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MIL-HDBK-1012/1
Section 9:
ANTENNA SYSTEMS
9.1
General. The design of antennas involves three basic
considerations: siting, arrangement and selection of types of antennas and
circuitry, and structural supports. Requirements for siting, separation and
spacing, types of antennas, circuitry, grounding systems, and propagation are
normally determined by NAVELEX. Refer to Section 1 of this manual for
information on procedures and responsibilities.
9.2
Site Consideration. For information concerning site
considerations, refer to NAVELEX 0101,103; NAVELEX 0101,104; and NAVELEX
0101,113.
9.3
Design Criteria
9.3.1
Structural. Antenna supporting structures shall conform to the
NAVFAC DM-2 Series, Structural Engineering. Special criteria, such as
deflection and twist limitations for supports, shall be as specified in the
BESEP. Wind load shall be calculated using the basic design loads from MIL-
HDBK-1012/2 with no increase in the basic allowable unit stresses. Towers 300
feet (91.44 m) or less in height may be designed in accordance with Electronic
Industries Association (EIA) Standard RS-222-C, Structural Standards for Steel
Antenna Towers and Antenna Supporting Structures; design of towers greater
than 300 feet (91.44 m) may conform to this standard when it does not conflict
with more stringent requirements in MIL-HDBK-1002/3, Steel Structures and
NAVFAC DM-7 Series, Soils and Foundations, or the BESEP.
All structural steel towers used as vertical radiators shall be
galvanized. Galvanizing should be considered for other structural steel at
locations where difficult access, height, limitations on interruption of
service, or similar conditions make periodic painting or maintenance
difficult. To minimize distortion, assemblies to be galvanized shall be
designed in accordance with the provisions of The Design of Products To Be Hot
Dip Galvanized After Fabrication, a publication of the American Hot Dip
Galvanizers Association.
9.3.2
Foundations. Foundations for antenna supporting structures shall
be designed in accordance with the requirements of NAVFAC DM-2 series and
NAVFAC DM-7 Series. Foundation design shall take into consideration antenna
erection procedures, as well as reactions due to service loads. Some typical
antenna erection procedures are outlined in NAVELEX 0101,104.
9.3.3
Appurtenances
9.3.3.1.
Guys. Structural design of guys shall conform to the MIL-HDBK-
1002/3. Detrimental effects of guys on antenna operating efficiency shall be
minimized in accordance with NAVELEX 0101,104. Turnbuckles, adjustable
sockets, or other take-up means shall be used at the lower ends of all guys.
9.3.3.2
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