NorthStar 972, Быстрый старт и справочное руководство

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Reference section 7 — Echo sounding
Viewing past echoes using SoundTrac Northstar 972
Press this key again to cycle through the
available sizes: small, medium, large, and
huge.
Press the cursor pad up and down to set
the position of the box along the left edge
of the screen.
Press the cursor pad up and down to set
the position of the box along the left edge
of the screen.
Viewing past echoes using SoundTrac
On the
SoundTrac
screen, you can use
Northstar’s exclusive SoundTrac feature to
look back and examine past echo data.
To enable SoundTrac:
1. At the main Echo Sounder screen, press the
cursor pad to the left.
The position marker — a dashed vertical
line — is now displayed.
2. To move back to echoes that were displayed
within the past few minutes, continue pressing
and holding the cursor pad to the left.
The 972 recalls echoes from the last 3000
pings.
As you move the position marker with the
cursor pad, the marker speed accelerates
to quickly scroll to the desired location.
The lat/lon of the position marker is
displayed at the bottom of the picture,
along with the time elapsed since the ping,
and the distance and bearing from your
present position to the marker (assuming
the navigator is providing position data).
As you move the position marker left and
right, these coordinates change
accordingly.
NOTE:
When you use the position marker on a split
screen (showing either two frequencies, or
zoom mode), each half of the screen has a
position marker. Both markers designate the
same physical location.
The number of minutes of past echo data
available depends on two factors:
•
the depth of the water
•
the advance speed
In deeper water, the sounder pings at a
slower rate, so the echo sounder saves data
over a longer period of time. A slower
advance speed will have the same effect.
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