Chapter 2: Installing the system
16
Placing the antenna
Mast length and diameter
The placement of the antenna must ensure a rigid structural connection to the
hull or structure of the ship. Parts of the ship with heavy resonant vibrations
are not suitable places for the antenna.
A small platform or short mast shall provide rigid support for the antenna
fastening bolts and a rigid interface to the ship.
If it is necessary to use a tall mast, use the table on page 18 to obtain the
maximum free length of the mast. Note that these values depend on rigid
antenna-ship interfaces. The cross-sectional properties and the corresponding
maximum free length give a natural frequency above 30 Hz.
It is recommended to shorten the mast length as much as possible to obtain
higher frequencies. Alternatively, mount stays or wires to stabilize the mast
further.
Fr
ee mast leng
th
(m)
OD (mm)
Summary of Contents for FB250
Page 13: ...Table of contents xii ...
Page 77: ...Chapter 3 Connecting power 64 Connecting power ...
Page 105: ...Chapter 5 Starting up the system 92 Operating the system ...
Page 129: ...Chapter 6 Service and repair 116 Replacing modules in 34 3052B antenna ...
Page 139: ...Chapter 7 Troubleshooting 126 Logging of events ...
Page 165: ...Appendix B Technical specifications 152 TracPhone terminal ...
Page 197: ...Glossary 184 ...