Another reply regarding search coil choices.
| September 06, 2021 02:09PM |
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kac
Larger coils have their place and certainly ground conditions dictate how big you can go as mineralization and emi goes higher the depth difference is much lower so is it worth swinging a 17" coil with only an inch gain if your lucky?
No argument, a bigger-size coil can have its place. As long as there is minimal masking trash and the coil size isn't 'too large' as that can impair detection depth and responsiveness to smaller-size (coins, etc.) targets.
I compared a lot of bigger-size coils back in the latter '80s, and again several times in each decade since then, using controlled testing, very mineralized ground, and search coils from round-shaped 10" diameter up to 16" diameter, both Concentric and Double-D, as well as odd-shaped coils in that range. What I found was that, depending upon the brand of coil and detector, and the detector's circuitry design, as I increased the search coil size on an assortment of US coins (thus testing with non-ferrous targets) I found that there were slight increases in detection depth and signal strength / responsiveness to smaller coils with 10", 11" and 12" dimeter coils.
When I got to the 13" and 14" dimeters I started to see a maxed-out or limited detection cut-off on smaller size coins, but did see a few acceptable responses on the lower-conductive US 5¢ coins with a moderate to higher-frequency detector, or a somewhat acceptable response from larger-size higher-conductive coin, such as sometimes a 25¢ but usually a 50¢ piece or $1 coin when the detector was operating at a lower frequency. Usually, the 14", 15" and 16" coils produced a little less detection depth on coin-sized targets and were better suited for searches going after larger-size metal targets.
Since most of my hunting is in very trashy environments with a lot of brush and ferrous debris to del with, I rely on smaller-size coils, opting for a mid-size for 'fringe-area' searches or 'scouting' unknown areas. I do keep my biggest coil, the 8½X11 'Raider', on my 2nd Garrett Apex for open area hunts.
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kac
In the North East here grounds vary but in general open areas you can do well with a >13" coil. Get into higher trash then certainly the little coils will pick make isolating targets easier.
"Out West", where I have hunted most of my life, from the Pacific coast in to the eastern borders of Colorado, ,New México, and Wyoming (I've never been to or hunted Montana) , I have encountered a lot of ground mineral environments from 'pleasant and kind' to downright 'tough and challenging', especially in the very mineralized chucks around Oregon, Nevada, Utah and Colorado. In the 'Central States', such as Kansas, Arkansas, Missouri, Nebraska, Oklahoma and Texas, or the 'Back East' states I've visited, to included Florida, New Jersey and New York, I have sometimes worked a few more mineralized environments, but also a whole bunch of 'very friendly' dirt to deal with.
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kac
High iron areas I fall back to the concentrics though the 2 I have are same size, 8x9 on the Tesoro and 9 on the Kruzer, both do the job and won't mask out on me. Other than that I typically use a DD.
Some detectors were really designed for and to work with a Concentric better than a DD or with a Double-D rather than a Concentric. A few can do reasonably well with either, and of course some models don't have a Concentric coil made for them these days. In the very challenging ghost towns and cellar hole areas I work out this way, that have a lot of Iron Nails and associate chards of Rusty Tin, my Nokta CoRe and Relic do pretty well with their smaller-size DD coils, and my Apex handles them reasonably well with the 'Ripper' DD, but I wish I had a 4½" to 6" Concentric coil from Garrett for the Apex. My two Tesoro's, with heir 6" Concentric coils, handle the conditions pretty well.
I don't have a problem with the Single-Tone Tesoro's, or the 2-Tone of my CoRe or Relic, and if the debris is mainly Iron nails, I prefer 2-Tone. But for an assortment of mixed-up debris in very tough places, I like the up-to 5-Tone of the Apex and 3-Tone with my CoRe and Relic.
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kac
Today I hit a field that was just cut. Buddy mine did very well last year there and found some nice old coppers and some v nickels. Place has been hit hard, lots of old iron bits and chunks of coal as back in the day they used steam powered tractors in the fields.
Weather we had a chance of showers so I used the Kruzer with 12" coil (similar depth as the Nox 800 which my buddy uses). Hunted in Gen Mode (all metal) and just listened to any obvious rises in threshold and payed attention to the size of the sound then checked id's. Often I would get a 4 (iron) and sometimes just a - - so I would flick to 2 tone and squeeze out a number. I won't hunt in 2 tone as it is tough on the ears and not nearly as informative to the target as Gen or 3 tone).
I envy you getting onto a fresh-cut field. I do miss the farm fields I used to enjoy up in Oregon, and I wish you the best as you continue to enjoy hunting them.
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kac
Long story short I managed to pick out a nice little turn of the century button, thought it was a bell button but it turned out to be just a small button, piece of a harmonica, little brass clasp of some sorts and the pendant that is gold plated.
Back of the pendant refers to the a carriage company that lasted a couple years. Not sure how old the pendent is but definately not a common find. Sometimes not finding coins and coming across something old and unique is just as fun for me.
Thana's for the photos, and let's home a nice old coin or two will show up on a future visit.
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kac
Weather depending may take my Tesoro out there and see what I can sniff out and yes it will be with the bigger coil
As a Tesoro fan I'll root for it to serve you well today .... even if it does have an over-size coil mounted.
Monte
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