14.1NAVIGATE

The Navigate Menu allows customization of the Coordinate System (Loran TD's), Map Datum, Map Orientation Resolution (angle the vessel has to change before the chart is redrawn) and Static Navigation.

 

Figure 14.1 - Navigate Menu

 

 

Coordinate System

: Selections are:

 

a. TD: Loran TD

 

b. UTM: Universal Transverse Mercator Grid

 

c. ddd mm.mmm: Degrees Minutes and Thousands of Minutes

 

d. ddd mm.mm: Degrees Minutes and Hundredths of Minutes

 

e. ddd mm.ss: Degrees Minutes and Seconds

Map Datum

: Allows selection of Map Datums. The default Datum is WGS84 as C-MAP cartography

 

has been compiled using the WGS84 Datum.

Map Orientation Resolution: Sets the angle the vessel has to change before the chart is redrawn. The default setting is 30 degrees. Example: if the vessel is heading 000T at a speed of 25 Knots, the display will redraw:

 

a. In Home mode the GPS Chart Plotter centers the location of the vessel in the center

 

of the display. To keep the vessel in the center of the display the GPS Chart Plotter

 

will occasionally redraw.

 

b. If the vessel changes course greater than 330T or more than 30T the chart will be

 

redrawn.

Static Navigation

: Sets up a threshold for the speed. When the speed received from the positioning device

 

is under that threshold, the GPS Chart Plotter displays zero.

The Loran TD selection allows the GPS Chart Plotter to be set up so the user can enter in LORAN TD’s directly into the GPS Chart Plotter. After the TD’s have been entered, and the user changes to ddd mm.sss (Degrees Minutes and Seconds) the TD’s will be converted to Lat/Lon coordinates.

To use the TD Coordinate System the user must setup the Chain and Pair information of the TD’s. If you do not know this information, refer to paper charts that show the Chain and Pair information.

ASF1/2 : Additional Secondary phase Factor (TD Coordinate System)

Correction to TD1/2 values which can be inserted by the user.

Alter : Alternate Solution (TD Coordinate System)

Parameter selected by the user that is applied in the conversion of TD values to geographical coordinates Lat/Lon. It defines which of the two possible solutions can be used.

CPV550

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