Furuno FCV 587

[charhack]

I have a problem with my FCV 587- its not reading the bottom depth correctly when moving we could be in 7' of water and the reading will be 300' but when we stop it reads correctly. What could be the problem

 

[Snips]

Charhack,
It is most likely a turbulence issue. Please post two screen shots, one using showing both frequencies going slow and another one going 15 MPH. Also have the FCV-587 in a manual range mode. By looking at your screen shots we will be able to tell you if it a water flow or not.

Snips

 

[fishhawaii]

Snips,
I have somewhat the same problem and need assistance.
I have a FCV-587 and a TM260 on a 21 Seaswirl. I love both when stopped but as soon as I speed up past 2 knots my screen turns red. I have adjusted the transducer but still can't get rid of the turbulence. Very close to center, no strakes, etc. Also beginning to wonder if some might be electrical interference.
Unfortunately I use both to see fish near the bottom in 600-1000 ft and it works great when slow or stopped. Any suggestions? Should I consider putting the TM260 on a pole? I have been considering thru hull but hardly makes sense to have a fairing as big as the boat.
Thanks,