NorthStar Navigation NorthStar 491 manual Viewing the seabed depth, Viewing the depth marker

Viewing the seabed depth

The seabed depth (the “bottom”) is displayed in a black box at the left edge of the ECHO screen.

You can change the size and location of the depth box on the ECHO screen. Its size on the SOUNDTRAC screen is always small.

There are four available sizes:

•small

•medium

•large

•huge

To resize the depth box or move it up or down:

1.At the ECHO screen, press DEPTH.

2.To cycle through the size choices, repeatedly press BOTTOM BOX. To move the box up and down, press the

CURSOR PAD.

3.Press RETURN to go back to the ECHO screen.

The depth box can also be adjusted by pressing MORE, then pressing DATA.

Viewing the depth marker

You can use the depth marker to accurately measure the depth of an echo. To display the depth marker—a dashed horizontal line—and move this marker up or down, press the CURSOR PAD down. Attached to the depth marker line is a small black box, which displays the marker’s exact depth.

The depth marker also affects the display in Marker Zoom mode.

Changing the depth settings

You can adjust the shallowest and deepest echoes to be shown on the ECHO screen. In automatic mode, the echo sounder sets these values based on its current environment. However,

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