went back to the old park again today to play with TTF some more. This time I opened up the screen all the way. The V nickel was the first oldie that I pulled out. The merc was second and it was a tough one. Kept getting the iron grunt and then a good tone, but the good tone kept hitting around 20-22. I had a 46 show a couple times, but then it would go 20-22 again and was shallow. well I dug a deep plug and there was the egde of silver. I rechecked my plug and got the good signal again and found a piece of aluninum and a small nail. That explains all the weird signals. The merc was getting masked. a little bit latter out comes the shield. The ground was not bad for digging. some places a little frost, but managable. Good day even if it was only 28 degrees. Hope to get a couple more days in this week. 