| AS-1390/U |
|
| Physical
Dimensions |
|
| Height |
166
inches |
| Diameter |
14
inches |
| Weight |
98
lbs |
| Operating
Temperature |
unavailable |
|
|
| Frequency
Range |
|
| UHF
Comms |
225
to 400 MHz |
| Drone
Control |
400
to 550 MHz |
| IFF |
1000
to 1150 MHz |
| Input
Impedance |
50
ohms (nominal) |
| VSWR |
>
2:1 over freq range (Comms); > 1.8:1 (Drone
Control and IFF) |
| Polarization |
Vertical |
| RF
Power Rating |
|
| UHF
Comms |
2
kilowatts |
| Drone
Control |
2
kilowatts |
| IFF |
1
kilowatt |
| Power
Requirement |
None |
| Feed
Type |
Unbalanced,
coaxial cable |
| Input
Connectors |
1)
UHF comms - Type LC, special UG-352A/U
2) Drone control
- Type LC, special UG-352A/U.
3) IFF - Type N,
special UG-58A/U
4) Wind
indicating equipment- BFR-18-8P |
|
|
Description:
The AS-1390/U Antenna is a single vertical unit containing
three separate omnidirectional antennas. This assembly
consists of:
- A UHF communications
antenna identical in electromagnetic characteristics to
Navy Type AS-1018/URC Antenna (lower unit).
- A drone control
operations antenna identical to Navy Type AT-948/U
Antenna (middle assembly).
- An IFF Operations
antenna (upper unit).
The isolation between the
antennas is greater than 25 dB. The entire assembly and
internal transmission lines are completely enclosed in a
fiberglass mast. Provision is made for mounting a Navy Wind
Indicating Equipment, Type B, atop the antenna assembly.
Installation: The antenna assembly mounting
flange contains eight 7/8 inch diameter bolt holes on a
12-1/4 inch bolt circle. The antenna may be installed on the
ship's structure by a suitable mounting plate having
matching bolt holes. The mounting plate must have a center
hole to accommodate the antenna transmission lines and the
cable for the wind indicating equipment.
Considerations: The location of the AS-1390/U
antenna on board ship should be selected to provide maximum
coverage within the physical constraints of the ships
superstructure and other antennas. UHF propagation is
generally line-of-sight and antennas that are masked by
surrounding structures may produce limited coverage in
azimuth and/or elevation. The antenna should be purged at
the time of installation to remove any moisture or damp air
entrapped within the enclosure. Purging should be
accomplished in accordance with the procedures outlined in
the equipment technical manual. The mounting flange is
fitted with a pipe nipple for this purpose. The antenna is
designed to operate unpressurized; however, it may be
pressurized to 15 psi if necessary. Procedures for
pressurizing the antenna are also included in the technical
manual as are the cabling requirements for the wind
indicating equipment. |
