1 Fishfinder 160C Owner’s ManualoPerAtIng InstructIons > the setuP MenuBackgroundUse this setting to change the Backgroundcolor. The available settings are: black,blue, and White.NumbersKeel OffsetUse the Keel Offset setting to offset the surfacereading for the depth of a keel. This makes itpossible to measure depth from the bottom of yourkeel instead of from the transducer’s location.Enter a positive number to offset for a keel. Youcan enter a negative number to compensate for alarge vessel that may draw several feet of water.SizeDetermines the size of the depth, battery,temperature, speed, and distance numbers shownon the screen, either Small or large (default).BatteryChoose to either hide (default) or Show thecurrent battery voltage.Water TempWater Temperature automaticallyappears when set to Auto (default),or you can choose to hide the WaterTemperature.SpeedSpeed automatically appears when set to Auto(default), or you can choose to hide the Speed.DistanceDistance automatically appears when set toAuto, or you can choose to hide (default)the Distance.Transducer at SurfaceEnter (+) positivenumber to show depthfrom the bottom of keel.Transducer at Bottomof KeelEnter (-) negative number toshow depth from the surface.