I have a Ace 350 I got in a pawn shop. Thought it was defective so sent it to Garrett. They said it was the coil and said they replaced it.I was giving one way signals and not giving repeatable ones. I got a sniper coil and it seamed to do better. the coil I have is not the one that comes stock. it is a 6.5x9 not the 8.5x11. any way my question is when searching in coins mode When I do get a repeating signal that shows 4 to 6 " and get a bell tome I dig and it is a nail or aluminum foil. My pro pointer detects it but if I run the object across my coil NOTHING. I re scan the hole and it doesn't detect anything. For such a simple machine this has given me a lot of grief. I am to the point to sell both my Ace 350 and my Whites Coinmaster and buy me a ATpro.