Fish Finder losing bottom

[riden]

I have a Hummingbird 300 TX. Came with the boat.

I boat a river 95% of the time, strong current, sand/gravel bottom.

I consistently lose bottom with my fish finder at 20mph. It is a nuisance as the river is full of sand bars and very tricky to navigate.

Last couple of times out (very cold) I lose botton at 12-14 mph, so I never know the depth. My boat planes at 10mph.

The couple of times I have been on a lake I never lose bottom even at 30mph.

What would be my best course of action. Why am I losing bottom so easily now? Can I upgrade next year and see a difference that is worth the extra $$?

 

[JB]

Re: Fish Finder losing bottom

Very common performance for H'birds, riden. Air gets between the transducer surface and the water.

Upgrade to a Lowrance or Eagle with their "skimmer" transducer.

 

[xtraham]

Re: Fish Finder losing bottom

check your transducer mounting compaired to this manual



http://www.humminbird.com/images/PDF/hdr400gi.pdf

 

[Boatist]

Re: Fish Finder losing bottom

I agree with JB Hummingbird has had a big problem with seeing bottom at any planning speed. The Matrix unit is somewhat better. Like JB said get Lowrance or Eagle mount it right and you will have no problems.