Digger27 - Thanks for the F70 info I am considering it however I am a little afraid of EMI which I have experience a little with the AT Pro - have you experience it? Do you think the F70's depth would surpass the AT (quarter @ 9.5")? Average clad & silver coin stratum in the area where I live is approx 6 to 7 inches and the soil is mild to medium mineralized without the is iron problem that you have. CZ-3D is for the deepest silver but heavy. "THANK'S AGAIN"
EMI has been a problem for several ex F70 users, we love that because others get to pick up these horrible units that are hardly used at fire sale prices.
Basically most Fishers are overpowered out of the factory, even factory start up settings can be noisy in certain sites so if you really want to hunt quietly just turn it down.
The sense setting is not what many people think and does not work like a stereo volume knob does.
99 is full power but 75 is not 2/3rd power, 50 is not 50%power, 33 is not one third power and so on.
All those lower power levels are higher than most think, there are even vids on YouTube that show owners with F75's on a sense setting under 10 and still hitting deep targets.
Is the F70 the quietest unit on the market, not on higher power settings because it is a very sensitive high gain detector, but you don't have to hunt on really high settings if you don't want to and still get surprisingly deep.
Supposedly the new DST shielding and upgrade on the F75's makes them quiet, it would be nice if they offered it on the F70 but that will never happen till they stop selling the F75 so I just learned to deal with whatever goes on at all times
I hunt at low power levels very quietly and still can hit pretty deep, I also hunt on high or even maxed out settings and have learned to deal with any extra noise and just ignore it.
Fishers will stop and tell you they are swinging over something good no matter what is happening once you learn their language.
As far as depth in great Kansas soil I regularly dug targets at the 9-10" level, my deepest was a measured 15".
Here in my bad soil that 6-7" area is what I aim to hit also and I can do that with all 3 coils I own...The standard 10 elliptical concentric, a 5" DD and a 12"DD that comes standard on the F75.
Most hunters I know or have talked to around here don't dig much past 5" in the bad stuff, not that they can't get deeper but because of the problems most signals past that depth are super jumpy and don't make much sense.
I learned to make sense of those deeper signals and have had good luck when I dig them.
Still get fooled once in awhile and dig some iron but not often and my track record is pretty good and improving as I experiment and practice.
As far as an AT Pro never used one so I have no idea how well it would compare to the F70 or work in my soil with this many problems.