Kongsberg Seatex AIS 100, Instruction Manual

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Seatex AIS 100 Instruction Manual, rev. 5 Installation
45
GPS antenna offset arms
Position data for the GPS antenna needs to be input to the AIS as a
part of the configuration settings. The figure below shows the offset
arms to be configured.
Figure 21 GPS antenna offset arms
GPS antenna cabling
•
To achieve optimum performance, the gain of the antenna pre-
amplifier should match the cable attenuation. The resulting
installation gain (pre-amplifier gain – cable attenuation) should be
within 0 to 10 dB.
•
The coaxial cable between the antenna and the AIS mobile station
should be routed directly in order to reduce electromagnetic
interference effects.
GPS antenna cable lengths
The GPS antenna cable should have a total attenuation of less than 10
dB as higher attenuation may degrade the quality and accuracy of the
position data.
Cable type Max. length
RG214 30 metres
Low loss ½" Superflex 100 metres
Applying power
After the mechanical and electrical installation is completed the
coaxial cables should be checked for short circuit between centre
conductor and shield (ground) with the antenna disconnected. If not
short-circuited, power could be applied to the mobile station.
A
B
C D