Grayline ® is adjustable. Since it shows the difference between strong and weak echoes, changing the level may require a different sensitivity setting.
To change the Grayline level, first press the MENU key until the Grayline menu appears. Now press the up arrow key to increase the level, the down arrow to decrease it. The percentage of Grayline now in use shows in this menu. Echoes scrolling onto the screen will also show the effects of the Grayline
change. If you reach the maximum or minimum level, a tone sounds alerting you to the limits.
The level chosen by the unit when it’s first turned on is usually adequate for most conditions. Experiment with your unit to find the Grayline setting that’s best.
FISH ID FEATURE
The Fish ID feature identifies targets that meet certain conditions as fish. The microcomputer analyses all echoes and eliminates surface clutter, thermoclines, and other undesirable signals. In most instances, remaining targets are fish. The Fish ID feature displays symbols on the screen in place of the actual fish echoes. There are three symbol sizes: small, medium, and large. These show the relative size between targets. In other words, it displays a small fish symbol when it thinks a target is a small fish, a medium fish symbol on a larger target, etc.
The microcomputer is sophisticated, but it can be fooled. It can't distin- guish between fish and other suspended objects such as turtles, sub- merged floats, air bubbles, etc. Individual tree limbs extending outwards from a group of limbs are the hardest objects
for the Fish ID feature to distinguish from fish. You may see Fish ID symbols on the screen when, in fact, there are no fish. Practice with the unit when the Fish ID feature is on and off to become more familiar with Fish ID. When the unit is first turned on, the Fish ID feature is automatically turned off. To turn it on, press the menu key until the Fish ID feature’s menu appears as shown at right, then press the up arrow key. To turn it back off, repeat the above steps, then press the down arrow key.
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