:rant: VERY INTERESTING

[mwaynebennett]

I took a zinc penny, a copper penny, a clad dime a nickel and a clad quarter and tested them each to see what effect their orientation to the swinging coil would have on the target indication. I first tested each lying flat and the Elite 2200 nailed each perfectly with no falsing, swinging in all directions. I then used a small blob of modeling clay to hold each coin, one at a time, in a vertical position. HOLY COW!!!

When the coil is swung at 90 degrees to the diameter, each coin registered correctly.

Swinging parallel to the diameter, each coin registered as IRON!!!

I then placed each coin at a 45 degree angle and the Elite 2200 again nainled each correctly.

This tells me that if a coin is on edge or nearly so, it may cause the Elite 2200 to mis-read the target.

Now, when one throws in the halo effect, I have to believe that I have been passing by targets that might be of value. Bounty Hunter's instructions about targets that sound differently swinging different directions is misleading and should be eliminated from instruction manuals as far as I am concerned.

Mark

 

[GoGoGopher]

I would think that it would be rare for a coin to be on edge...It would have to be lodged up against a rock, root, or gravel...I think the natural gravitational position would be flat...

 

[Ed in SoDak]

So, would it irk you less if they only beeped when any kind of metal was below the coil and not make any ID assumption? That way they would be wrong less often.

I think detectors do an amazing job of guessing at a target's ID, given the millions of possible objects, their orientation in the ground, state of oxidation, soil composition, hunting techniques, soil moisture, moon phase and apparently also the detectorist's mood.

Most manuals I've read will state somewhere that IDs are not an exact science. Only way to know is to dig 'em all, and you still won't find 'em all.

-Ed

 

[mwaynebennett]

I think that the manuals should state that the orientation of the target in the ground can influence the indicated ID and that a "mixed" signal may be a coin on edge.

Mark

 

[salmonriverhotrock]

Not trying to be a smart ellic but it proves dig everything is not always such a bad thing to do.

 

[mwaynebennett]

Well, if we should dig everything, we don't need all the whistles and bells like discrimination and target ID. It is back to to old BFO machines.

Mark

 

[bigsquid55]

Dig everything, boys! Yesterday... I got 3 solid quarter hits (ID & Headphone tone). 1 was a quarter, 1 was a military coat button, & 1 was an eyebolt! I've also gotten copper/dime hits on shards or aluminum siding pieces. One never knows! HH

 

[Ed in SoDak]

This is copied from the latest Time Ranger manual. I'd presume other BH manuals would have the same general instructions, but I didn't bother to check. As to older manuals I don't know, but at least BH does presently acknowledge the issue in this case.

Myself I prefer ID but I will check out unusual signals. I'll start out with no disc and dial it in as I encounter trash. I hardly ever disc above iron.

No need to go back to BFO, too little depth with those, but you could mount huge coils to a BFO that were easy to design and build at home.

-Ed

"Since different metal objects can produce similar signals, and since
minerals in the soil can distort the signals, the probable target ID's
are just that-- probable. There is no way of knowing for sure what's
down there other than to dig the target up and see. Experienced
metal detector users have a rule of thumb-- "when in doubt, dig".

"Long skinny iron or steel objects such as nails usually give a double
response when scanned lengthwise, and a weaker single response
when scanned crossways. This is most noticeable in the Self-Tuning
All Metals mode (Preset Program #4). However, a coin on edge can
give a similar response, so rely on both target ID data as well as
"target feel" to distinguish between different kinds of objects."