Raymarine DSM250, Owner'S Handbook Manual

Page: 19 / 122

Chapter 1: Overview 1-9
• Zoom – enlarges all or part of the bottom graph display. You can
select x2, x4, or x6 magnification and the zoom area can be auto-
matically or manually adjusted.
You can select the Zoom or Bottom Lock image to be displayed in
place of the regular bottom graph display. Alternatively, you can
set the display window to be split vertically with the bottom graph
displayed in the right hand screen and the Zoom or Bottom Lock
image displayed in the left hand screen. See
Figure 1-5 .
If you choose dual frequency, the scrolling bottom graph is dis-
played in both frequencies, split horizontally. Zoom, Bottom
Lock, or A-Scope can be displayed with the dual frequency graph.
All of these options are available when the sonar data is displayed
in a half-screen window.
Sounder Functions
The DSM250 includes the following functions:
• Automatic or manual selection of scroll speed for bottom graph
display
• Automatic or manual selection of transducer frequency
• Automatic or manual selection of depth range limits
• Automatic or manual selection of Gain, Color Gain, and STC set-
tings
• Set up alarms for Fish, Shallow water and Deep water
• VRM marker to determine depth and distance
Operation of these functions is described in Chapter 3 and
Chapter 6 .