KVH Industries TracPhone FB250 Installation Manual page 30

The tables in the next sections give some suggested design values for the free
part of the mast (shown on the previous page).
Note
The tables list the values for steel masts.
For aluminium masts, the free mast length is reduced to 75% of the
values for steel.
High masts or installations on ships with high vibration levels should be
further stabilized by stays or wires from the mast flange. Also mount vibration
isolators between the flange and the radome. For the FB250 compact dome
antenna, the vibration isolators are included in the Mast mount kit.
Note
Stays and rigid masts can still not prevent vertical vibration if the
mast is attached to a deck plate that is not rigid. Make every effort to
mount the mast on a surface that is well supported by ribs. If this is
not possible, provide extra deck plate propping.
Chapter 2: Installing the system
Placing the antenna 17