I bought a Tracker 1-D/505 at a garage sale last summer, used it a little just to make sure it worked, but not a lot. I took it along yesterday and found a pocketful of clad within an hour, nothing great, but for the first time in my metal detecting career, I understood the discriminator, I knew when I was over a coin. Did I pass a lot of good stuff, I'm sure of it! I'm going back next Saturday and spend another couple of hours at that spot. I'll be using that machine a lot in the future.