Detecting Coins That Are Buried On-Edge

roadrunner_426

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Feb 28, 2006
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Has anyone done any testing concerning how much detection depth is lost if a coin is in the ground on-edge , versus lying flat ? I use a screwdriver both to locate and remove coins..it occurred to me that out of the thousands of coins I "popped" up last year, I can't remember a single one that appeared to be on-edge when I first hit it with the screwdriver..best as I could determine, they were all either flat, or nearly flat.." I F " it's the case that on-edge coins are nearly "invisible" to a detector, there must be a lot of coins left in areas that have been extensively hunted...no law, that I know, saying a coin has to go into the ground flat..another question is whether there's any reason to think that an on-edge coin might move to become a flat target over time...If a MD'er changed the angle of the search coil with the ground, i.e. from the parallel 180 to an acute angle, would that give the search head a better surface to detect with on-edge coins ? Any professors out there ?...RR
 
Ive been taught that level to & close to the ground was best for on edge as well. :?: Altho edge coins are sometime iffy sounding or dont bang out as well.
 
Almost all of my valuable silver coins I am finding are on edge. I am using the EXcelerator 10x12 SEF coil in hunted out parks and school yards. They sound like a faint whisper, but show as a high VDI. I am recovering them at 3-12 inches. I did notice that if they are on edge, they only sound off when the blade shape of the detection field lines up with the coin edge. If I turn the coil 90 degrees, they disappear. I also noticed that coins on edge make it extremely hard to pin point. It seems like they cause a false position sometimes.
 
I've noticed' especially on dimes, that if they are standing upright and leaning just a tiny bit, that I get a signal from only one direction and that I will loose the singal if I rotate 90* or so.
 
I've noticed' especially on dimes, that if they are standing upright and leaning just a tiny bit, that I get a signal from only one direction and that I will loose the singal if I rotate 90* or so.

What kind of coil are you using, a DD coil, or a concentric one?
 
One reason to get a large coil (there's many reason not to !) is for their ability to perform better on coins on edge.

A pendulum sweep is fatal when detecting but if you tie your sweep width and speed together and maintain a flat motion directly in front of you but allow a very tight up sweep at the end of each sweep your coil detects at an angle into the ground and picks up the angled coins.
Its very important you do this with four filter machines. If you use say an XLT and keep the coil totally flat, the motion at each end is not enough as you slow, stop, then reverse the sweep, to obtain much or any depth.
 
Thanks Brian..that's pretty much what I was thinking too, concerning the angle of the search head...RR
 
I use a 6x10 DD coil.

That's what I thought. Yes, with a DD coil, you can miss the deep on-edge coins if your approach swing is from the wrong direction. A good reason for detecting a field again, but from a different direction.

A concentric coil, if it is able to pick up an on-edge coin, will do so from any approach direction. Note that I am not saying a concentric is always better for picking on-edge coins at any depth.
 
The 1st day we took our new detectors out in the backyard, hubby buried a quarter at about 6" on edge. Neither the X70 nor the Ace 250 would see it (using the stock coils) from any angle. BUT, seeing as I knew where he buried it, I tried going over it with the Ace in pinpoint mode & it showed up very clearly. Back in regular search mode again (I think I was in all metal mode, not sure about Adam) - nothing. Strange?
 
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