i used this machine only about 7 times--read and reread the manual and mastering the quartto. any way i have a few questions--where exactly on the coil is the reference point to dig in pinpoint mode? i end up digging a hole the size of the 10.5 coil and still find nothing. all i ever found with this detector is nails,pull-tabs etc. even when the screen icon shows coins, rings etc. please give me some good tips as i'm about to put it on ebay. this is my third detector and i thought this one would really outshine the others. thanks.