Garmin gpsmap 292 Manuale Utente

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GPSMAP 292/298 Owner’s Manual 
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Whiteline
When the sonar sound waves are reflected back by the bottom, 
a hard bottom returns a stronger signal than a soft bottom. A 
thin whiteline indicates a softer bottom, while a thick whiteline 
indicates a harder bottom. Normally, a red line is used to show the 
point where water meets the bottom. This line follows the bottom 
contour, along with any significant objects lying on the bottom. 
The unit uses the whiteline function to make the bottom layer 
information easier to distinguish. These images show the Classic 
Black color scheme.
Whiteline Off
Whiteline On
Thick 
Whiteline: Hard 
bottom
Thermoclines
A rough definition of a thermocline is a break in water where 
the water temperature changes faster than the water above it. 
Thermoclines are shown as the weakest colors.
One of the unique features offered by Garmin is See-Thru
®
 
technology, which allows the GPSMAP 292/298 to hear both weak 
and strong signals simultaneously so as to identify fish returns 
under the toughest conditions, such as suspended in thermoclines 
or even hiding near structures. See-Thru technology allows the 
transducer to see through thermoclines and locate fish. This image 
is in the Classic Black color scheme 
Thermocline