| AS-2802/SRC |
|
| Physical
Dimensions |
Antenna |
| Height |
393
inches |
| Diameter |
Cone:
252 inches; Disc: 216 inches |
| Weight |
2200
lbs |
| Operating
Temperature |
-54
C to +65 C |
|
Matching
Network |
| Height |
21
- 3/16 inches |
| Width |
37
- 1/8 inches |
| Depth |
28
- 1/8 inches |
|
|
| Frequency
Range |
4
to 12 MHz and 10 to 30 MHz |
| Input
Impedance |
50
ohms (nominal) |
| VSWR |
Matching
network supplied to limit VSWR to not greater than
216:1 over frequency range. |
| Polarization |
Vertical |
| RF
Power Rating |
12
kilowatts (average) |
| Power
Requirement |
None |
| Feed
Type |
Unbalanced,
coaxial cable |
| Input
Connector |
1
- 5/8 inch EIA Flange |
|
|
Description:
The AS-2802/SRC antenna is an omnidirectional broadband
discage antenna initially designed for installation on LHA
amphibious assault ships. The discage structure consists of
two truncated wire rope cones constructed base-to-base and
supported by a central mast. The lower portion of the
structure functions as a cage monopole for the 4 to 12 MHz
frequency range. The upper portion operates as a discone
radiator in the 10 to 30 MHz frequency range. Matching
networks are supplied to limit the VSWR to not greater than
3:1 at each feed point. Vinyl covered phosphor bronze wire
rope is used for the wire portions of the antenna. The
support mast and other members are aluminum. The antenna may
be used with any transmitting and/or receiving equipment
designed to operate within its frequency range and RF power
handling limitations.
Installation: The base of the mast section is
welded directly to the ship's deck. Eight gussets, equally
spaced around the circumference of the mast, are required
for strengthening. Eight insulated guys, equally spaced
around the circumference, are required from the lower
spreader to the ships deck. After the antenna has been set
in position and assembled the wire rope sections must be
stressed equally by use of the eight turnbuckles supplied
with the rope sections. Various mechanical fittings require
torque adjustments in accordance with the manufacturer's .
specifications during final installation.
Considerations: The antenna should be located
in an area as free as possible from surrounding structures
and other antennas. Ship's structures in the vicinity of
antennas cause radiation pattern distortion and a consequent
loss of omnidirectional characteristics. The close proximity
of other antennas increases the degree of mutual coupling
between the systems. The matching network should be located
close to the base of the antenna in order to keep the
connection from the matching unit to the antenna as short as
possible. |
