NorthStar Navigation Echo Sounder NorthStar 491 - Manual (Page 41)

491 Echo Sounder Operations Manual Page 37
you can manually override these auto values for your specific
needs at any time. There are two depth settings:
• shift (how far below the surface the echo sounder picture
starts)
• range (the depth covered by the echo sounder picture
from the top of the screen to the bottom of the screen)
Setting the picture’s shift (starting depth)
The shift setting adjusts the depth of the top edge of echoes
pictured on the ECHO screen. You can “shift” the entire pic-
ture up and down to start at the surface of the water, or any
other depth you choose.
To shift the picture:
1. At the ECHO screen, press DEPTH.
2. Press SHIFT.
Shift window
The SET SHIFT window shows a picture of the current
shift settings (and range). The large white number in the
black box shows the current shift value. A sliding vertical
bar shows the portion of the water that the echo sounder
displays on the screen, based on the shift and range set-
tings.