5
Antenna Installation
Figure 3. Flange bolt tightening
sequence
j. Clamp the mounting saddle to the feedline, using a clamp.
CAUTION
Feedstrap orientation is critical to performance. In general, the feed-
straps in a full-wave-spaced antenna will all be oriented the same, while
those in a half-wave-spaced antenna will alternate.
Install each radiator
in accordance with its stenciled bay numbers and its "up-arrow" sticker.
k. Determine what, if any, icing protection your antenna has.
• If you antenna has de-icers, go to
Chapter 3
.
• If your antenna has radomes, continue.
Installation of radomes
(if applicable)
If your system includes radomes, you can most easily install them on the
ground at this time. See
Figure 4
on page 6.
a. Each radome is shipped partially assembled on its own pallet. Disassemble
the radome halves and the radome mount.
b. Identify the top (wide mating flange) and bottom (narrow mating flange and
drain holes) radome halves.
NOTE
The feedline comes with a 20-inch-long extension in place (see
Figure
2
). This extension, in effect, moves the feedline joints outside the
radome, and thus allows you to mount the radome on the ground. You
should treat the feedline with its extension as a single unit.
c. Remove the closure plate bolts where the mount will slip under the closure
plate. Loosen the other closure plate bolts and leave the closure plates in
place on the radome.
d. Place four clamps loosely around the feedline, two above and two below the
baymount flange. Mounting the saddle is easier if the clamps are in place
first.
e. Locate the mount on the feedline as shown, centered exactly opposite the
baymount flange (use a ruler or a level to center it). The uppermost part of
the mount should be one inch from the flange of the feedline extension.
Table 1. Torque Specifications, Flange Bolts
Transmission Line
Size
Bolt Size
Torque
1-5/8"
5/16-18
12 ft-lb
16 N-m
2-1/8"
3/8-16
21 ft-lb
28 N-m
3-1/8"
3/8-16
21 ft-lb
28 N-m
4-1/16"
3/8-16
21 ft-lb
28 N-m
