One of things I did wrong when first detecting with the Z, was digging too furiously to recover a signal, it then dropped down the hole, thus out of detection depth for the flat of the coil, then further compounded this fault by using the front of the coil down the hole. One soon learns the side of the coil is the go for such. Recently to further teach me of this fault I dug a solid 1grammer out at about 9", rescanned the hole with the flat, no signal, but on getting the side of the coil down the hole I recovered a couple of sub grammers. The Zs coil is a different beast to the Monos and even the DDs of the PIs.
Tis a good idea to have the user button set to manual DB at these times. If it is a repeatable signal at first and the auto GB doesn`t take it out with side to side swinging, not pumping, odds are it is a metal target. Saying that I do believe the auto GB will take out positive signals but it is rare in the ground I detect, and of course there are clay domes, tree roots etc. But you can nearly, well almost bet a repeatable signal is a good un. Have learnt to switch to manual GB after a few slow swings to outsides of the hole to ensure the auto has it right.
