| AS-1747/URN-20(V) |
|
| Physical
Dimensions |
|
| Height |
54
- 1/2 inches |
| Diameter |
65
inches |
| Weight |
480
lbs |
| Operating
Temperature |
-28
C to +95 C |
|
|
| Frequency
Range |
Transmit:
962 to 1024 MHz
Receive: 1025 to
1150 MHz |
| Input
Impedance |
50
ohms (nominal) |
| VSWR |
>
2:1 over freq range |
| Polarization |
Vertical |
| RF
Power Rating |
20
kilowatts at 2% duty cycle |
| Power
Requirement |
115
vac, 60 Hz., 1 phase for convenience outlet. All
other power and control voltages are supplied from
amplifier group. |
| Feed
Type |
Unbalanced,
coaxial cable |
| Input
Connector |
Type
C |
|
|
Description:
The AS-1747/URN-20(V) is a unit of the OA-7203/URN-20(V)
Series Antenna Groups. The antenna group consists of an
antenna, antenna pedestal, radome, and control amplifiers.
The antenna groups are shipboard antenna systems for use
with tactical navigation (TACAN) installations. The antenna
and pedestal are enclosed in a glass fiber reinforced
plastic protective radome. The antenna central array, spin
motor, rotating assembly, and bearing control servo assembly
are mounted on a single base in the pedestal assembly. This
base is maintained in a horizontal plane by a roll servo
system.
Installation: The antenna assembly should be
placed as high as possible on the ship's mast. It must be
above all objects in its immediate vicinity. Objects within
15 feet or less should not be higher than the lower edge of
the pedestal for optimum TACAN performance. The installing
activity must supply a base plate on which to mount the
pedestal. The "N" and "S" marks on the
pedestal must be lined up parallel to the ship's centerline
to an accuracy of 0.1 degree, with the "N" mark
facing forward. The system requires an input from the ship's
stable element to provide roll information for antenna
stabilization.
Considerations: The cable lengths between the
antenna and almplifier group must not exceed 200 feet. |
