NOTE:
If knowing the exact depth of water beneath the keel is less important, you can calibrate the depth indicators so that they show the actual wa- ter depth from surface to bottom. To do this, first measure the distance from the face of the transducer up to the surface (the water line on the boat). In this example, we will use 1.5 feet. This will be entered as a positive 1.5 feet, which makes the depth indicators perform as if the transducer's higher in the water than it really is.
1.Press MENUMENU↓ to SONAR SETUPENT↓ to SET KEEL OFF-
SETENT.
2.The Keel Offset dialog box appears with a plus (+) sign at the front of the box.
3.Press → to the first number, then press ↑ to change the number to 1.
4.Press → to the second number, them press ↑ to change the num- ber to 5, then press EXIT. The depth indicators now accurately show the water depth from surface to bottom.
Sensitivity & Auto Sensitivity
The sensitivity controls the ability of the unit to pick up echoes. Sensi- tivity can be adjusted, because water conditions vary greatly. A low sensitivity level (from zero to 50 percent) excludes much of the bottom information, fish signals, and other target information.
High sensitivity levels let you see this detail, but it can also clutter the screen with many undesired signals. Typically, the best sensitivity level shows a good solid bottom signal with Colorline and some surface clutter.
Automatic Sensitivity
The default sensitivity mode is automatic. The unit bases the sensitiv- ity level on water depth and conditions. When the unit is in the auto- matic mode, sensitivity is automatically adjusted to keep a solid bottom signal displayed, plus a little more power. This gives it the capability to show fish and other detail.
However, situations occur when it becomes necessary to increase or de- crease the sensitivity. This typically happens when you wish to see more detail, so an increase in sensitivity is indicated. Or, wave action and boat wakes can create enough tiny air bubbles to clutter much of the water column. In that case, a decrease in sensitivity is indicated to reduce some of the clutter.
The control bar used to adjust sensitivity up or down is the same whether the unit is in the automatic or manual mode. In automatic you
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