I know this has been discussed a bunch. My 3d (1021 series) airtests a dime at 9-10 inches max. talked with Tom D but he cant help on the depth, just calibration. Talked with fisher and not sure they can either.Hmmm whats with the 11 inches plus I hear the 1021 series is supposed to get? Waiting to hear back from fisher to see if I can send it in and at least take a look see and maybe recalibrate if nothing else..