Garmin GPSMAP 276C Owner's Manual page 100

S U S >
ETTING UP AND SING ONAR
• Btm (Bottom) Split—shows two reduced pictures, the right
at the original depth scale and the left showing sonar returns
from the bottom up. All target depths read as a distance from
the bottom.
• Btm (Bottom) Lock—shows returns from the bottom up on
the full screen.
TIP: Quickly zoom in and out of the Sonar display by pressing
the IN and OUT keys. Turn off the zoom function by pressing the
OUT key until the No Zoom setting appears.
View/Span—changes the viewing range of a zoomed display. If the
display is 2X or 4X split, only the zoomed portion on the left side of
the display is affected by the change. If the display is Bottom Split
or Bottom Lock, Span adjusts how far off the bottom the unit shows
data. This option is available when a Zoom scale other than No
Zoom is selected.
Gain—allows you to control the sensitivity of the unit's receiver,
which provides flexibility in what appears. To see more detail,
increase the receiver sensitivity by selecting a higher gain. If there is
too much detail or if the screen is cluttered, select a lower gain.
Target Level—adjusts which colors are used to show sonar
information. A Color Bar appears on the right side of the screen
as you adjust this setting. A higher percentage results in more
92
U S P
SING THE ONAR AGE
strong-signaled colors shown on the sonar display. A lower
percentage results in more weaker-signaled colors shown on the
sonar display. This setting does not increase or decrease the unit
Gain.
Whiteline—controls how the unit shows information about the
bottom type (hard or soft). With Whiteline Off, the bottom return
shows as red. Set Whiteline at Normal or 1–100% to determine
bottom hardness. See page 100
Frequency—allows you to choose a transducer frequency.
Frequency refers to the "pitch" of the sound that the transducer
sends and receives.
Depth Line—adds a horizontal depth line across the display that is
used to measure the depth of underwater objects. The depth of the
line appears in a box on the right side of the line. Press Up or Down
on the ROCKER to move the line on the sonar display.
Noise Reject—helps filter unwanted noise from the sonar display.
The Noise Reject can be turned Off, set to Normal (automatically
adjusts for optimum viewing) or to a fixed 1–100% setting. When
setting the Noise Reject, remember that a higher noise rejection
setting is less likely to show fish or structures.
for more information.
GPSMAP 276C Owner's Manual