CZ -- sounds like you are having some of the same experiences along the "learning curve." I will look forward to seeing your "treasures!"
Yep -- I agree, a lot of falses are up in the dime/quarter zone, but won't "lock on," as you said.
This is just an aspect of learning a machine that -- in my opinion, requires tons and tons and tons of "repetitions" in order to really figure out and master. Hunting in iron has been, for me, the most difficult aspect of detecting to master, with ANY machine, and there are simply NO shortcuts as far as I can tell. You have to dig, and dig, and dig more, listening to subtle nuances every time, in order to begin to draw conclusions as to what clues may exist as to whether something is a "nail false" versus a "coin next to a nail." It's SO easy to draw those conclusions too hastily -- because in the scheme of things, VERY FEW nails have coins adjacent to them. And so, because it's so easy (at least for me) to get frustrated by "digging nothing but nails," it's easy to want to conclude too quickly that "that's just a nail false, I've heard that same tone 10 times and it has always been just a nail every time" -- and therefore choose to pass on by without digging. Until you have dug enough "coin/nail" targets, and learn what THOSE sound like, it's hard to conclude anything about what a "coin/nail" target sounds like, if all you have dug are a bunch of "nail false" targets. In other words, coin/nail co-locations may (or may not) sound quite similar to nail falses, but until you have dug enough of BOTH, it's hard to draw solid conclusions. And I am still in that place where I've dug ALOT of nail falses, but only a few "nail/coin" targets, and so I need many more of the "latter" digs, before I can draw conclusions as to how to differentiate between the two.
Steve