Rain Bird The Freedom System for Maxicom, Instruction Manual

Page: 14 / 46

8
Installing the central base antenna
and surge arrestor
Select a suitable site for installing the antenna that will be both
safe and give it the best performance. Most antennas are
supported by a pipe mast that is attached to the side wall, roof,
chimney, or eaves of a building with brackets, straps, or a tripod-
type mount. Antennas can also be attached to self-supporting
towers or masts and may require guying for stability.
Install the antenna directly above your equipment, if possible, so
that the antenna coaxial cable can drop straight down and enter
the building near the equipment (see fig. 6). Generally, the higher
the antenna is above ground, the better it performs. A good prac-
tice is to install the antenna about 5 to 10 feet above the roof
line, away from power lines and other obstructions. The FCC
limits your antenna to a maximum height of 20 feet above the
ground.
Make sure the site has proper clearance of any power lines, trees,
wires, or other obstructions. Measure the overall height of the
antenna:
height of the mast + height of the antenna x 2 = minimum
To install the central base antenna:
1.
Remove the antenna from the box and assemble it
according the directions included.
2.
Connect one 25-feet length of coaxial cable from the
central base antenna to the antenna connection of a coaxial
cable surge arrestor.
Caution: Do not cut the coaxial cable. Lay out the excess cable in as
straight of a line as possible. Do not coil the cable; this will add resis-
tance to data transmission and reception.
Before placing the antenna whip into the proper whip adapter, be
sure to cut the whip antenna to the proper length which depends on
your licensed frequency. See the chart included with the antenna.
Also be sure to center the U-bolt bracket between two adjacent
ground plane rods (or radials).
3.
Secure a 1 1/4-inch diameter antenna mast, which should
be at least five-feet long, to the building location you have
selected. Use the proper mounting brackets or other equip-
ment required.
4.
Attach one end of one of the RG-8/U coaxial cables to the
“pigtail” coaxial cable at the antenna. Before you mount
the antenna to the antenna mast, refer to fig. 4 for proper
waterproofing of this connection.
2
7
3
12
14
9
10
11
8
4
5
6
Height of mast
+
Height of antenna (x 2)
Minimum recommended clearance
Figure 3: Central base antenna
(Installation detail)
13
See fig. 6
for an
expanded
view of
installing
the surge
arrestor.