Humminbird GR16 - Manual (Page 57)

across a given distance, and is the speed measurement provided by GPS. An alternate, Speed
Through Water, is provided by a speed paddlewheel, and is the measurement of the flow past
the boat, which may vary depending on current speed and direction. Speed Over Ground is
optimal for navigation because accurate destination times can be derived from this
measurement. Humminbird® products allow for input and display of both speed
measurements.
Time To Go (TTG): Time To Go is the estimated time required to reach the destination waypoint.
TTG is calculated using the SOG and DTG. See SOG and DTG.
Track: A Track is a series of saved points that define the past path of the boat. These Track Points
are saved at regular time intervals. Tracks are a useful and quick method to see where you’ve
been, and an easy guide to follow to get you back to the starting point. Generally, all GPS units
have a limited number of Track Points that can be saved before the unit runs out of memory
and begins erasing the first track points saved. Because of this, the user can adjust the Track
Point Interval menu to increase the amount of time between when points are saved, and thus
extend the distance covered by a track. Tracks can also be permanently saved to memory, and
re-displayed at the user’s option.
Track Line (TRK): The Track Line is the desired line of travel between two waypoints, and
represents the most efficient path between the two points because it is a straight line. The TRK
is measured in degrees (i.e. 321°, where 000° is North, 090° East, 180° is South, 270° is West).
See Cross Track Error, Course Over Ground.
Trackplotter: Trackplotter describes a navigation device that shows Present Position, along
with Track, Waypoint, and Routes, but NO MAP in the background. See Chartplotter.
Trolling Grid: Trolling Grid is a Humminbird® feature that displays a precise reference grid
around a waypoint. This grid is used as a guide pattern for trolling around a specific area to
assure a more efficient and complete coverage of that area. Trolling Grid resolution be changed
by zooming in or out on the chart. The Trolling Grid can also be rotated on the display to orient
it for optimal boat course for wave and wind conditions.
UTC: UTC is an acronym for Universal Time Constant. UTC is the “standard time” used in
navigation, and is the local time in Greenwich England. (UTC is equivalent to Greenwich Mean
Time (GMT)). To display the correct Local Time in a Humminbird® GPS unit, the user must use
the Local Time Zone menu and select the time zone (i.e. EST, CST).
WAAS: WAAS is an acronym for Wide Area Augmentation System. WAAS is complementary
technology to GPS that provides enhanced accuracy through correction signals broadcast from
Federal Aviation Administration WAAS satellites stationed over the USA. These secondary
signals are automatically received by the standard Humminbird® GPS Receiver. With WAAS
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