Raymarine DS400 & DS500 用户手册
Chapter 4: Menu Operation
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Color Gain
Color Gain determines how echoes of different strengths are displayed. 128
colors per palette are available, with the strongest signals displayed in colors
representing the strongest signals in the currently-selected palette. The Color
Gain control sets the lower limit (threshold) for the strongest signal and is
represented as a percentage of that strongest signal.
colors per palette are available, with the strongest signals displayed in colors
representing the strongest signals in the currently-selected palette. The Color
Gain control sets the lower limit (threshold) for the strongest signal and is
represented as a percentage of that strongest signal.
A lower Color Gain percentage means a stronger echo is required to be
displayed in the strongest signal colors. All echoes with a signal strength
above this value are displayed in darker colors. All echoes weaker than this
value are divided equally between the remaining colors.
displayed in the strongest signal colors. All echoes with a signal strength
above this value are displayed in darker colors. All echoes weaker than this
value are divided equally between the remaining colors.
Your choices are:
•
AUTOMATIC: Displays colors based on current conditions (with as many
colors as possible) while minimizing noise and clutter. As conditions
change the auto-color gain adjusts.
colors as possible) while minimizing noise and clutter. As conditions
change the auto-color gain adjusts.
•
MANUAL: Setting a low value produces a wide band for the weakest colors
but a small signal band for the other colors; setting a high value gives a
wide band for the strongest colors but a small signal band for the other col-
ors. If you select manual adjustment, you will need to re-adjust the gain as
conditions change.
but a small signal band for the other colors; setting a high value gives a
wide band for the strongest colors but a small signal band for the other col-
ors. If you select manual adjustment, you will need to re-adjust the gain as
conditions change.
The default setting is AUTOMATIC.
Time Variable Gain (TVG)
TVG (Time Variable Gain) reduces clutter by varying the gain throughout
the water column. This function is useful for reducing “noise” that can
appear. Increasing the TVG value increases the maximum depth to which
TVG is applied. Decreasing reduces the maximum depth.
the water column. This function is useful for reducing “noise” that can
appear. Increasing the TVG value increases the maximum depth to which
TVG is applied. Decreasing reduces the maximum depth.
Although you can manually set the TVG level, Raymarine recommends
letting the unit choose the proper level for you by selecting AUTOMATIC.
letting the unit choose the proper level for you by selecting AUTOMATIC.
The default setting is AUTOMATIC.
Sounder Interference Rejection (Int. Rej.)
Two or more sonar-equipped vessels operating within range of each other
can interfere with sounder operation. This usually appears as vertical streaks
on the display that do not represent actual targets.
can interfere with sounder operation. This usually appears as vertical streaks
on the display that do not represent actual targets.
This option can reduce such interference, either manually or automatically.
•
AUTOMATIC selects the best rejection level for you