•Medium to long range
omnidirectional coverage
• Horizontally polarized to eliminate
ground loss
• High true power gain
• Rugged construction
Communicators hav e long needed a broadband, omnidirectional,
HF antenna with the highest possible power gain. Vertically
polarized antennas traditionally used for HF omnidirectional
cov erage suffer serious ground losses (up to 8 dB) or poor pattern
directivity, or both.
The Model 540 is a horizontally polarized, omnidirectional log
periodic antenna embodying a radical new design, and having
remarkably high power gain. Horizontal polarization virtually
eliminates ground losses, and arraying in elevation provides
superior directivity. At 30 MHz power gain exceeds 10 dBi over
average soil, decreasing to 7 dBi at 3.6 MHz. VSWR does not
exceed 2.5:1 over the 3.6 to 30 MHz spectrum. Performance is
virtually independent of the ground beneath the antenna, and no
ground screen is required.
In additional to the Model 540’s exceptional gain and
omnidirectional pattern, its unique confi guration provides a
broad elevation plane lobe with high angle radiation at lower
frequencies, and a narrow lobe with low angle radiation at
higher frequencies. The actual take-off angles closely parallel
the statistical ideal so that the Model 540 is superb for roll-call,
shore-ship, and ground-air applications involving transmission
paths greater than 1,000 km.
As a result of its high omnidirectional gain, a single Model 540
can replace up to 6 directional horizontal log-periodic antennas
with enormous land and capital savings. It can also substitute
for a rotatable log-periodic with almost no loss in performance
and none of the mechanical maintenance or reliability problems
normally associated with this type of antenna.
MODEL
540
Omni-Gain AntennaTM
As with all TCI antennas, the Model 540 employs high quality,
exhaustively tested components and materials. All radiators,
feedlines, and catenaries are of Alumoweld, a wire composed of
a high strength steel core and a highly conductive, corrosion
resistant, welded coasting of aluminum. All feedline and radiator
tip insulators are made of high strength glazed alumina, a
material with an extremely low loss tangent (.001) and virtually
impervious to the effects of ultraviolet radiation, dirt, and salt
spray. No fi berglass is used in the antenna.
The antenna is supplied in preassembled kit form with all
required materials including towers, guys, guy anchors, radiating
curtain, feed hardware, balun, and steel mounting hardware to be
imbedded in the concrete foundations, but not including concrete
or concrete reinforcing steel.
U.S. Patent No. 3,257,661
540-220301© TCI, 2001
Data and specifi cations subject to change without notice.
www.tcibr.com
Specifi cations
540-1 540-2
Polarization .............Horizontal Horizontal
Frequency ...............3.6–30 MHz 4.0–30 MHz
VSWR....................... 2.0:1 nominal 2.0:1 nominal
2.5:1 maximum 2.5:1 maximum
Power Gain.............. 7 dBi at 3.6 MHz 6 dBi at 4 MHz
10.5 dBi at 30 MHz 10 dBi at 30 MHz
Take-Off Angle ........30° at 3.6 MHz 38° at 4 MHz
9° at 30 MHz 10° at 30 MHz
Azimuth Plane
Pattern .....................Circular within 1 dB Circular within 1 dB
Height ......................36.6 m (120 ft.) 30.2 m (99 ft.)
Size ..........................87.6 m (287.2 ft.) 90.2 m (269 ft.)
by 87.6 m by 90.2 m
(287.2 ft.) (269 ft.)
Ground Screen........None None
Environmental.........All versions designed in accordance with
EIA RS-222C for loading of:
Standard Towers.....193 Km/h (120 mi/h) wind, no ice; 112
Km/h (70 mi/h) wind, 12 mm (1/2”) radial
ice. Also complies with EIA specifi cation
EIA-222-E for the indicated wind speeds at
the top of the masts.
Heavy Towers..........For Model 540-1, 225 Km/h (140 mi/h)
wind no ice; 124 Km/h (90 mi/h) wind
12 mm (1/2”) radial ice.
47300 Kato Road, Fremont, California 94538, USA • 1 800 824-8074 (USA) • Tel 1 510 687-6100 • Fax 1 510 687-6101
The table above compares performance of the Model 540 with
that of a typical vertically polarized inverted cone, the TCI Model
505. The Model 540 signifi cantly outperforms it.
Power Gain at Power Gain at Power Gain at
Path TOA 3.6 MHz (dBi)† 12 MHz (dBi)† 22 MHz (dBi)†
Length 540-1 505 540-1 505 540-1 505
1000 km 28° +7 +1 +4 +1 +4 +2
1600 km 17° +5 +2 +7 –4 +8 +1
2200 km 10° +1 –2 +5 –3 +10 –3
†Gain calculated with antenna over average ground.
Model Input Power Handling
Number Impedance Handling Connector
540-N-02 50 ohms Receive Type N
540-N-06 50 ohms 1 kW Avg. / 2 kW PEP Type N
540-N-28 50 ohms 5 kW Avg. / 10 kW PEP 7/8” EIA Female
540-N-03 50 ohms 10 kW Avg. / 50 kW PEP 15/8” EIA Female
540-N-09 50 ohms 20 kW Avg. /40 kW PEP 15/8” EIA Female
540-N-04 50 ohms 25 kW Avg. /50 kW PEP 15/8” EIA Female
540-N-05 50 ohms 25 kW Avg. / 100 kW PEP 31/8” EIA Female
Nomenclature, 540-2-05, AS-4133/F
Power and Impedance Data
ELEVATION PATTERNS power gain in dBi, Model 540-1
NOTE: Balun support pole, normally class 1
Douglas Fir, is required for transmitting
but not supplied by TCI. Check with TCI
for specifi c requirements.
