Alright, I am not the sharpest knife in the drawer but I do know when things don't work. My humingbird 787 does not even pick up my anchor when I drop the thing down and pull it up and down. W.T. you know the other letter. I have tried to adjust the sensitivity and all that and every now and then I can pick the thing up. I do see the bottom (I guess) and I see changes in the bottom even brush piles (I think) but I have never seen the arch of a fish. I have caught fish and let them run underneth the xdcr hoping to see something and...NADA. Anyone have a clue why I can see somethings but not fish? Should I send this unit in for check-out by a professional?

Don't laugh...I am not ashamed to ask for help.

Thanks