hey guys my f70 seems to be losing power when i first got it i was getting pull tabs at 5 to 6 inches some quarters at 8 inches last few times out seems to be only finding shallow targets so today i dug a 8 inch hole and threw qaurter in the bottom would not get any signal swithed tosl and barley got a signal been running sense around 70 threshold -3 three tone disc at 15 i did try turning the sense up to 90 did not help been using the 11 inch dd coil going to try the stock coil tommorrow see if that helps any tips thanks hh