Okay, people seem to sometimes take my post in the wrong way, so let me say this first! I'm trying to help in the best way I can even if the wording comes out wrong or is taking wrong
The sound at depth will only change if the detector has modulated audio (if I remember correctly) that is when an object sounds farther away (fades) as distance is increased between the target
and the coil. Well in that case its distance and not so much what is making up that distance, water, air, or dirt is all distance! In other words you can do air test and get a good idea of the sound of
modulated audio response, the target response should fade as the distance is increased.
Now there is MANY things in the ground that changes the detector's response to good targets, and its possible to recreate some of them while its impossible to recreate all of them.
A coin tilted enough will often time give a double beep beep and do so to a point that it will have you digging two holes to find out that the target is right smack in the middle of both digs.
Next is target masking, but the problem here is every masking item is a little different based on size, alloy, above or below the target, how close it is to the good target. There is just two
many variables to try and include in a test garden and I'm not saying the idea of a test garden is a bad thing, I just don't know that its that great of a thing for much of what your intending to try and do.
To get silver coins the coins has to be there first. In many areas where metal detecting has been VERY popular for more than three or four decades the silver coins have been thinned out a LOT.
Next I look for things when I dig that hint to the age of the area and items lost, like wheat pennies, or at lest pennies dated pre 1958. I look for the old beaver tail beverage tabs. If your digging those then
your doing the right thing to find silver, especially wheat cents.
Here is another idea that may help you find some silver coins, when you first start a hunt and your still fresh dig a few more of those questionable targets and try to make a metal note of how it sounded
and what came out of the ground, now I get tired of digging so many extra items to do for the entire hunt, but I can deal with it for awhile, this is one key element to gain experience and a bond between
the operator and his/hers detector.
There is a couple of fair grounds around our area and they are several people that hunt them as soon as the tent stakes are pulled up, well it took me awhile to learn this but I started tuning in to those broken
responses, but ones that sounded more like bunches of close together good beeps and when I did that I started finding pocket spills!!!! then I started finding pockets spills that were 3" and 4" deep that had
been past over for several years. To to many detectorist a broken response from a pocket spill sounds closely the same as a junk target.
Another thing I've found over the years is a repeatable beep to many means totally different things. I've learned that often times a repeatable response in ANY single one direction is the DIG target,
it doesn't have to be a back and forth in the same direction, or a four way pass, if I can get a repeatable response in any even single swing in any direction I'll dig, so many times it'll be a coin.
You can gain the most experience by digging more questionable responses in the field, and making mental notes to what came out of the ground by what it sounded like. I've read post on forums
where the person only digs 4-Way repeatable responses! I love to go behind these people and hunt, they only get the easiest to get targets and leave so many good targets, then you have people that only dig
the 2-Way responses, they are still people I like to go behind and hunt because they still leave a lot of good finds. Don't get me wrong, I'd rather get there first but that just don't happen much these days, somebody
has hunted it before. I learned the single response method while I had my CoinStrike, I was hunting in a heavily hunting park and I was getting a lot of responses that I could only get in one single direction, the
area was old enough that I knew dated back to silver, so I started digging some of them and I was amazed at what I found out, a good bit of them were coins that were in close proximity to a single piece of trash
metal, swing in one direction (will say south) and the response dropped out, swing (north) and I a good response. And in most every case it was either a coin and junk, or at lest good piece of metal next to a piece junk.
Often times while hunting those fairgrounds I've found clad dimes and quarters mixed in with a Zinc penny pocket spill even though I had Zinc's discriminated out, because of a hint.
What I'm trying to convey is a detector in LOTS of cases will hint to a good target more than it LOCKS onto one, and to learn when its a hint and dig is when a person becomes more in tune with their equipment.
Now, back to your test garden. I would never again plant a test garden deeper than say 6" and the only purpose for that is a bit of an aid for getting use to a new detector. Once you past the 6" depth range in the field
they're is just to many variables that can change the target response that would be impossible to recreate in a test garden.
Mark
