GUIDANCE MARINE Artemis Mk6, Installer'S Manual

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Installing a Mobile Station (Continued)
4. Mount the antenna with the six self-retaining M6 hexagon socket-head screws of the
antenna, using a 5 mm hexagon key.
!
Tightening the bolts if the antenna has not been properly positioned will damage the
antenna flange of the antenna unit.
Closing the Vent
To avoid water from entering the antenna unit, the vent must be closed. This is done by turning
the ventilation screw clockwise and tightening it with a 5 mm hexagon key.
Connecting the Antenna Unit
See
External Connections to an Atemis Sensor
on page 15
Aligning the Mobile Antenna
The direction of the antenna mounted on the antenna unit is defined by the position of the main
shaft of the antenna unit. Directly coupled to this main shaft is a precision shaft encoder which
measures the actual position (angle) of the main shaft. The angle measured by the encoder should
be related to a reference direction. To compute the vessel’s heading from the angle of the Mobile
antenna (the relative Mobile antenna bearing) and the azimuth as received from the Fixed Station,
the Mobile antenna must be aligned with the centre line of the vessel.
If the Mobile Station is mounted at the centre line of the vessel, the bow or the stern can be used
for alignment. The best alignment will be obtained when the reference object is far away. If the
Mobile Station is installed off the vessel’s centre line, the antenna must be aligned parallel to the
centre line. In this case a reference mark must be defined (see below).
For the alignment the optional telescope is recommended. It is assumed that the station has been
configured as a Mobile Station.
To align the Mobile antenna:
1. If available, install the telescope on top of the antenna (see below).
Mounting the optional telescope on top of the antenna
Alignment of the Mobile antenna if the station is installed off the centre line
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