fish finder problems

[hookedupf7]

This spring I bought a used eagle fishfinder  off a buddy. I think it is a 640. It has the gps with the external antenna. I have been having problems with the sonar loosing signal while trolling with it. The depth starts blinking then the screen gets blank. Then after a while it seems to fix itself for a bit. I have played around adjusting the tranducer but it doesn't seem to help. The gps keeps working fine. When I installed it I just used a wire under the dash that my old lowrance was hooked to. That seemed to work fine. Should I run a wire all the way directly to the battery? Also about a month ago battery died out on the lake. I charged it up and load tested it and it tested alright. Any help would be appreciated!!!!!

[LongLine]

Yes, Fish finders should go direct to the battery. (with an in-line fuse)

 

Are you sure you don't have an over or under voltage situation?

 

Tom B.

(LongLine)

[Knotlost]

You have either a bad connection to the "puck" or internal corrosion that will toast the unit... 

 

I had one same way.

 

PK

[hookedupf7]

Tom I am wondering if it isn't a voltage issue like you are stating. I have a buddy that used to be a marine mechanic. This sounds like. A job for him. First I am going to run to wires to the battery for my next trip. I don't think it is anything with the finder because it worked good for him. When you say puck what do you mean by that?

[hookedupf7]

Tried the boat out tonite. It didn't seem to lose signal but now the navionics chip wasn't working. Any input on this? I think next season a new graph may be in order. Grrr.

[Sk8man]

Puck is another name for the transom mount transducer

[hookedupf7]

Fish finder seems to be working better but now my navionics chip is not working on the gps. Do they ever go bad?