To adjust sensitivity:
Press MENU until the SENSITIVITY ADJUSTMENT menu appears. Press UP ARROW to increase the sensitivity, DOWN ARROW to decrease it. When it's set at the desired level, press PWR to clear the menu.
The sensitivity percentage in use shows in this menu. As you change the setting, echoes scrolling onto the screen will show the effects of the change. If you reach the maximum or minimum sensitivity level, a tone sounds alerting you to the limits.
NOTE:
If you want to change the sensitivity in Manual Mode, first turn off Auto Sensitivity: press MENU until the menu appears. Press DOWN ARROW to select MANUAL, then press PWR to clear the menu.
To adjust the sensitivity, follow the same steps used for adjusting sensitivity in auto mode above.
GRAYLINE®
Grayline lets you distinguish between strong and weak echoes. It "paints" gray on targets that are stronger than a preset value. This allows you to tell the difference between a hard and soft bottom. For example, a soft, muddy or weedy bottom returns a weaker signal which is shown with a narrow or no gray line. A hard bottom returns a strong
signal which causes a wide gray line.
If you have two signals of equal size, one with gray and the other without, then the target with gray is the stronger signal. This helps distinguish weeds from trees on the bottom, or fish from structure.
Grayline is adjustable. The factory default for this unit is 72 percent. Since Grayline shows the difference between strong and weak signals, adjusting the sensitivity may also require a different Grayline level. The level chosen by the sonar unit at power on is usually adequate for most conditions. Experiment with your unit to find the Grayline setting that's best for you.
To change the Grayline level, press MENU until the GRAYLINE menu appears.
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