Garmin Fishfinder 100 Owner's Manual page 19

At the top left of the display you will find the Adjustment Bar and a
variety of user-selectable information including Depth, Battery Voltage, Water
Temperature, and Speed Over Water. To provide data on Water Temperature
and Speed Over Water, the Fishfinder 100 requires a transducer capable of
producing the particular data.
The Depth Scale and the Flasher Function are displayed from top to
bottom along the right side of the display. Messages and Alarm Icons are
displayed along the bottom.
The Fishfinder 100 has three levels of display backlighting, Off, Low
and High. The backlight is activated by momentarily pressing the Power
key. To change the backlight level, press the Power key repeatedly.
If the unit is unable to track the bottom for any reason, the digits in the
depth window will flash on and off to alert the user that the unit is not
tracking the bottom.
Unit Operation
Describing The Display
Adjustment Bar
Depth
Battery Voltage
Water Temperature
Speed Over Water
Depth Scale
Flasher
Alarm/Message Icons
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