I have two Tracker II detectors, and an older model 2D-707. Basically, the T2 is a good machine with limited depth. I've found a merc dime at 6" and some larger coins at 8" or so. I've found aluminum can tops at 10", as well as a couple medallions between 8" and 10". I have found
a lot of jewelry in parks, especially around sporting fields (check out the "finds" album in my Photo Gallery).
Anyway, here's a synopsis about the Tracker II.
MODE:
1. ALL METAL setting goes deepest but it picks up everything and every signal is the same.
2. TONE will differentiate between silver, brass, steel, copper, aluminum, quarters, dimes (high, clear beep) and gold, nickles, iron, aluminum foil, pull tabs (low ugly tone, like you just answered a question wrong on a quiz show......

). Some targets have a mixed signal, depending on what they are made of. Like a piece of jewelry with silver and gold both on it will make a mixed signal, as will some pull tabs and other junk. Pennies, depending on their year (differing composition), can make either sound, or a mixed signal, which is
very annoying, because you'll probably dig a lot of them.
3. DISC will pretty much filter out the low tone metals, so you'll find clad and silver (and aluminum cans) but probably not gold.
GROUND:
Self-explanatory. The type of ground you're searching would determine the setting. The farther to the right you set the knob the deeper it probes.
SENSITIVITY:
This has to do with interference, although there's not much problem with that in my experience, except on wet sand.
DISCRIMINATION: Adjust the discrimination up to filter out whatever you don't want to dig, but remember, a gold ring can sound just the same as a ball of aluminum foil or piece of iron. The experts will tell you to dig most everything if you want to find the most good stuff.
It's best to use some items like a small gold ring, small silver ring, coins and pull tabs and practice with the machine to familiarize yourself with the different tones. You will learn to hear subtle differences in the signal and often be able to ignore something that's junk...... BUT, it's not an exact science, so there's always a possibility that mixed signal you ignored is something valuable.
BTW, an 'air test' will not pick up a target from the same distance as it will if the target is underground. I found this a little odd, but it has been the case for me that targets beneath the surface are detectable from farther away than those laid on top.
Anyway, my first recommendation is
get a pinpointer!! It makes locating targets
a lot faster, and saves valuable detecting time. There are many pinpointer discussion threads here, but don't be brow-beaten into buying something really expensive. There's a lot of rabid brand loyalty here at TNet and some will have a fit about 'you get what you pay for'. Read the testimonials and make up your own mind about how much you want to spend.
I have a pinpointer for each detector, a Wizard Vib-Probe ($37), a Tiny Tech Deluxe ($44) and a Bounty Hunter (came free with a BH 505 detector I bought my Dad, but they cost about $40). They all work fine, my preference being the Vib-Probe, while my Dad preferes the Tiny Tech. If you're careful and thorough in your research, you can get
more than you 'pay for'. The classifieds here at TNet are a great resource, as is the Internet itself, through Craigslist, eBay and the like. You can even check Pawn Shops.
For instance, none of my detectors cost over $50 and were all essentially brand new.
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