Si-tex SNS-1100 User Manual page 89

• OSGB = Ordinance Survey of Great Britain
Coordinate system describing only Great Britain charts. Generally used with GBR36 datum,
which also describes only Great Britain charts. This coordinate system cannot be used in any
other part of the world.
• Pair
The two selectable secondary stations, of a Loran-C chain, which are used to calculate the
TD (Time Difference) position of a point in the map area covered by the selected Loran-C
chain.
• Pictures & Diagrams
The MAX data format allows assigning one or more image to any cartographic object. These
Pictures are typically used to facilitate the identification of cartographic objects or places
around the map: they can be the landscape layout nearby a harbour, the shape of a bridge
or of a buoy etc. On some objects, such as bridges, the image associated can represent the
Diagram representing the shape of the objects and the various characteristics (length, height,
type of bridge etc.).
• Port Info
Port Info function is a combination of a Port Info database containing all the relevant Safety
and Navigational information normally found in good pilot books and a presentation 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 available 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
Data format created by the Radio Technical Commission Maritime to transmit Differential
GPS corrections.
• SCALE
Allows the display of Map 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 associated 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.
• Spot Sounding
Depth of the water in a specific and charted position. It is represented on the map by its own
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