Si-text trawl plot 12, User Manual, Page: 111 / 118

113 User Manual
Before a new Floppy Disk can be used, you must format it, by selecting the format disk option pro-
vided by the chartplotter. This function initializes the Floppy Disk and prepares it for storing informa-
tion. Remember that if a disk is not blank, formatting it destroys any data already on the Floppy Disk.
GPS = Global Positioning System
It is a satellite based navigation system operated by the US Department of Defense. It gives the naviga-
tor a position 24 hours a day, 365 days a year under any weather conditions.
HDG/HEAD = Heading
The horizontal direction in which a ship actually points or heads in any moment (see also COG).
HDOP = Horizontal Dilution Of Precision
It is the index for position-fixing accuracy. The smaller the HDOP value, the more accurately the
position can be fixed
Home
In Operating mode (called also Navigate mode) all operations refer to the ship's position.
Landmarks
Any prominent object such as monument, buiding, silo, tower, mast, ..., on land which can be used in
determining a location or a direction.
Latitude
The angular distance North or South of the equator measured by lines encircling the earth parallel to
the equator in degrees from 0° to 90°.
LAT/LON
Coordinate system using Latitude and Longitude coordinates to define a position on earth.
LOG
Speed of the vessel relative to the water.
Longitude
The angular distance East or West of the prime meridian (Greenwich meridian) as measured by lines
perpendicular to the parallels and coverging at the poles from 0° to 180°.
Loran
The Loran Chains are groups of transmitting stations that use timed radio pulse transmissions.
Magnetic Deviation
The angle between the Magnetic North and the Compass North.
Magnetic Variation
The angle between the magnetic and geographic meridians at any place, expressed in degrees West or
East to indicate the direction of magnetic North from true North. It changes from point to point, and
(at the same point) with time.
Mark
Reference points related to cursor position (see Par. 4.2).
Natural Features
Any topographic feature formed by the action of natural processes: coastlines, relief, glaciers, ....
Navigate
Operating mode (called also Home mode) all operations refer to the ship's position.
NMEA-0183
The NMEA-0183 Data Interface Standard was developed by the National Marine Electronics Associa-
tion of America. It is an international standard that enables equipment from many different manufac-
tures to be connected together and to share information.