Using Sonar
Advanced Sonar Settings
To adjust advanced sonar settings, press MENU while viewing a sonar screen.
Range—the range of the depth scale on the right side of the screen (Auto or, to adjust manually, Up or Down).
Gain—controls the sensitivity of the sonar receiver (Auto or, to adjust manually, Up or Down). To see more detail, increase the gain. If the screen is cluttered, decrease the gain.
Frequency—selects how the frequencies appear on screen (200kHz, 50kHz, or Dual).
Zoom—zoom in to a section of the Full Screen. The zoom is off, or set to No Zoom, by default. Four options are available:
•2x Zoom—twice the magnification. Select Up, Down, or Auto to set the depth range of the magnified area.
•4x Zoom—four times the magnification. Select Up, Down, or Auto to set the depth range of the magnified area.
•Bottom Lock—locks the zoom window to the bottom. Select Up, Down, or Auto to set the depth range of the magnified area.
Depth Line—quickly reference a specific depth (On or Off). When On is selected, press up or down on the ROCKER (GPSMAP 4000 series) or touch and drag the line (GPSMAP 5000 series) to set the depth of the reference line.
A-Scope—creates a vertical flasher along the right side of the screen (On or Off).
Sonar Setup—opens the Sonar Setup screen. See page 41.
Sonar
Using