Spot Soundings - VDO MAP 7w Plus GPS User Manual

Navigational information normally found in good pilot books and a presen-
tation software which displays special Port Facility Symbols.
Ports & Services
♦
Areas along shore with facilities for mooring, downloading and uploading of
ships, generally sheltered from waves and winds. Port installations are piers,
wharves, pontoons, dry docks, cranes... .
Route
♦
Sequence of Waypoints connected by segments (Route Legs). Among the avail-
able Routes, only one is the Active Route, which is shown by a straight line and
arrows to indicate the direction.
RTCM = Radio Technical Commission for Maritime Services
♦
The data format created by the Radio Technical Commission Maritime to trans-
mit Differential GPS corrections.
Scale
♦
Magnitude of the reference scale expressed in the actual unit of measure and
the current Map Datum.
SNR = Signal to Noise Ratio
♦
Ratio between the magnitude of a radio signal and the magnitude of the noise
(that is, the interferences). The SRN is expressed in decibels and it is associ-
ated to the GPS satellites signal quality.
SOG = Speed Over Ground
♦
Current velocity at which the vessel is travelling, relative to a ground location.
The SOG is normally provided by the GPS sensor.
SPD = Speed Through Water
♦
Speed of the vessel relative to the water.

Spot Soundings

♦
Depth of the water in a specific and charted position. It is represented on the
map by its own value expressed in the current depth unit.
STR = Steering
♦
Difference between COG and CTS. If COG is 25° and CTS is 30°, then STR is
5° Right.
Total Engine Hours
♦
Total operating hours of the machine. This value is not calculated in the plot-
ter, but read from the machine.
TD = Time Difference
♦
Loran positions are determined by precise timing of the intervals between
reception of pulses transmitted by pairs of stations in the selected chain. Be-
tween any two stations a ship must be located somewhere along a line of
possible positions where the measured Time Difference, TD, between arrival
of pulses from those stations would be observed. The TD is measured from
the time of reception of the master station signal to the time of reception of
the slave station signal (see also Pair).
Tide
♦
Periodic rise and fall of the surface of oceans, bays, etc., due principally to the
gravitational interactions between the Moon and Earth.
Tracks & Routes
♦
Recommended and established routes for ships at sea, including traffic sepa-
ration schemes, deep water routes.
TRN = Turning
♦
The difference between COG and BRG. If COG is 80° and BRG is 75°, TRN is 5°
Left.
TTG = Time To Go
♦
Estimated time needed to reach your destination, based on your current speed
and the distance to destination.
User Manual
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