Fishfinder not marking

[nthcbr954]

Was just wondering if anybody had any suggestions of what may be wrong with my fish finder I'm running a Raymarine c-80. it's an older unit. In May while striper fishing on the Hudson it marked a lot of fish and bait. but the river doesn't get deeper than 40 feet. Just left from an 8 Day fishing trip on Ontario and we never marked a single fish the fish finder marked bottom good. Does anybody have any suggestions on what may be wrong it's running an airmar thru Hull transducer. One that shoots through the hull. Here are some screenshots from the river..

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[hard knox]

by looking at your screen i would say that its marking plenty of fish thats what those arches are you probably have fish id switched off most guys that have been fishing for sometime just turn it off anyway . go into menu and look for fish id function and see if its shut off you dont need to be on the water to ck it in menu good luck.

[bout time]

When running Ontario or any deeper body of water make sure you are using 50hz and also it helps to change your gain from auto to manual and adjust it to see more of what you are looking for. The adjustment is in lower left corner

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Edited September 7, 2016 by bout time

[bout time]

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