52 GPSMAP 5000 Series Owner’s ManualUsing SonarUSinGS onarAdvanced Sonar SettingsTo adjust advanced sonar settings, touch Menu while viewing a sonar screen.Range—adjusts the range of the depth scale on the right side of the screen. Touch Auto or touch upor Down (or drag the adjustment bar) to manually adjust the range.Gain—controls the sensitivity of the sonar receiver. Touch Auto or touch up or Down (or drag theadjustment bar) to manually adjust the gain. To see more detail, increase the gain. If the screen iscluttered, decrease the gain.Frequency—selects how the frequencies appear on screen (200kHz, 50kHz, or Dual) when using adual frequency transducer.Zoom—zooms in to a section of the Full screen. The zoom is off (No Zoom) by default. Three otheroptions are available:2x Zoom—twice the magnification. Touch up, Down, or Auto to set the depth range of themagnified area.4x Zoom—four times the magnification. Touch up, Down, or Auto to set the depth range of themagnified area.Bottom Lock—locks the zoom window to the bottom. Touch up or Down to set the depth rangeof the magnified area.Depth Line—quickly references a specific depth (on or off). When on is selected, touch and dragthe line 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 51.•••