Rob, I do use the 11" coil and it seems to be limited in actual field use over air tests. Air tests get an easy 11" on a dime. In the dirt, I've never dug a coin over 8" with the exception of one lonely toasted wheat. I do dig iffy signals, dig bouncers, low conductors, anything reading deeper than 8" for sure. Even small iron.
My 5" DD gets nearly the same depth as the 11" DD. Perhaps my machine was tuned wrong when the target phase values set. Not too big an issue with me, as I'm getting enough goodies from shallow to intermediate depths to keep me happy. I've used only the 11" and 5" inch coils and did make the mistake of getting one of those giant 12*15 SEF coils. That big thing got returned, it simply did nothing for the machine in fact it hardly saw a clad quarter at 5". I would like to try the OEM 15" DD coil but I have yet to read any user input on it from F70 users-not brand sycophants. That and after the 12*15 SEF error, I'm gun shy about it.
That puts me in the same boat as you, RonK. Fool me once, and we're done, as far as the marketing noise goes. And yes, my CZ's do go deeper, a lot deeper. I do cherish them as superior depth machines. I only claim one 14" coin, an 1807 LC in town but I also got quite a few 10-12 inch coins over the years using it.
But if you can't understand why I'm happy with the F70 and it's intermediate depth let me restate the obvious. It can pick coins out of areas those deeper older machines cannot, and it will id them very accurately. That should be obvious to any long term md'er who has seen sites where say, a ground scrape of 6-8" takes place, and suddenly there are a world of coins that those deep machines did not see previously. Target masking, target averaging, co-location and other factors all play into uncovering those deep old coins.
Since I have some park areas nearby that I'd long since cleaned out with the older rigs, the F70 and for that matter most decent DD coil design machines have proven their value in those settings. There are exceptions, machines with iron masking can miss easy finds for the F70. My first silver of the year this year, the '23 Peace dollar fell into this category. My hunt buddies were using two different machines, an ETrac and a V3. The large nail over the Peace dollar nulled out the ETrac, the V3 must have averaged it in and gave a resulting junk signal. I got a clear dime signal reading 5". Found the nail to be about an inch above the dollar with one end slanted down to the dollar.
We've traded off on finding things each other didn't see since then over the summer, but I've found my F70 beats the V3 in ID'ing at depth (user and settings dependent of course) and beats the ETrac unless you run it wide open. Something most ETrac users won't do. Though the ETrac beats me hands down in depth and (again coil and user settings dependent) target separation.
So I'd agree there's brand-loyalty hype but I know what I can do with it and so it's suited to those applications where I employ it. And that's a lot of applications. Saturday I got an Eagle button GS (EXTRA QUALITY) a '25 buff and nice old Sphinx button, most likely a souvenir from an early Egyptian exhibit in Chicago. A couple days ago I got this religious pendant 7" deep in the side of a creek bed, it read a solid 80, something most all silver jewelry does on my F70.
A few days before that I got this 1864 L IH nearly on the surface of a washed hillside in an old park, where the hard packed-base is about all that's left. At the bottom of that hill, where all the dirt has washed into, it'll take some time to clear the surface trash to get the oldest coins at the bottom. Should I take on that job, you know I'll be using my newer F70 and my older CZ5.
A couple days before that a counter-stamped 1888 IH came up from 5" in a trashy park, next to an 1897 dime. Can't find 'em like I used to, but I still find 'em. But these things all id'd easily where they should w/o regard to the site or the mess in the matrix. Not that these are all uncommon, but the F70 gives me a wide range of targeting accuracy, again, within it's limitations. Works for me. So I hunt, instead of reading reviews and wondering why there is such disparity among them. I don't defend marketing, hype or especially service and attitude of certain (or any) people in the biz.
