Garmin GPSMAP 8000 Manuale Utente

Appearance: Configures the appearance of the sonar screen 

).

Alarms: Sets sonar alarms (

Advanced: Configures various sonar display and data source 

Installation: Configures the transducer (

From a sonar view, select Menu > Sonar Menu > Sonar Setup 

> Noise Reject.
Interference: Adjusts the sensitivity to reduce the effects of 

interference from nearby sources of noise.
The lowest interference setting that achieves the desired 

improvement should be used to remove interference from the 

screen. Correcting installation issues that cause noise is the 

best way to eliminate interference.

Color Limit: Hides part of the color palette to help eliminate 

fields of weak clutter.
By setting the color limit to the color of the undesired returns, 

you can eliminate the display of undesired returns on the 

screen.

Smoothing: Removes noise that is not part of a normal sonar 

return, and adjusts the appearance of returns, such as the 

bottom.
When smoothing is set to high, more of the low-level noise 

remains than when using the interference control, but the 

noise is more subdued because of averaging. Smoothing 

can remove speckle from the bottom. Smoothing and 

interference work well together to eliminate low-level noise. 

You can adjust the interference and smoothing settings 

incrementally to remove undesirable noise from the display.

Surface Noise: Hides surface noise to help reduce clutter. 

Wider beam widths (lower frequencies) can show more 

targets, but can generate more surface noise.

TVG: Adjusts the time varying gain, which can reduce noise.

This control is best used for situations when you want to 

control and suppress clutter or noise near the water surface. 

It also allows for the display of targets near the surface that 

are otherwise hidden or masked by surface noise.

From a sonar view, select Menu > Sonar Menu > Sonar Setup 

> Appearance.
Color: Sets the color scheme and color gain.
Overlay Data: Sets the data shown on the sonar screen.
A-Scope: Displays a vertical flasher along the right side of the 

screen that shows instantaneously the range to targets along 

a scale.

Depth Line: Shows a quick-reference depth line.
Edge: Highlights the strongest signal from the bottom to help 

define the hardness or softness of the signal.

Pic. Advance: Allows the sonar picture to advance faster by 

drawing more than one column of data on the screen for 

each column of sounder data received. This is especially 

helpful when you are using the sounder in deep water, 

because the sonar signal takes longer to travel to the water 

bottom and back to the transducer.
The 1/1 setting draws one column of information on the 

screen per sounder return. The 2/1 setting draws two 

columns of information on the screen per sounder return, 

and so on for the 4/1 and 8/1 settings.

Range Lines: Shows the vertical lines indicating the distance to 

the right and left of the boat. Available for SideVü sonar view.

NOTE: Some settings require external accessories.
Select Settings > Alarms > Sonar.
Shallow Water: Sets an alarm to sound when the depth is less 

than the specified value.

Deep Water: Sets an alarm to sound when the depth is greater 

than the specified value.

Water Temp.: Sets an alarm to sound when the transducer 

reports a temperature that is 2°F (1.1°C) above or below the 

specified temperature.

Contour: Sets an alarm to sound when the transducer detects a 

suspended target within the specified depth from the surface 

of the water and from the bottom.

Fish Alarm: Sets an alarm to sound when the transducer 

detects a suspended target within the specified depth range 

and the specified color range.

From a sonar view, select Menu > Sonar Menu > Sonar Setup 

> Advanced.
Transmit: Stops the transducer from transmitting.
Shift: Allows you to set the depth range on which the sonar is 

focused. This allows you to zoom in a higher resolution in the 

focused depth.
When using shift, bottom tracking may not work effectively, 

because the sonar looks for data within the depth range of 

the focused area, which may not include the bottom. Using 

shift also can impact the scroll speed, because data outside 

the depth range of the focused area is not processed, which 

reduces the time required to receive and display the data. 

You can zoom in to the focused area, which enables you to 

evaluate target returns more closely at a higher resolution 

than just zooming alone.

Echo Stretch: Adjusts the size of the echoes on the screen to 

make it easier to see separate returns on the screen.
When targets are difficult to see, echo stretch makes the 

target returns more pronounced and easier to see on the 

screen. If the echo stretch value is too high, the targets blend 

together, and if the value is too low, the targets might be 

small and difficult to see.
You can use echo stretch and filter width together to obtain 

the preferable resolution and noise reduction. With echo 

stretch and filter width set to low, the display has the highest 

resolution, but is the most susceptible to noise. With echo 

stretch set to high and filter width set to low, the display has 

a lower resolution, but has wider targets. With echo stretch 

and filter width set to high, the display has the lowest 

resolution, but is the least susceptible to noise. It is not 

recommended to set echo stretch to low and filter width to 

high.

Bottom Track: Sets the frequency used for determining depth.

The bottom tracking control allows you to select the specific 

channel that is used to track the bottom. For example, you 

can set the bottom tracking for the low frequency for deep 

water operation.

Temp. Source: Sets the channel for the water temperature log 

when more than one water-temperature sensor or 

temperature-capable transducer is connected.

From a sonar view, select Menu > Sonar Menu > Sonar Setup 

> Installation.
Transmit Rate: Sets the length of time between sonar pings. 

Increasing the transmit rate increases the scroll speed, but it 

may also increase self-interference.

Sonar

15