Raymarine DSM250, Owner'S Handbook Manual

Page: 82 / 122

5-22 DSM250 Digital Sounder Module
Figure 5-8: Bottom Lock Display with Split Windows
➤
To reposition the bottom lock image:
1. Use the trackpad to move the cursor to the bottom image until the
text
BL
is displayed near the cursor.
2. Press
ENTER
, a horizontal line appears, indicating the cursor is
active. Use the trackpad to move the line to the desired bottom
lock image position.
3. Press
ENTER
to reposition the bottom lock image, or
CLEAR
to
cancel the operation.
Using A-Scope
The scrolling bottom display provides a historical record of sonar
echoes. Use the A-Scope screen to show raw sonar data directly
from the transducer beam. This gives you a “real time” image of
fish and bottom structure directly below the transducer. This func-
tion is very useful in showing the strength of the echo returned
from a fish. At the lower end of the window, A-Scope also dis-
plays the patented Bottom Coverage width indication.
D6186-1
ZOOM FREQUENCY BTM.LOCK A-SCOPE
AUTO GC Z H
200kHz
10
20
30
80
80
0
20
40
60
ft
0
BL
BL