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Viewing past echoes using SoundTrac
Echoes from at least the past three minutes are available, depending on the depth of the water and the advance speed you’ve set.
On the SOUNDTRAC screen, you can use Northstar’s exclusive SoundTrac feature to look back and examine past echo data. To enable SoundTrac, at the ECHO screen, press the CURSOR PAD to the left. A dashed vertical
To move back to echoes that were displayed within the past few minutes, continue pressing and holding the CURSOR PAD to the left.
As you move the position marker with the CURSOR PAD, the marker speed accelerates to quickly scroll to the desired location.
SoundTrac screen
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 posi- tion marker. Both markers designate the same physical location.
Page 52 | 491 Echo Sounder Operations Manual |