GB_Amateur

Now that's a tease if I ever heard one. It really is fun sharing, and learning from your detecting partner in the process. Doggo and I did that a couple weeks ago. Oh, and BTW, we both found silver!

The hardest I am on coils is when the grass hasn't been cut for quite a while and I try to get my coil as close to the ground (soil) as possible by forcing the coil through the grass. (That's hard on my elbow, etc. and I pay for it later....) Still haven't broken anything, though. I do wonder if salt water has a deteriorating effect on the plastic. But if that's the case, wouldn't it become noticeable on other water detectors? Here I'm assuming manufacturers use the same plastic resin, so that may be a difference. I recall Simon (Phrunt) posting the idea of using spray on silicone as a lubricant for the rubber washers. I took him up on that idea and it works well for me. I don't like my coils too loose but I definitely want to be able to change the angle (coil-to-shaft) by pressing the coil to the ground, not having to reach down with my hand to perform that. The silicone facilitates this technique still without requiring over-tightening. Another issue for me is the screw/bolt and nut. Seems like every manufacturer (and sometimes every model made, even by the same manufacturer) does it differently. I prefer the standard screw and wing nut design (ala White's and Coiltek, for examples) as opposed to the closed nut method as it's too easy for the latter to get loose without me noticing (and then, on a bad day, fall off and getting lost). I wonder if the exposed threads outside the (open) nut is a concern -- vulnerable to getting dirty with the result of the threads getting munged up when the nut is removed (without first cleaning the threads). Here I like to use another spray on lubricant ('teflon' type). And I wish more manufacturers would use common screw and nut products that you can eassily get at other outlets, for a reasonable cost, rather than a custom version they then sell for an arm and a leg. (I know, bitch, bitch, bitch....)

I dig about half dozen of those in a 3-4 hour session. Shallow ones are loud (but so are shallow pennies...) and I get a surprising number of deep aluminum screw caps. I chalk those up to my nemesis -- landscaping backfill. But a couple Al screwcaps per hour really isn't much of an annoyance, for me anyway. Zincolns on the other hand....

What was the dTID on the Indian Head? My 95% copper (small) USA cent finds go all the way from 19 to 26 (ML Eqx with 11" coil, mostly hunting in Park 1, RC = 4, F2 = 0). I think corrosion from ground minerals is a key factor for copper alloys, but I still need to do some tests with the hundreds of Wheat cents I have (specifically those not found with a detector) to see if there are other hints/clues. Since I dig every small sized target above the Equinox dTID of 21 (and many in the 19-21 range) that doesn't have strong ferrous dTID content, I don't go out of my way to nail the dTID before I recover. It does seem that silver dimes center a bit above where 95% copper cents and clad dimes do.

Should be the same as the Mercs you've found. Composition, size, weight were the same from 1873 through 1964 (and you can go back to 1853 if you ignore a weight difference of 0.01 g). Before that they were 2.67 g compared to 2.50 for those most recent 90 years. I don't know if wear has an effect, but my guess is that it would require a significantly worn (underweight) coin to notice. I'm talking one where you can hardly recognize the images on the coins. That IHP tells you what you want to know -- people have been dropping coins there since at least the early 1950's. Persistence (something you obviously have) hopefully will eek out at least one silver coin.

Glad you pointed that out. Measuring volumes is rather in-exact. Much better is using Archimedes Principle but even then you need a scale which is quite sensitive relative to the weight of the object whose density (or specific gravity) is being determined. Many common elements and alloys fall in the ~8-9 region of specific gravity so a 10% error in your measurement value of 10 could mean your find is among those.

There are two ways of thinking about conductivity -- one is the purely scientific and the other is how objects respond to a metal detector. In the first case, the fact that a pure (elemental) metal has a particular conductivity doesn't mean that its alloys will be similar. In pure elemental form, the best conductivities (at 'normal' temperatures) in order are silver, copper, gold, aluminum. At water's freezing point temperature those conductivity values (in units of 10^8/ohm-meters) are 3.3, 0.64, 0.49, and 0.40. Pure platinum is a bit worse than pure iron: 0.10 vs. 0.11 and ranking 22 and 21 among all elements found on/in the earth. Lead is another well-known metal (not always found alloyed) among detectorists. Its conductivity in pure form is about half of iron's. Alloying small to moderate amounts of a secondary element (usually done to make a metal more durable) typically drops the conductivity of the dominant element. Different shapes, sizes, and amounts (i.e. weights) changes things, and in the case of jewelry, often drastically. Best is for someone who has found platinum jewelry to indicate where on the typical metal detector conductance scale those show up. Relying on scientific measurements of pure elements when trying to figure out metal detector response isn't really very helpful in practice.

Could it be an urn? (You didn't mention what was inside the inner container, if anything.) Appears to have been made on a lathe and the symbols appear to have been made with an inlay technique called marquetry. Probably has an early 20th Century origin (maybe late 19th C.) and not native American. I along with kac and locator also doubt it has anything to do with Nazi Germany.

The condition of that thimble is impressive. I've seen antique thimbles in which some of the dimples have become holes. Needles can be forced through the metal and years of use can lead to that. Yours looks pristine. Maybe it was a display piece for the owner, or possibly it was lost shortly after being acquired. Either way you have an artistic but utilitarian item made of precious metal whose condition is nearly as high as it could possibly be. Thimble finds don't get much better than that!

I think you are right that the patent includes frequencies up to 100 kHz. However, some people have measured (and reported here) what frequencies the Equinox 800 transmits in simultaneous multifrequency modes. The highest frequency I remember anyone measuring was right around (actually a bit under) 40 kHz. Minelab could make some of our lives a bit easier but it's understandable they don't want to reveal proprietary information. Besides, for practical purposes "the proof is in the pudding."

Even if possible without a hardware upgrade, would it make financial sense for Minelab to execute such a 'free' change? Have they ever made such a significant change via software upgrade? From what I've seen over the last several years, they don't even add new coil options and seldom do they allow aftermarket coil makers to do that. Doesn't the 25+ year old Fisher Gold Bug 2 still the have the highest operating frequency (option) of any ground balancing IB detector? If Minelab were to develop a detector for which a 100 kHz ground balance capability has significant application(s), would they even include it first as a selectable frequency option on a simultaneous multifrequency detector?

Does most of the East Coast east of the Appalachians (obviously not Florida) have clay below the topsoil, within detecting depth? Unfortunately, here when they backfill it's done with clay. Sometimes they even remove the topsoil to sell and replace with clay! Greedy %^*)@$&*! At my recently discovered park where I've been finding Wheats, the other day I dug down 11" through clay to find a vertical nail or wire (stuck too tight to remove and identify). One positive result of their sloppy relandscaping -- grass doesn't grow as easily in clay so the ground cover is mostly weeds. I don't feel as guilty when my recovery methods during dry season end up resulting in dead weeds.

Check out this: http://www.coachbuilt.com/bui/h/hume/hume.htm

Just checked mine. Since start record-keeping (beginning of 2017) mine is 7.8 Wheats for every silver dime. But my lower counts lead to larger uncertainties so with 95% confidence it's between 5.4 and 10.2. Do you ever ignore dTID's above Zincolns, assuming they sound like good coin candidates? I know some claim they can tell a silver dime from a clad dime or copper Memorial and I don't doubt there is some separation under the right conditions, but I've always erred on the side of not getting too hung up with trying to dig only the best targets. For example, I dig a lot of aluminum screw caps which dTID right where most of my Wheaties hit. My ear isn't good enough to distinguish between the two, other than possibly cutting between loud ones (more likely screwcaps) and faint ones (more likely Wheaties). In my case there aren't so many of those trash targets that digging them overtaxes my time allotment.

Nice haul there, as always. Your "month or two" is more like my half year, and I'm probably putting in more hours since I have less responsibilties leading to more time to detect. But quality (skill) tends to beat quantity (time). Glad it's not a competition. 😉 A significant difference (and there are likely quite a few others) between your sites and mine are the number of hours they've been detected previously. One would think that would be to my advantage, but it doesn't seem so obvious, especially with your results. (Many more variables leading to those result comparisons, though.) Regardless, you give me hope that there are plenty more worthwhile targets in my ground, I just have to figure out how to find them. BTW, are the pennies in that pile (LH of the last photo) all Wheaties? I assume so since the only reverses I see are Wheats and I don't think you'd mislead us by making sure all the Memorials are heads up! If so, can you give us a silver dime to Wheat penny ratio? (And I'm assuming you don't ignore either of these targets, even if you can separate them by dTID.)

I forgot to include a few more pieces of info that may shed light on my experiences so far. 1) Regarding detector and settings, my usual park and school 'rig' -- ML Eqx 800 w/11" DD coil in Park 1, no notching, 5 custom tones, Recovery Speed = 4, Iron Bias F2 = 0, ground balanced and EMI cancelled. In heavily detected sites I usually go with gain = 24. Here I turned it down a bit to 22. 2) I mentioned some similarities between pre- and post-park aerial photos. Where currently there is a concrete block restroom building (men's and women's sides plus a central utility/maintenance room), back in the 1950's (as far back as the photos I've seen are taken) there was a different building the same location. It's about twice the size and had a hip roof. I suspect it was some kind of office for the industrial site. The park itself is rolling hills/valleys along with several flat areas. The building is on a high level spot but right behind is a slope down to lower ground -- an obvious place to sit and eat lunch, drink beer, waste away the time now. But was this also a spot where the workers lounged during lunch and breaks and after work? There are trees there now but too small/young to have been there 50 years ago. Aerial photos are often too fuzzy (and sometimes taken in the winter) to figure out where the trees were back then. 3) Besides the building, there are two other landmarks which appear to have commonality between the 50's and now. One today is a circular sidewalk with exercise equipment inside. There was something of similar size and shape there in 1965. Where today is a baseball field, there is a ghostlike field of similar size back in the 50's. 4) For the most part the recovered Wheat pennies were not deep. Of the 14 found so far, one was about 7" deep, one 6" deep, most 3-5" deep and one about 2" deep. Always something I try and figure out is whether or not a site has been detected previously, and if so, when. This one has me baffled. Who doesn't dig high conductors which are shallow? Am I the first one to hunt this park? Hard to believe in 2021 that an easily noticed (at least on maps) park has never been hunted. If so it's the first I've found. Another minor mystery is "why so few nickels?" If the Wheat pennies are representative then there should be an occasional Buffie as well as an early Jefferson or two. I'm hardly finding any nickels at all, old or new. Plenty of clad dimes and quarters, at least compared to my typical park/school detect. Also, pultabs in the nickel range seem to be on the sparse side. That would make sense if this site didn't see traffic until after the ring-and-beavertail era (1965-75) which is consistent with the 1974 date of the establishment of the park. I tend to stay away from parks on weekends (especially holiday weekends). This week looks like nice detecting weather so I should get over there at least a couple times during the upcoming workweek. More evidence will show up, it's just a question of whether it will help solve the mystery or simply add to it.... And I want to prove Raphis wrong as to whether or not I'll find a silver dime.

It seems one of my recurring detecting New Year's Resolutions has been to find new hunting grounds and not get stuck in a rut trying to find the last crumbs I'm capable of tasting in the sites I've detected extensively. So far this year I've done well (at least one silver coin in each) at three 'new' sites (two parks and one school) and 3 weeks ago before heading out East I was able to get in a short 1 hour hunt at another park I've never previously visited. I vaguely knew about this spot previously but for various reasons I never tried it. My first 'requirement' is that a new (to me) site have a decent chance of hiding old coins. For the most part that means having had significant human activity prior to 1970 and preferably prior to 1960. This 4th 'new' (to me) site of 2021 didn't seem to meet that minimal requirement. In fact there is a prominent bronze plaque on site which states it didn't become a park until 1974 and previously was an industrial storage lot for several decades. However, Historic Aerials hinted at a more promising past. It seemed to show that some of the modern park's features were present at least back to 1965. I'll go deeper into that later in this post. That first 1 hour hunt produced three Wheat pennies along with four copper (alloy) Memorial Cents and a couple clad dimes. Three Wheaties in an hour on a site which supposedly wasn't frequented until 1974 was surprising but far from earth shaking. I filed it away until after getting home from my week+ in the East. After getting home I needed some time to decompress (i.e. take care of other things) and it was quite humid besides. Further, this summer has been wetter than normal and the grass grows back as fast as it gets cut. Finally this past Thursday (2 days ago as I write) I got in 3 hours on a freshly mown park. I concentrated on areas that the Historic Aerials indicated would be most promising but still did some fairly broad surveying. The results were a bit disappointing compared to the previous short run -- 1 Wheat cent vs. 4 copper Memorials along with a few modern 5, 10, 25 cent coins. Here's a photo of only the coin finds (oh, plus a Sterling ring my wife has already claimed): The next day I returned for another 3 hours, this time hunting exclusively on what I considered the most promising part of this site. Now the floodgates started to open: 10 Wheaties compared to 5 copper Memorials along with $1.85 in larger denomination modern coins: The dates on the 10 Wheaties are: 1909, 1918, 1920, 192x-D (haven't yet resolved that last digit), four from the 40's and two from the 50's. Non-cent finds don't seem to show any particular date pattern although only 2 or 3 are from the current millenium. Now for the non-coin finds from these last 2 days (total of 6 hours): Pretty much the typical park trash. There is one arcade token from 80's or later (right below five Stinkin' Zincolns). The ladies watch appears to be nothing special (no precious metal or stones). Possibly most interesting is above the drink can lid -- it's a copper piece that looks like it has a coin slot in it. The padlock is badly corroded and the shank has been cut with a hacksaw. It may be from this site's industrial days. Oh, one last interesting find. To the right of the Hot Wheels car is a wooden piece I recognize as being from a Lincoln Logs wooden playset (not metallic)! So what explains the plethora of Wheat Cents? Here are some hypotheses: 1) The bronze plaque is wrong and the property was turned into a park well before 1974. This seems a bit odd -- I mean the park department historian can't get a date right and spends hundred+ dollars on a sign with erroneous information? 2) The industrial site's employees spent some of their lunch-hours in the same shady(?) sloped spot, either accidentally dropping coins or even possibly playing some kind of penny-ante game tossing them and missing picking up some? 3) Nature's randomness is conspiring to try and trick me into thinking this site's Wheats/Memorials ratio is indicative of something other than just luck. The plausibility of this last hypothesis can be tested with statistics. I'll start with my on-going 5 year record of fraction of copper Lincolns that are Wheats. That's 338/1547 = 21.58%. Most of these have come from parks and schools, all of those sites having been established no earlier than 1974 while most of the remaining sites were private permission homesites that were established no later than 1960. Thus using this value as 'typical' for sites frequented for at least 47 years is a stricter requirement than necessary. Still, using 21.58% ratio of Wheats to total coppers, the chance that of the first 27 copper alloy Lincolns found, 14 or more would be Wheats is less than one in 7100. Of course Wheats tend to be an indicator that even better (yes, silver coins) treasures are hidden and awaiting a coil to be swung over them. Hopefully I can add some more evidence by digging one (or more) of those on my next trip to this spot.

And that brings up another quirk of the White's TDI family. I've read (but have no personal experience) that although Mono coils made for the Minelab GPX (don't know about other GP's) work on TDI's, it wasn't necessarily the case for DD coils. (The Platypus is a Coiltek made for Minelab detectors, right?) Did White's or Miner John (=Razorback) ever even make a DD coil for the TDI? Seems like I vaguely remember a Miner John DD, but unfortunately their facility got wiped out by California weather 3 or so years ago and that was the end of them. 😪 Coiltek made coils which were explicitly specified to work on the White's TDI's. Did they ever make one of those that was a DD? As to relevance of this post to the thread, the fact that the Coiltek Platypus 12x8 DD didn't perform well on the TDI may not be relevant for how well it will work on a Minelab GP Extreme.

There have been several threads here on this topic. Some kind of search should find them. The late Reg Sniff was the guru of TDI mods and he posted quite a few things here, as well as other forums and possibly hardcopy publications. I recall there were different versions of the TDI/SL and that some mods work for some and not others. So I don't think every garage mod works on every TDI/SL. I also recall Carl Moreland (who had a hand in its development at White's) warning against too high of a voltage but I don't remember exactly what his recommended threshold was. That would be a good thing to look up. I also modded a battery pack with an external 4-pack to be able to run 12 AA cells in series. I bought some dummy batteries (basically shorts) so I could choose 8, 9, 10, 11, or 12 cells in series. On top of that I did this specifically to use NiMH rechargeables which, very soon after having been charged, come down to ~1.4V; thus 12x1.4V = 16.8 V which I think is below Carl's max recommended potential. (NiMH's have a gradual decay falloff of 1.4V-->1.2V which is their nominal operating range so typically they aren't even as high as 1.4V for long.) If I recall (and don't trust me on this but better to read all the posts), my TDI/SPP was a version which couldn't be helped by increasing the voltage. There also was some discussion (disagreement?) as to whether running with Ground Balance set to 0 (off) would improve depth. The consensus was that it would and that certainly is the case with my /SPP. But because of the different factory release versions maybe that was also dependent upon the particular version -- IDK....

Well, there you go. Not only is the Wilson detector not from Europe, it's from my home state! In fact the first coin I found (that with the Heathkit GD-48) was less than 100 miles from South Bend. One of the great things about this site -- always something new to learn. Thanks for the answers and details of your detecting philosophy.

I like these surveys so kudos to you, locator, for creating this one. I do see a couple (minor) deficiences which I'll quickly point out and then procede to my details: 1) 'fun' and 'success' are two different things and I have different answers (see below). 2) Fisher m-scope specifically? All other Fisher detectors go under 'misc'? And who/what is Wilson (besides a huge sporting goods company)? Is that an early European brand? "You always remember your first..." leads to my 1st and 2nd in the 'fun' subcategory: Nothing like the fun of finding your first 'treasure' (early Wheat cent in my case) with a detector. That's the Heathkit GD-48 which was a DiY assembly project (that I screwed up by getting a diode in backward 🙄). Was still in high school ~ summer of 1970. Hammer (head only) shown in photo was also a find which I still use today. 2nd most fun (I won't include photo since it's well known) is the Fisher Gold Bug Pro I bought in August 2015 and proceded to find my first silver coin, first Indian Head penny, first gold ring, and first Civil War relic (button), all with the 5" round stock coil. I was digging it all back then (except low conductive ferrous) -- those were the good old days. Most success easily comes from the ML Equinox. Part of that is because I have by far the most hours with it. It's my detector of choice with others relegated to the 'specialty' category.

Nice writeup, Chase, and thanks for sythesizing (translating?) for people like me who aren't as tech saavy and/or up on the latest ideas/products. I've quoted a couple (IMO) key points and highlighted the most relevant. Regarding latency of current detectors (this isn't just limited to Minelab products, but Garrett for sure, and I assume XP and others), APTX-LL was never as fast as those (I think the proprietaries are in the high teens of milliseconds). To make matters worse, some advertising promised or deceptively hinted APTX-LL when the products didn't meet that spec! There has been debate (which I doubt will ever be resolved) as to whether detectorists can tell the difference between latencies of 40 ms and 18 ms. I happen to fall on the side of 'yes', but a well thought ought and conducted experiment would need to be executed to find out the real answer and I have no interest in going to that much trouble. Still, technology in general tends toward faster,better,cheaper so it rubs me a bit the wrong way that there is the faster method isn't being exploited in most of the real world. And this is where the reasons my second quote & emphasis becomes clear. The 'public' didn't buy into APTX-LL because listening to music (what 99.99% of Bluetooth users do?) isn't affected by latency. We detectorists are a mosquito compared to that elephant. I seem to be in the minority of preferring the detector manufacturers' proprietary methods. I use the WM08 exclusively on my ML Equinox 800 and I use the stand-alone (proprietary) Garrett Z-Lynk transmitter+receiver for all my other detectors. As long as detectors include an industry standard external jack (1/4" or 3.5 mm) and as long as high quality 'wired' headphones and earbuds are still available, I'll be fine. Would I prefer fewer wires? As long as they have the extra-low latency (Garrett's Z-Lynk system is the poster child) then that would be even better than my current setup, but I don't mind the hybrid (old fashioned headphones with cord connected to a receiver that fits in my pocket). The main thing is I'm not tethered to the detector. Being tethered to something in my pocket by a cord from my head to that pocket isn't a big inconvience for me.

Glad you got through this without major damage, D.; sorry your neighbors got it so bad. Another bad year for the continental USA with wildfires in the West and flooding in the East. The peak of hurricane season is just arriving, so it's far from over. I was surprised how much energy Ida carried for such a long distance. I heard on Weather Channel that the Gulf Stream added considerable punch to the storm when it got back near ocean (East Coast). It's bad enough when storms hit sparsely populated areas but when they make it to dense population as Ida did in New Orleans, DC, Baltimore, Philly, NJ, NYC, Connecticut,... the misery and devastation goes up by an order of magnitude. 😪 Parts of Europe have been particularly hard hit this year, too, as has Haiti (hurricane and earthquake). We're not alone but misery doesn't love company in this case.

Is it possible you bumped some calibration adjustment controls? Did you verify that the pots you cleaned were subsequently giving the proper range of resistance values?

Welcome, Mario! We're always glad to get new participants, but "members with benefits"? That's a new one. You beat me to that question, kac. Schematics can be worth their weight in gold. (OK, they're pretty lightweight...) Maybe some of these are already floating around from reverse engineering tricks. But getting schematics out of detector manufacturers is harder than getting gold out of Fort Knox. (Well, at least for us regular citizens.)