thanks greg, I have a friend coming to visit and he has a 798 . we are going to put his unit on my transducer and my unit on his transducer ,then we will know weather unit or transducer is problem.It has got so bad can hardly see on right side while left side is fine. It makes DI where it is hard also. Will let you guys know next week,am camping and on week end I come home and have internet. I thank you guys