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Geezer

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  1. That may be the right way to go. I have asked him about the quarters before, but did not get anything useful. Whether or not I understand why is less important than simply getting the targets, and getting them in well hunted ground. Clearly masked targets to my mind. Perhaps understanding more will add nothing more to it. It is an interesting thing to think about is all.
  2. My reason for posting this at all to see if anyone has ideas on why the TID shifts like this. We know that the large coil can shift it, salt balance and black-sand maybe, ground balance shifts it, and probably more. But why some coins, and especially some coins at some places shift given the settings as more or less a constant for me. The coins are always heavily discolored and sometimes crusty too, if that might matter. Not sure how to ask the question properly, but the TID shift I am asking about tends to be in places where the junk is high and often some bad soil or EMI too. There always tends to be a lot more quarters than are ever seen in areas without this effect. Clearly these coins are masked from other detectors, but I do not know why. High trash areas seem to be where I have the best luck anyway, probably because fewer people like to hunt in heavy trash. There is always masking in such places and it seems like one of the effects is that unmasking creates this shift. I also use the large coil in heavy trash which puts more junk and bad soil under the coil at any given time too. Just thinking that any sense of why might allow a more effective setting profile based on a specific site rather than a fuzzy general sense of what seems to work most of the time.
  3. Black sand and Salt balance are useful to help deal with junk, I use them all the time. Maybe something there. The large coil shifts the TID a little too, no way I am taking that off. Exactly. All the good stuff is round or signals hard for some reason. I found a little pendant yesterday that had broken off it’s chain. A tiny silver elephant but still signaled hard even though the shape of the sound was not clean edged. Had to dig that anyway because it sounded like one of those lattice rings. A lot of noise for such a tiny thing. I run mixed mode all the time. For what I do it helps. It gets a little chatty in heavy junk of course, but when round comes around it is hard to miss. Here you both see the essential thing to my thinking. Good targets sound good. Running through heavy trash with a large coil, the audio is the best thing to sort out what might be good from what is probably bad. Might and probably do not seem like the pinnacle of certainty, and of course it means digging pennies that sound like dimes and pull tabs that sound like gold rings, but it does allow hunting in heavy trash better than anything I have tried before. I still would like to know what shifts the TID so much some places.
  4. This is a thing discussed before, but I forget where. Today I was out for a little while and found a most unusual amount of quarters and dimes. The TID of these things was all over the place, meaning that there was no usual TID number for anything, but they had a nice clean signal. A lot of pocket change in general today, which is usual, but an unusual amount of quarters and dimes with no consistent number but had good signal tone. This I have seen many times before, but have not ever had a good explanation for. The Christmas money for my girls is mounting up. These are easy targets for any detector, and not usually passed by anyone. Of course lots of people ignore zincolns, but in well hunted areas it is rare to see so many quarters and dimes. Nickels I expect to be there because they look like pull tabs usually, but the Tarsacci loves round and I dig everything not obviously iron that sounds good, so I get them often. My theory of this is that something in the ground matrix, or in the state of the coin from being in the ground awhile, changes target ID enough that they are not properly identified by the detector for what they are. I would love to hear the thoughts of others. I see this regularly. I find no setting that returns these to their usual TID without losing trash suppression. Thoughts anyone?
  5. True enough. Just did not think the edge sensitivity was quite that much. Of course it is true that the coil is sensitive all the way around, like above the coil too. It will sound off under swings every time and the chains are a couple feet off the top of the coil. The harder part is knowing what it does not sound off on. What is completely masked is an unknown unknown of course, but looking at how far the coil will signal on really large metal creates a new unknown that is harder to wrap a mind around. This may be the trouble going around those large field light poles. That is a pretty big hunk of metal, and comes with underground power cables too. Too close to those, actually not very close at all, is tough to deal with. Though it is easier to see what the problem might be, the problem remains. An interesting topic.
  6. Today while out at a ball field I paid closer attention to how close I was getting to the chain link fence with the edge of the coil. I see my estimates are way off, and it is more like a foot where even the side of the coil signals. Much worse than I thought, even at very low threshold and sensitivity settings. Sorry about that Chief.
  7. The MDT will hunt and signal targets to within about 6-8” of playground equipment, and 8-10” of aluminum chain link fence. Approximate is about the best that can be said about that stuff because how these things are anchored varies a bit. It of course does much better if the power and threshold are both turned way down. Setting to hunt even moderately hot, you will need be out considerably further. This could cost you, hunting as close as possible to the structure of your site gives advantage. Not exactly the strong suit of the Tarsacci. A person can turn the nose pointed right at the stuff (90 deg) and moving it or walking the fence with it in this orientation allows about as close as you will get with the MDT coil. The most sensitive part of the coil begins about 1-1.5” back from the tip of the nose, so you snug up a little better if good targets are hanging there. Deep targets will still be masked by the big iron anchors and aluminum fence, but good shallow targets like coins will come through anyway. You can pick them out even of it is noisy. On ball fields, you care more about what is where the folding camp chairs get put than tight to the fence. On the ball field fence you want to be next to the fence on the player’s side. People lean with their arms on the fence and hands hanging over by first and third. For next to the playground equipment, a Compadre with a little coil will beat the pants off you. In my experience, the stock coil does not beat the 12” coil for this. I get better sensitivity at minimal settings with the 12”, and stability too. I swear the round coil does better for jewelry and coins on edge by far. What I do not get with this is better specificity. I will make the trade off, I find more with it, even in bad ground. It can be a little noisier sometimes, I am ok with that. I note the round coil there because I believe that is what makes the difference in these coils. Very little more ground is covered with the round coil, even though more ground is under the coil at any given time. It just is not that much longer so you only get a little more new ground on a swing. To my mind, the round shape matters enough to be worth the weight penalty.
  8. Thanks for this contribution RunningNorth. As JCR notes, there is an unexpected application there for this. Also it may help explain how the Tarsacci behaves in some situations. I had no idea it might be picking up big metal anything like that far away, this is good to know.
  9. That is pretty hard scrubbing to wear out coil covers like that, and a pretty hard work ethic in action too. Is the coil cover even necessary when you use the marine epoxy?The epoxy seems an elegant solution by itself, endlessly renewable and not so expensive.
  10. The same for me. I try and learn something from every thing I dig. The trash is less now than before, those discolored coins more. The larger coil seems to help quite a bit, which is the opposite of what I would have thought. That larger coil changes the TID numbers of coins, and the unmasking strategies skews them more, and picking out those on edge or masked coins creates a wider range of TID, and more I cannot think of right now, but, it is pulling those coins. In a lot of cases these are left behind because they are masked and missed. Or so I think. I find a lot of quarters and dimes that look like those nickels. I expect to find those nickels, they hit like a pull tab. Dimes maybe fall in penny range sometimes, so some might not dig the penny signals, but quarters left intentionally is a little harder to see. Running through the trash digging these things is sort of fun all by itself, just for the challenge. I have bit too often on iffy signals too. Less often now though. Good targets sound good and hold steady on a Tarsacci, no matter what the TID says. If it is not iron and hits good, I give it a serious look. Like you, I think anything that shows even intermittent negative numbers is likely to be junk. Just that saves a lot of digging. The 12” coil seems to work far better on coins on edge. I know this because I use a pinpointer to locate them, then probe with a brass probe. RIngs and coins on edge will be hard to find with a brass probe, but the pinpointer says it is there. Often they are not even very deep and can be pulled out by fingers pinching, but coins on edge like crown caps tend to pinpoint off center of where they actually are and have funny signals. This may be partially responsible for the skewed TID, or maybe not, but they are sometimes surprisingly far away from usual TID and pin point location. I get pickier all the time with the signals I dig. Of course I will miss some things that way, but I enjoy it more and spend less money on Chiropractors.
  11. Yet you make finds. That is good work, since there are few recent drops you rely on unmasking to make your finds. This is exactly what I am attempting to learn. Keep talking.
  12. Despite the variance in TID, the Tarsacci is very very good at telling iron from everything else. (Except for the wrap around, but that is usually easy to spot.) The specificity in nonferrous can be poor, or at least appear so, but it is the iron unmasking that really sets this machine apart to my mind. It is the ability to see through some iron and foils that matters to me, then ID the iron, then take a best guess on the rest. Pull tabs are still going to be a pain, and even more so when coins are not hitting where they should.
  13. Dancer, That is a lot of nickels, very good work on your part. Interesting that you note how the TID is skewed. I see this in a lot of coins that have been in the ground a while and are very discolored. I wondered if they might be close to iron that causes so much discoloration and TID change, but the TID can be quite a ways off on them. I also notice that the harder I work the settings for unmasking ability, the more untrustworthy the numbers are, even at pretty shallow depth. It brings in a lot of those discolored coins though, so it is hard to know if it is the settings or the coins in proximity to trash that does it. Seeing you hit those stained nickels with numbers out of range also makes me think it may not be the settings but possibly something to do with the coin in the matrix. The TID is usually higher in 18kHz for sure, but not that much higher and not that variable. (Well, that is conventional thinking anyway.) The harder I work at unmasking the worse the TID becomes, you here show what you miss if you ignore out of range signals. Good report Dancer!
  14. Kaolin, Now with some time spent experimenting in the field with the frequencies, 6.4kHz seems superior at unmasking coins. I am finding clad that has clearly been in the ground a while, even at sites that get hunted a lot. I had previously preferred 9kHz in junky ground and 18kHz in clean ground, but am doing better with 6.4kHz in challenging ground. Keep up your good work. Geezer
  15. Dewcon and JCR, I could not agree more. Given what the MDT shows as strong suit, it would seem to make little sense to compete head on with something like a Deus II. I still liked that two (or more) tone AM mode idea though. You could build a whole detector around an idea like that with the MDT as a foundation. If the audio were good enough, what else would you need?
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