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Garmin 740s - Sounder Gain

Old 09-22-2018, 06:33 AM
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Default Garmin 740s - Sounder Gain

I have a 740s on a new skiff that I just bought and the gain doesn’t appear to be working correctly . The picture I took yesterday is with full gain. It also seems to increase clutter/gain below the bottom when I crank it up. There is a lot of clutter below the bottom.

I did a software update yesterday.
Sorry for the poor picture. Glare was worse that expected.

Any thoughts?
Old 09-22-2018, 08:14 AM
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Not familiar with that unit but best guess from that screenshot is white line turned up too high. Try using this to check or adjust it.
That would not be noise if I'm correct but the sounder adding white to show you the strongest returns.
76GPSMAP 700 Series Owner’s Manual Sonar Showing and Configuring the Whiteline

You can highlight the strongest signal from the bottom to help define the hardness or softness of the signal.
1. From the Home screen, select Sonar>Sonar Setup>Whiteline.
2. Complete an action:• Select High to turn on the whiteline with the most-sensitive setting. Almost all strong returns are highlighted in white.• Select Medium to turn on the whiteline with many strong returns highlighted in white.• Select Low to turn on the whiteline with the least-sensitive setting. Only the strongest returns are highlighted in white

Last edited by Grunts N Grits; 09-22-2018 at 08:20 AM.

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