Sonar Zoom And Full Screen Zoom Displays - NorthStar Multi-Function Unit M121 Installation And Operation Manual

10-1-1 Extended history mode
To review an old sonar echo, use
move back and forward through the sonar
history. The time since the echoes shown on
the screen were recorded is displayed at the
bottom of the screen. Press
the most recent echo.
The digital depth shown is always the current
depth, even in extended history mode.
The History Position Bar indicates the age of
the most resent echo on the screen, and the
position of the current screen in the recorded
history.

10-2 Sonar Zoom and Full Screen Zoom displays

B
D
A Divider line
B Depth line marks the centre of the zoomed
area
C Zoom bar
D Zoom section
E Sonar history
and to
to return to
ESC
A
C
E
Northstar M121/M84 Installation and Operation Manual
History position bar
These windows show a zoomed section of the
sonar history. The Sonar Zoom display shows
the sonar history on the right and the zoomed
section on the left. The Full Screen Zoom
display shows the zoomed section only.
The zoom bar on the far right shows the area
of the history that is magnified in the zoom
section:
• Press or to adjust the zoom range
(the range of depths included in the zoom
section).
• If Bottom lock is on, the zoom depth
(the depth of the zoom section) is adjusted
automatically so that the bottom is always
displayed in the zoom section.
If Bottom lock is off, press
manually adjust the zoom depth. If bottom
lock is on it will turn off.
Bottom lock
To turn Bottom lock on or off:
1 Press and select Bottom lock.
MENU
2 Select On or Off. Or if Bottom lock is
on, pressing or
or to
will turn it off.
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