Tony N (Michigan)
Active member
Thanks for the tips, Charles. I understand about sweep angles and masking of coins. Good to know about letting the soil dry out. DIdn't know that.Charles (Upstate NY) said:Tony N (Michigan) said:Charles (Upstate NY) said:Tony N (Michigan) said:
Depends on your soil but a gain of 7 is a good target. Think of Gain and Sensitivity this way...Sensitivity turns your depth up and down, Gain turns your volume up and down. If you reduce your sensitivity it may eliminate a deep target BEFORE gain has a chance to do anything because the Explorer first applies your sensitivity setting to the signal. If you lower your sensitivity too far you can crank your gain to 10 to no avail because the deep target has already been eliminated by your lower sensitivity setting.
Also as a refresher, the Explorer transmits at max power no matter what your settings are. You can't for example dial back the transmit power by lowering your sensitivity it doesn't work that way. Since the Explorer transmits at max power always, regardless of settings, any signal received back from a target, mineralized soil, will be the best possible signal the machine and coil is capable of. Its fundamental to understand this so that you know what you are doing when you change various settings on your Explorer.
So the machine receives the 'whole' of the signal back from the target, now with your settings you will filter, slice, dice, and carve up that target signal. Reducing sensitivity begins chopping off the faintest, weakest part of the signals, deep faint targets may get sliced off if you lower it too far. You can practice this in the field on real targets in the ground. If you get a deeper target rather than rushing to dig it, take advantage of the learning opportunity. Begin lowering your sensitivity, at some point the target that may have been a solid hit will begin breaking up and eventually vanish altogether. Depending on the target and depth a target can vanish surprisingly quick. What may have been a solid hit with the sensitivity on 28 will begin breaking up at 25 and vanish at 24 or be so broken up it wouldn't have been something you would have noticed or dug. You can do similar field tests with Gain.
Thanks Charles.
I have a question concerning old square cut nail littering my driveway. They are about 3 or so inches down. If I lower my sensitivity, and used a smaller coil, would the lowered sensitivity cause less reaction to the nails to help find the elusive coin that may be near the nails?
If, say, I crank up the sensitivity all the way but the detector is still stable, would this cause the detector to be more overwhelmed with the iron nail than the coil?
Or, as you say, the detector puts out the same transmit power no matter what sensitivity setting one uses, does that mean the iron nails will overwhelm the masked coin no matter what sensitivity setting I use?
Man, this is getting complicated! But it is a needful lesson!
Lowering sensitivity will do little to nothing to quiet down rusty nails, your average square cut nail is a huge target. Using a smaller coil (I like the Minelab 8 inch for this) is a great idea. But here's another trick, wait until the soil is bone dry. Nothing worse than a rusty nail in sopping wet soil, nail patches that are virtually undetectable in the spring when the soil is sopping wet are much more detectable in late summer after the soil dries out. You will lose a bit of depth due to the dry soil but nails get small in dry soil. One other tip from the late great Dave Z (RIP Dave) if you are convinced there are good targets begin digging the nails out of the way. A rusty nail can pollute quite a large area of ground. After digging the nails you may have to let the soil rest for a season, Explorers hate disturbed soil, but it sounds like your nails are shallow so may not be as much of an issue. Another strategy is to detect the area from multiple angles, having hunted many nail patches in NY many of my silver spills and big silver finds were masked by iron such that I could only get a signal from 1 angle, say 12 o-clock. From 9, 6, 3 o-clock nothing but iron with no hint of a coin. Mind you from 12 o-clock it was a textbook silver ID on the screen. Don't let a nail falsing talk you into digging, the rusty nail bounce pattern (top left corner to right edge of screen, cursor half off the right edge, down about 3/8 inch from the top is nearly foolproof 99% rusty nail falsing. The only other thing that will hit in that area is a silver half/dollar and a target that large won't be bouncing left/right in the rusty nail bounce pattern. Quarters, large cents will ID higher along the right edge. Finally, the rusty nail target there's no defense for, a bent nail. The quality of the tone will be crappy compared to a large silver coin but that it will false right edge and not bounce to the top/left corner much...I can't not dig those. lol
Interesting how some nails, like nails bent into an 'S' shape sound pretty goood in the ground but once they are above ground they come in definately as iron. Must be the halow effect in ground?