Garmin CS 1522, Руководство пользователя

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CHAPTER 2 GETTING STARTED 36
2.4.3 Adjusting Contrast
In ClearVü and SideVü modes, you can increase the contrast to highlight smaller
fish targets or create a higher intensity display of a target. This causes a loss in the
differentiation of the high intensity returns at the bottom. You can reduce the contrast if
you want to reduce the intensity of the returns.
• Rotate the [CTRST] knob to adjust the gain and reduce noise on the screen.
• You can also adjust contrast by pressing [MENU] > Sonar Setup > Contrast (see 3.2.2 ).
2.4.4 Adjusting TVG
The intensity of sound reduces as sound propagates through water. As a result, nearby
objects in shallow water produce louder echoes than faraway objects in deeper water.
The TVG (Time Varying Gain) compensates for this propagation loss of sound by using
a lower gain level for nearby objects (immediately after the transmission of a ping), and
then ramping up the gain level over time as the ping travels into deeper water, resulting
in a more consistent level of gain throughout the depth of the water column. The TVG is
also useful for reducing the level of noise near the surface.
• Rotate the [TVG] knob to select a level of TVG .
Shallow
Deep
High Low
Depth
Gain
Shallow
Deep
High Low
Depth
Gain
Shallow
Deep
High Low
Depth
Gain
Low Medium High
• You can also adjust TVG by pressing [MENU] > Clutter > TVG .
TIP: Avoid excessive TVG , as weak echoes may not be displayed.
2.5 Interfacing with the Sonar Display
2.5.1 Accessing the Menu
Press [MENU] to open/close the menu window for mode-specific menu and system
settings (see Chapter 3 ).
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Menu
Sonar Setup
Sonar Setup
Clutter
Alarms
Frequency Chirp
10
Auto
No Zoom
83%
53ft
40
30
Off
Range
Zoom
Shift
Scroll Speed
Bottom Search Limit
Transmit
Navigation Info
Appearance
Settings
System
Preferences
Communications
My Vessel
Gain
45
35
50
53