Furuno FELCOM 250 - Manual (Page 7)

1
1. HOW TO INSTALL THE UNIT
1.1 Antenna Unit
General
Interfering objects (especially metal objects like masts) near the antenna can, in the worst case,
prevent reception or transmission. Further, RF radiation from the antenna will affect the human
body. Keep these and the following guidelines in mind when selecting a mounting location for the
antenna unit.
Secure unobstructed path in all directions
The best mounting location secures an unobstructed path between the antenna unit and the sat-
ellites, from horizontal to zenith. In other words, whatever the direction the antenna unit is pointing
there are no interfering objects within the main beam (22° for FELCOM 500, 40° for FELCOM
250). While this might be feasible on some vessels, on others it is impossible due to space con-
siderations. The antenna unit should be located at least three meters away from masts having a
diameter less than 15 centimeters.
Select a location low in vibration
The maximum permissible vibration amplitude in three axis direction should be as shown in the
table below. Consult with the shipyard to determine the mounting location which meets the re-
quirements shown in the table.
Freq. Range Max. Amplitude
4 to 10 Hz
2.54 mm (max. 9.8 m/s
2
)
10 to 15 Hz
0.76 mm (max. 6.86 m/s 2 )
15 to 25 Hz
0.40 mm (max. 9.8 m/s
2
)
25 to 33 Hz
0.23 mm (max. 9.8 m/s
2
)
NOTICE
Do not apply paint, anti-corrosive sealant or contact spray
to coating or plastic parts of the equipment.
Those items contain organic solvents that can damage coating
and plastic parts, especially plastic connectors.