Garmin 2006 Manuale Proprietario

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GPSMAP 3006C/3010C Owner’s Manual 
77
U
SING
 S
ONAR
 > 
U
NDERSTANDING
 S
ONAR
Understanding the Sonar Display
One of the first things to understand about sonar is that the transducer sends a 
beam down to the bottom of the water, much like the beam of a flashlight. The 
beam starts small near your vessel and expands as it gets to the bottom.
The Sonar Page does not show a 3-D representation of the underwater 
environment. Instead, the display is in two dimensions, much like if you took a 
picture of an aquarium. Only the depth of the item in the water is shown.
The strongest sonar returns appear on your screen as the most intense solid 
color (depending on your selected color scheme; red is the default). The weakest 
returns appear as the less intense, less solid colors (blue is the default). 
The bottom of the water will always be the strongest signal, and therefore the 
most intense color. The bottom is the continuous, intensely-colored line running 
across the bottom of the screen. The GPSMAP 3006C/3010C uses the latest 
technology in interpreting bottom signals; it can see through fish, structures, and 
thermoclines (shown in the weakest colors). However, large schools of fish or 
dense structures close to the bottom can affect water depth return readings.
  NOTE: If the GPSMAP 3006C/3010C is unable to track the bottom for any 
reason, the digits in the depth window flash on and off to alert you that the unit 
is not tracking the bottom.
At the top of the screen, you might see a grouping of intense colors. This area is 
surface clutter, which can be caused by waves or any other sonar interference at 
the surface of the water. Too much surface clutter can obscure your view of fish. 
You can turn down the Gain setting to reduce this surface clutter.
Between the bottom and the surface clutter, the fish appear as arches. Actual 
fish returns might not always appear as perfect arches, due to the speed, fish 
orientation, or other conditions. You can turn on the Fish Symbols setting if you 
want to see on-screen fish in a fish shape. 
Fish Symbols Turned On
The strength of the sonar return can also help you interpret the hardness of the 
bottom of the water (the thicker the bottom line, the harder the bottom).
Hard Structure
Soft Structure