As for me, I dig until I find the target or the reason there is a signal.
Example: I got a signal with an old S63TR i had many years ago on my farm. The target area was about 3' in dia. I finally resorted to using a post hole digger in the center of the target. I WENT DOWN 3'. As I moved the coil up and down in the hole, I noticed that at about half way down to the bottom, the signal faded. After thinking about this I dug down on the edge of the target signal ann hit the wheel rim about 8" down. Live and learn!
Example: I was walking along with my 2 Box detector and got a loud signal for about 12'. I backed up and came in at 90 degrees and picked up the signal from 6' out from a stone wall. The signal was a .50 cal. ammo box hidden in the wall. It was a geocache box.
Summary: Something is triggering your detector. Now it may be that you have your sensitive set a tad high and entered an area of higher mineralization. In that case the signal would be caused by the ground balance shifting.
: If you are digging and your signal decreases as you dig, it is on the side of the hole.
: My theory is I don't want to die like that cat. I have even gone so far as to bring out a back up detector to verify a target.
Some people can take the mystery of not knowing, but not me. I have done trouble shooting all my life, and only been skunked once. Frank, Have a good hunt.
