Garmin GPSMAP 235 Sounder - Manual (Page 17)

Sounder Page
The Sounder Page lets you use the GPSMAP 235 as a fishfinder. The top of the
screen contains any of seven selectable data field options, while the middle of the
page contains a right-to-left moving sonar image of the water beneath your boat.
(Note: Items appear on the screen as they pass under your transducer. Those
objects appearing on the right side of the screen are closer to you than those on
the left.) Fish are displayed as a darkened arch or a fish symbol in three different
sizes. Thermoclines (layers of water separating warmer water from cooler water )
are shown as shades of gray.
The area of strongest sonar return (or “whiteline”) is displayed as a light gray
band. Typically, the bottom will be the primary source of the whiteline. A thin
whiteline indicates a softer bottom while a thick whiteline shows a harder bottom.
A black line is used to show the point where water meets the whiteline. This
black line will follow the bottom contour, along with any significant objects lying
on the bottom. Along the right side of the screen is an adjustable scale which
reflects the depth of the area being displayed. The status bar at the bottom of the
page displays satellite signal status, digital depth, and any triggered alarms. More
on the Sounder Page may be found on pages 24-38.
A. When adjusted correctly, the bottom is outlined
by the whiteline. To adjust the whiteline, see page
30.
B. Pause the screen by pressing the EDIT/ENTER
key at any time. To continue screen movement,
press EDIT/ENTER again. Pause the screen to
allow more time to examine the screen display
and when using the underwater waypoint fea-
ture.
7
GETTING STARTED
Sounder Page
A B
Data Field Range Mode
Fish Arch
Thermocline
Transducer Frequency
Whiteline
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