Hello Mike,
The only thing I didn't like about the unit was the solid inductive pick-up. I replaced it with one from a "Bounty Hunter"
metal detector. It was water proof and much more sensitive. I also found that the RCA type plug on the underside of the control box that the pick-up coil plugs into gets touchy so I removed it and hard-wired it directly to the PC board. Although when I got the pick-up from the Bounty Hunter, I had to put a BNC type of a connector on the control box because this is the type of plug that the pick-up used. If you have any question about it let me know.