Well got the replacement F75 today, KellyCo replaced the whole unit so I ran out to give it a try. The farm I tried it out has been pound to death, not many coins come up but I managed to pull a few. I was able to run with the SEN about 90 in A/M's now It definitely was totally different then the other there's so much trash near the house it was very hard to detect but I keyed in a few coins, well couldn't take the machine gun hit for very long so I figured let me go into the field which hasn't been plowed in ages. the A/M dropped down to a nice steady almost quite threshold at -2, didn't get any high number out there but I was mainly concerned with it's operation. I like how the +and - hot rock sound of, it makes them is to pass by and the reading is usually 99 with no confidence reading like the manual says a bong or zip, it was right there. Well it was getting late so I went back to the house area and switched to Disc. Mode was able to run Sen. about 90, Disc all the way to tabs and notched nickel BP mode this is with the 11 DD coil which I couldn't do with the other unit GB was about 63. She was noisy but again super trashy. She pulled a few nickels out and 1 clad dime, It was 7:00 by now so I started back to the car and got a real strong hit reading dime with full CONF. reading, P/Ped it and it showed 9". Figured another bummer but thought I could use one of those "BIRDBATHS" Roland got, well at 9" Garrett PP said it was in the pile It was a NEW JERSEY Colonial Copper, it's the second one I got but pretty corroded, I could ID cause it has a Shield on the back and and a horse head and plow on the front, used soap & water and a soft brush to clean it up a little the shield shows up. They only made them between 1786-1788, so that was a real good find for the fist time out. I got to figure out how to quite it down in super trashy areas for my ears sake. Drop the SEN should help.