NORTHROP GRUMMAN Sperry Marine NAVIGAT X MK 2, Assembly Instructions Manual

Page: 23 / 112

NAVIGAT X Mk 2 056341 Rev. AA
2: Operation Page 2-11
2.10.2.3 Magnetic Variation
Sets the parameters for the magnetic variation. Magnetic compass heading
data is automatically corrected according to the effective variation value.
If automatic input is active, the magnetic variation is read from NMEA sen-
tences received at the position or magnetic compass interface.
If manual input is active, the applicable value for the magnetic variation is to be
taken from the sea chart relevant to the area in question and entered manually.
Mode
Function: Selects between automatic and manual input of the magnetic varia-
tion value.
Settings: Auto
magnetic variation value is entered automatically
Manual
magnetic variation value is entered manually
Man. Value
Function: Enters the manual magnetic variation value.
Settings: 99.9° W – 99.9° E
Note
In case of manual input of the variation, check for the sea chart‘s date of issue
and apply annual changes of the magnetic variation, if necessary.
In case of automatic input of the variation, check that the correct value is re-
ceived from the respective data source, especially if the variation is calculated
automatically by a GPS system.
It is generally not recommended to rely on magnetic variation values produced
by automatic calculation in GPS systems.
The setting of the magnetic variation is not available if the system type is set to
G (Gyro only system).