Lowrance X87 Operation Instructions Manual page 37

Main Menu.
Main Menu Commands
There are four "basic" Main Menu commands that you'll really want to
read more about. They are:
• Screen command: changes the contrast or brightness of the display
screen. Use this command to adjust how the screen looks under various
lighting conditions.
• Sounds command: enables or disables the sounds for key strokes and
alarms, controls the volume and sets the alarm style. If you don't like to
hear a beep each time you press a key, you can turn this off, or select
tunes or sound effects instead. The sounds are especially useful when
used with the Fish I.D. fish symbol feature and fish alarm feature.
• Sonar Alarms command: turns alarms on or off and changes alarm
thresholds. The fish alarm, used with Fish I.D., is the most popular
use. It tells you when the sonar sees a fish. You can also set deep or
shallow depth alarms and zone alarms.
• Popup Help command: turns the pop-up help boxes on or off. When
you select a menu command, these information boxes appear to tell you
what the command does or how to use the command. The default set-
ting is on, which is really handy while you're learning.
The remaining Main Menu commands are for more advanced functions,
mostly setting various sonar options. (They're all detailed in Sec. 4.)
• Units of Measure command: selects the units of measure used for
showing speed/distance, depth and temperature.
• Set Keel Offset command: calibrates the unit to show depth under
the keel or actual depth from the surface.
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