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 MIL-HDBK-1012/1
a) Guy insulators. Types, ratings, numbers, and spacing of guy
insulators are specified in the BESEP or set forth by the command responsible
for the design of the antenna.
b) Base insulators. Types and ratings of base insulators are
specified in the BESEP or set forth by the command responsible for the design
of the antenna.
9.3.3.3
Ladders and Platforms. For essential details pertaining to
ladders, lubber-loops, safety cages, platforms, railings, safety chains, and
similar appurtenances, refer to MIL-HDBK-1001/2. Ladders, ladder bars, or
step bolts shall be placed on pole supports or along one leg of tower framing,
except where electronic considerations prohibit use of metal in or near
supports. Where feasible, rest platforms shall be provided on towers,
preferably at intervals not exceeding 100 feet (30.5 m).
9.3.3.4
Fencing. For details, refer to Section 6 of this handbook.
9.3.3.5
Lighting and Marking. Lighting and marking of antennas and antenna
supports shall conform to FAA Advisory Circular AC 70/7460, Obstruction
Marking and Lighting. For further information, refer to Section 7 of this
handbook.
9.3.3.6
Antenna Pads. Consideration should be given to placing paved pads
at the bases of large antennas.
9.3.3.7
Lightning Protection. Lightning protection shall be provided in
the form of grounding, surge suppressor and/or sparkgaps. The working voltage
and limitations for setting the spark gap will be provided by the user
command.
9.3.4
Power Requirements
9.3.4.1
Exterior Power. Some antennas require power for operation of de-
icing equipment, rotation devices, and obstruction lights.
9.3.4.2
Cabling. Exterior power cables shall be run underground to the
antenna via cable trenches.
9.4
Helix House. The helix house normally supports an LF antenna; it
is a copper-lined building which houses the antenna tuning and loading coils
and other components used to match the output impedance of the transmitter to
the antenna impedance. The transmitter termination and the antenna
termination are also located in the helix house. The transmission system
between the transmitter and the helix house depends on the location and number
of antenna feeds and/or down-leads required.
9.4.1
Siting.
The helix house is usually located at the base of the
9.4.2
Components. The matching components generally consist of the
helix, variometer (variable inductor), and shunt variometer, but some sites
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