AS-3226B/URC
VTM-01-009-RevE
Figure 3-1
Balancing Transformer Arrangement
SECTION 3
FUNCTIONAL DESCRIPTION
3-1. FUNCTIONAL DESCRIPTION
.
The AS-3226B/URC VHF Antenna is a general purpose, high performance, vertically
polarized, broadband, balanced dipole covering the 30 to 88 MHz frequency range. It is
used for either transmitting or receiving. The antenna is a cylindrical dipole radiator fed
by a conventional coaxial RF line. Integrated into the antenna structure is a balancing
transformer arrangement, which allows the dipole radiator to be fed in a balanced manner
eliminating extraneous line currents. (see figure 3-1).
a. Electrical Balance. The electrical balance provided for the radiating elements permits
feeding the antenna directly by 50 ohm coaxial cable. The input VSWR is less than
3.0:1 on 50 ohms.
b. Radiation Patterns. Radiation patterns for the antenna correspond to those of a
balanced dipole in free space. Coverage in the plane perpendicular to the radiating
elements is omnidirectional. Figure 8 coverage, with nulls off the ends of the
elements, is provided in the plane of the radiators. The inherent broadband impedance
characteristics make the antenna relatively insensitive to its mounting environment and
minimize azimuth and zenith pattern distortion at any location.
Valcom Manufacturing Group Inc
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