Hello everyone I'm still new with the fisher F70 but I'm really starting to figure it out I had it now for 2 weeks and Benn detecting pretty heavy I got a question though. Why do it jump allot even when I dig it up its a coin?? Like a few wheat Pennies I found jumped from pull tab to foil but I dug it anyway and it was a wheat penny?? Then I got a zinc and tab signal I dug it and another wheat penny?? Is there anyway I can make it get better ID's on coins? is this the nature of the F70?? Then sometimes when I'm detecting it starts chattering off so I raise the coil to see if it's electrical interference and the chattering stops then as soon as I put it to the ground it starts again so I re ground balance and it still dose it so I turn sensitivity down I raise Disc and it still gets little chattery signals there not solid there like quick cherps then go away what can I do to fix this???? Please anyone with F75 or F70 with the 11" DD coil can help me cause I'm running 11"DD coil. Please any help here I'm getting worried????