TM 11-5985-335-15
g. Instruct the antenna person at station B to rotate the antenna slowly (+15 degrees off the original position) to
obtain at station B a maximum received rf input level indication. If more than one peak is observed, use the peak of
maximum amplitude.
h.
Instruct the antenna person at station B to adjust the antenna tilt angle (using the tilt rope of the tilting
assembly) for a maximum received rf input level indication.
2-8.
Operation Under Unusual Climatic Conditions
Antenna AS-1425/GRC has been designed to operate under conditions of extreme cold and hot climates. However,
additional precautionary measures are necessary to preclude inadvertent damage or degraded operation. The
precautionary measures are detailed in a, b, and c below:
a.
Subzero temperatures and climatic conditions associated with cold weather affect the operating
efficiency of equipment. Extreme cold causes cables and wires to become hard, brittle, and difficult to handle. Ice
formations and snow deposits may impede normal operation of moving parts. The following precautionary measures
apply:
(1)
Be careful when handling the waveguide sections and power cable so that kinks or unnecessary loops
will not form and result in permanent damage.
(2)
Keep protective covers on the feedhorn when the equipment is not is use.
(3)
Do not attempt to rotate the antenna when ice loading on it exceeds the prescribed limits.
(4)
Do not lay tools or parts directly on the ground; use a container or a tarpaulin.
(5)
Operate the antenna deicer equipment.
b. In warm, damp climates or swampy regions, the equipment is subject to damage from moisture and fungus.
Observe the following precautions:
(1)
Frequently check the antenna for condensed moisture and fungus growths. Thoroughly wipe moisture
from the antenna with a lint-free cloth; clean off fungus immediately.
(2) Frequently check the level of the antenna to assure that uneven settling of anchor cables has not occurred.
Be sure that anchor cables have not loosened excessively in rain-softened ground.
c. In hot, dry climates, the exposed parts of the antenna are subject to damage from blown dirt and dust. Minimize
the effects of dirt, dust, and sand by observing the following precautions:
(1)
Be sure that equipment dust covers are serviceable and are installed when the equipment is not in use.
(2)
Maintain the equipment by cleaning it frequently and immediately after dust storms.
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