Garmin GPSMAP 235 Sounder - Manual (Page 75)

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TracBack Navigation (con’t.)
Once a TracBack has been turned on, the sounder will take the track log cur-
rently stored in memory and divide it into segments called ‘legs’. Up to 30 tempo-
rary waypoints (e.g. T001) will be created to mark the most significant features of
the track log in order to duplicate your exact path as closely as possible. To get the
most out of the TracBack feature, remember the following tips:
• Once turned on, a TracBack route will lead you back to the oldest stored track log
point, so it’s a good idea to clear the existing track log at the start of your current trip
before you start navigating.’
• The ‘RECORD’ option on the track log setup page must be set to ‘Fill’ or ‘Wrap’ and
there must be at least two track log points stored in memory to create a TracBack
route.
• If there are not enough available waypoints in memory to create a TracBack route, you
will be alerted with a ‘waypoint memory full’ message, and the receiver will use avail-
able waypoints to create a route with an emphasis on the track log closest to the desti-
nation.
• If the track log interval is set to the ‘Time’ option, the route may not follow your exact
path (keep the interval set to ‘resolution’ for best performance).
• If the receiver is turned off or satellite coverage is lost during your trip, the TracBack
will draw a straight line between any point where coverage was lost and where it
resumed.
• If your track log’s changes in distance and direction are too complex, 30 waypoints
may not mark your path accurately. The receiver then assigns the 30 waypoints to the
most significant points of your track, and simplifies segments with fewer changes in
direction.
• When a TracBack route is turned on, the receiver will automatically erase any tempo-
rary waypoints (e.g., ‘T001’) that are not contained in routes 1-20. If there are tempo-
rary waypoints stored in routes 1-20, the receiver will create any new temporary way-
points using the first three-digit number available.
SECTION
9
ROUTES
TracBack Navigation
A B
A. The TracBack feature uses your track log to cre-
ate a route back to where you started.
B. Once a TracBack is activated, the track log is
divided into segments using temporary way-
points, and an inverted route is activated back to
the oldest track log point in memory.
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