Depth Finder problems

[guyara]

I have a Bottonline Tournament 4500 sidefinder fishfinder that's about 5 years old and when out on Coeur d 'Alene Lake this past week it started acting weird (I wish I could say it was acting 'fishy')...anyway, when ever I would turn on my electric ( I have a 101lb on my cavitation plate on the outdrive) the finder would show all kinds of fish at all depths and random at that. It didn't matter what speed or how long I had it on. Then, I'd turn off my elect. and the screen would go blank. Then when I started my outdrive, it would only measure depth up to about 35' at all speeds. Has anyone ever had this or these kind of problems? Guy

[Drewp]

Sounds like a classic example of electrical interference. I don't know how your electric is wired, but you should always wire fish finders as far away as possible from any other electical wiring on your boat.