I have a BH Tracker IV and I want to give you some sound advice. Forget your machine even has a needle. My Tracker IV will "peg" the needle on EVERY piece of metal under the coil, PERIOD. That needle is completely useless, hunt the tones. My favorite way to use it is to put the right hand toggle switch on "tone mode". If you are looking for mostly coins, I have another suggestion that will help you. Put your detector on tone mode on a non-metal table. Grab a standard nickel and wave it onder the coil. (be sure that you do not have any metal jewelry or buttons on your hand)Adjust your disc knob up until your metal detector gives you a solid low tone on the nickel. This will help discriminate out junk. Grab a dime, quarter, fifty cent piece, and listen to the tones that you get from each one. When you decide to actually go out and hunt with it, dig only the solid low, medium, and high tones. If you hear a broken tone, it generally is junk. If you are new to the hobby, try digging everything until you can tell what the detector is trying to tell you. it will take you a few months before you master what the detector is "saying" to you. The BH Tracker IV is a great detector to start out with. If you really love the hobby after using the BH and you want to upgrade, go buy a Teknetics Eurotek Pro. The ETP is around $220 and it is just as good or better than the way more expensive models. Happy Hunting with your BH!