Plot Aux Screen; Setting The Geodetic System; Entering The Correction Values For Latitude And Longitude - JRC JLR-7700MKII Instruction Manual

4.4.2

PLOT AUX Screen

Pressing the AUX
4.4.2.1

Setting the Geodetic System

Confirm that the same geodetic system is used for both the chart and the
navigator to be used before starting the navigation. Use of unmatched
geodetic systems will result in wrong vessel position even at the same lati-
tude and longitude, which in turn can cause an accident.
The latitude and longitude for a given position measured with the DGPS receiver is based on WGS-84
geodetic system and can be converted into the some of another geodetic system. A total of 46 geodetic
systems are stored in the equipment, any one of them can be easily selected.
Press the
select a desired geodetic system. Note that the names of the geodetic systems will be displayed only for
the first nine systems. (The rest are only numbered. See the Attachment 2-B "List of Geodetic Systems" for
the details.) The geodetic system is factory set to WSG-84.
4.4.2.2

Entering the Correction Values for Latitude and Longitude

The most accurate method to correct the GPS information against the chart is to steer your vessel toward the
buoy shown on the chart and to read the exact difference between the two positions.
Example
Position obtained with the GPS
To correct the position obtained with the GPS in case of the example shown above, it can be corrected by
shifting the position by 0.15' to the south (S) and 0.04' to the east (E), which can be made as follows.
Press the
ENT keys.
Press the 0 , 0 , 4 , 0 , E/W , and ENT keys.
key on the PLOT screen and inputting the password can make the following settings.
CAUTION
key provided on the right hand side of the GEODETIC SYSTEM or
Buoy (real position)
key provided on the right hand side of the L/L CORR, 0 , 1 , 5 , 0 , N/S , and
E141 44.06 E141 44.10
JLR-7700 MK 2 GPS Navigator
or
N34 22.15
N34 22.00
key to
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