maximum depth?
To get maximum depth from your detector, the discriminate level should be set as low as possible. As a target approaches the set discriminate level, its response drops off rapidly until it becomes negative or rejected. The closer the disc level signal gets to the cutoff or rejection point of the target, the smaller the signal received from the target. To get the absolute best depth from your detector if you want to reject pull-tabs, set the disc level control to the point where you get a broken signal from the tabs, rather than no signal at all. This will give you some additional signal on all of the good targets that are left.