This means the unit is tracking the bottom in a zoom window, always keeping it on the display.
Press the up arrow key to decrease the zoom size, press the down arrow key to increase the zoom size.
When the unit is switched into the zoom mode, the letters “ZM” appear at the top of the screen. The zoom window size displays in the top right corner of the screen.
On the screen shown above, the zoom size has been changed to 20 feet.
To turn the zoom feature off, press the menu key until the RANGE/ZOOM menu appears. Now press the up arrow key. This switches the unit into the range mode, which turns the zoom feature off.
This unit has the following zoom ranges:
10, 20, 30, 60, 120, 240, and 480 feet
and
5, 10, 20, 30, 50, 100, and 150 meters.
Zoom - Manual Operation
To operate the zoom feature when the unit is in the manual mode, first press the menu key. Then press the down arrow key in the RANGE/ZOOM menu to place the unit in the zoom mode. The zoom size menu automatically appears next. You can change the zoom size by pressing the up or down arrows. After you select the desired zoom size, press the menu key until the “MOVE ZOOM” menu appears. This menu lets you move the zoom window up or down in one foot
increments by pressing the arrow keys. Thus, you can move the zoom window up towards the surface, down to the bottom, or anywhere in between. The window stays where you put it. It doesn’t track the bottom signal.
To turn the zoom feature off, press the menu key until the RANGE/ZOOM menu appears. Now press the up arrow key. This switches the unit into the range mode, which turns the zoom feature off.
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