Leica apMK12, Operation & Installation Manual

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24 Version 1.5
Operation & Installation Manual Navigate
The window below the wind data provides information relating to your
course and speed. You will find the
Course Over Ground (COG calcu-
lated by the MX421 smart GPS antenna), Heading (HDG, your NMEA
0183 compass input) , and Heading To Steer (HTS) data on the left side
of the window. HTS data is calculated by considering your Heading,
minus COG and adding BRG to the waypoint. In doing so, the soft-
ware considers any Set to be included in the HDG value. If there is no
Set, your HDG should be equal to COG. Set and Drift is calculated from
GPS and your Speed Log (NMEA 0183 VHW record or Pulse input)
and Compass (NMEA 0183 HDM, HDT, or VHW) input or an operator
manual input.
On the right side of the lower left window you will find the Speed Over
Ground (SOG, calculated by MX421 smart GPS antenna), Speed Log
(LOG, the NMEA 0183 or pulse speed input), and the Waypoint Clo-
sure Velocity (WCV). WCV reflects the real time velocity from your
present position and course towards the next waypoint. The VMG
and WCV are calculated from GPS data. Refer to the diagram below to
see a graphical representation between VMG and WCV.
Present
Position
SOG 13 Kn
Beginning
Waypoint
Next
Waypoint
Original Course Line
Actual
Course
Line
VMG
Towards
Waypoint
10 Kn
BRG
Effect of
Set & Drift
6297_01B.100
Present
Position
SOG 13 Kn
WCV 9 Kn
Beginning
Waypoint
Next
Waypoint
Original Course Line
BRG & RNG
Extended
Course
Line
WCV is based on
Extended Course
Line (COG), SOG,
BRG & RNG to WPT
Effect of Set & Drift
HTS to
counter
Set & Drift
Velocity Made Good:
Distance to
Waypoint Travelled
Waypoint Closure Velocity:
8/13/01, 11:30 AM 24