the feedhorn. The vertical angle of radiation (elevation above or below the horizon) may be mechanically adjusted using
the tilt tope of the tilting assembly.
The antenna adapter (configuration A only) is provided for mounting the AS-
1425/GRC on Mast Assembly AB-577/GRC. Four guy cable assemblies are provided to stabilize the AS-1425/GRC
when mounted on a mast. An alternating current (ac) power connector is provided so that 115 volts, 60 Hertz (Hz) may
be applied to the deicer equipment which is permanently mounted on the feedhorn. Radio frequency (rf) power to the
feedhorn is applied through waveguide components which are selected according to the requirements of specific
Each AS-1425/GRC antenna has two 4 1/2-foot sections of flexible Waveguide Assembly CG-3251/GRC, six 15-
foot sections of flexible Waveguide Assembly CG-3307/ GRC, and one Waveguide Assembly CG-3250/GRC (a drain
section). The 15-foot sections are stowed on special reels, and are not shown in figure 1-1. The waveguides are secured
to the mast (when mast mounted) by the mast-to-waveguide clamp assemblies. One guy (messenger cable) is used with
the cable hangers assemblies to support the waveguide run to the shelter in which the associated radio set is usually
Description of Operating Accessories
Operating accessories of the AS-1425/GRC are necessary for installation, operation, or maintenance and normally
consist of the following:
a. A mast, such as Mast Assemblies AB-621/G or AB-577/G, is required if the AS-1425/GRC is to be elevated to
clear obstructions, powerlines, etc.
A level assembly and spanner wrench are required for leveling the mast assembly and for adjusting the position
of the antenna (in azimuth) on the mast assembly (TM 11-5820-568-12) .
Special tools for other mast assemblies are listed in the technical manual for the specific mast assembly
or associated radio set.
Antenna AS-1425/GRC provides the transmitting and receiving antenna elements of a radio communications network.
When used for direct line-of-sight communications, an AS-1425/GRC is required at each of the two terminals. When a
relay station is used, four AS-1425/GRC antennas are required--one at each terminal and two at the relay station. In
each of these configurations, the AS-1425/GRC may be used with