It'd be a fun way to learn more about how everything works too - that's how some of us learned how to work on engines for example despite not understanding them entirely at first, and it's how I learn anything myself, just by getting my hands dirty with something real in front of me and not a book. It'd have the potential to create a modding community and make detectors a lot more fun and personal. And who knows, someone might actually figure out something new that the limited number of detector engineers hadn't thought of yet. It'd be something to keep me working with a detector even if I have no gold or coins to detect at the moment. I don't know that Algoforce would ever do this - but I guess they seem about the closest any manufacturer has come to a company that focuses on what it's customers want rather than what can maximize it's sales by forcing us to just buy an entirely new detector every time a marginal improvement is made. I'd buy a detector like this even if it wasn't something I needed, just so I could have something to experiment and play with.
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