26
Maintenance
8 Maintenance
Precautions
WARNING
Maintenance should be performed only by personnel experienced
in RF systems and familiar with this equipment.
WARNING
The broadcast industry has recently recognized the potential med-
ical hazards of intense radio frequency radiation. Don't expose
personnel to personal harm. For reference, see CFR 29, Section
1910.97, the OSHA standard for exposure to non-ionizing radia-
tion. Whenever a rigger is on the tower in the area of the
antenna, shut off the transmitter and lock it off so that it cannot
be turned on accidentally.
CAUTION
When you have had the system open for repair, you must purge it
again as described in
Purging the System
on page 16. Never
begin operating the system under power until you are sure all the
moisture has been purged from it. You can do permanent damage
to the entire system, including the transmitter.
CAUTION
When removing or replacing radiators on the tower, never let the
weight of the radiator hang on the cable. This will damage the
connector and possibly the inner conductor. Support the weight of
the radiator until the mount bolts are tightened.
CAUTION
Do not use silicone grease on an O-ring, as this will soften the sil-
icone O-ring. Use only a light lubricating coat of petroleum jelly
(provided); too much may hamper electrical contact and contami-
nate the interior of the system.
Be sure the O-ring is properly seated in its groove and not
pinched between the flange contact surfaces.
Maintenance Log
Shively recommends that you keep a maintenance log; in it record per-
formance parameters such as readings of VSWR.
Such a log can be invaluable in spotting and identifying problems.
Sam-
ple Maintenance Log
on page 28 shows a suggested log form you may
use if you like.
Physical Inspection
The antenna system should operate for years with no problem. How-
ever, any time you have a rigger up on the tower, it's a good idea to
have him check for general condition, looseness of components, and
electrical damage. During this inspection, all mounting, flange-connec-
tion, and electrical hardware should be tightened.
Summary of Contents for 6017
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