Viewing the Temperature
Use the Temperature sub tab to view a graph of water temperature
changes over a period of time. The graph reads from right to left
so that the most recent temperature measured appears on the far
right side of the graph. The dotted lines within the graph indicate
intervals in the temperature scale and the duration of time. To view
temperature information, you must select Temp as the Transducer
type on the Setup sub tab.
NOTE: You must be receiving proper sonar data from another
device, such as a Garmin GSD 20 or GSD 21 Sounder Module,
to view temperature information.
Temperature Sub Tab
Changing the Temperature Display
The graph will adjust and show the temperatures changes according
to the Temperature Scale and Time Duration settings.
Temperature Scale—select a degree span from the list. Select Auto
to have the unit automatically determine the best range, or select a
span of 2, 4, 6, 8, or 10 degrees.
Time Duration—set how fast or slow the temperature log scrolls; a
shorter time duration means a faster temperature log scroll. Select a
duration from 1 minute to 2.5 hours.
Resetting the Temperature Graph
To reset the scale range for the temperature graph, press MENU,
highlight Reset Auto Scale, and press ENTER. This is useful
when the scale spans a large range due to extreme temperature
changes. You can reset the scale only when you select Auto for the
Temperature Scale.
To restore the temperature graph to defaults, press MENU, highlight
Restore Default, and press ENTER.
98 GPSMAP 278 Owner’s Manual
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