Dual Vertical Phased Array
DXE-DVA-B
DXE-DVA-160B-P - Dual Vertical Array system for 160 meters
DXE-DVA-80B-P - Dual Vertical Array system for 80 meters
DXE-DVA-60B-P - Dual Vertical Array system for 60 meters
DXE-DVA-40B-P - Dual Vertical Array system for 40 meters
DXE-DVA-30B-P - Dual Vertical Array system for 30 meters
DXE-DVA-20B-P - Dual Vertical Array system for 20 meters
DXE-DVA-17B-P - Dual Vertical Array system for 17 meters
DXE-DVA-15B-P - Dual Vertical Array system for 15 meters
DXE-DVA-12B-P - Dual Vertical Array system for 12 meters
DXE-DVA-10B-P - Dual Vertical Array system for 10 meters
DXE-DVA-B-INS Revision 1b
© DX Engineering 2021
1200 Southeast Ave. - Tallmadge, OH 44278 USA
Phone: (800) 777-0703 ∙ Tech Support and International: (330) 572-3200
Fax: (330) 572-3279 ∙ E-mail: DXEngineering@DXEngineering.com
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Introduction and General Information
Congratulations on your purchase of the DX Engineering Dual Vertical Phased Array System,
custom designed and tested to offer the best directional transmitting and receiving performance in
proportion to the space required. Advanced design, with a stable, clean and low-angle pattern makes
the DX Engineering Dual Vertical Phased Array (DVA) the finest dual element quarter-wave
monoband phased antenna system available. The DX Engineering Dual Vertical Phased Arrays are
advanced vertical antenna phasing systems that set new standards in two vertical element array
performance. DX Engineering Dual Vertical Phased Array system design eliminates the waste load
port of previous hybrid-type two-element systems, thus increasing array efficiency. Each monoband Dual Vertical Array system includes a sleek new Phasing Relay Unit and a new Control
Console. The model number of your system corresponds to the band for which it was manufactured.
There are 10 system models available that cover 160 through 10 meters:
Part Number
Band
Phasing Relay Unit and Control Console
DXE-DVA-160B-P
160 meters
DXE-DVA-80B-P
80 meters
DXE-DVA-60B-P
60 meters
DXE-DVA-40B-P
40 meters
DXE-DVA-30B-P
30 meters
DXE-DVA-20B-P
20 meters
DXE-DVA-17B-P
17 meters
DXE-DVA-15B-P
15 meters
DXE-DVA-12B-P
12 meters
DXE-DVA-10B-P
10 meters
The Phasing Relay Unit can be ordered without the DVA Control Console for each band:
Part Number
Band
Phasing Relay Unit
DXE-DVA-160B
160 meters
DXE-DVA-80B
80 meters
DXE-DVA-60B
60 meters
DXE-DVA-40B
40 meters
DXE-DVA-30B
30 meters
DXE-DVA-20B
20 meters
DXE-DVA-17B
17 meters
DXE-DVA-15B
15 meters
DXE-DVA-12B
12 meters
DXE-DVA-10B
10 meters
The Dual Vertical Array Control Console can be ordered without the
DVA Phasing Relay Unit:
DXE-EC-DVA - Control Console only for the
Dual Vertical Array System
DX Engineering Dual Vertical Phased Array (DVA) systems produce two enhanced End-Fire
Cardioid patterns and one Broadside-Omni pattern. New heavy-duty components handle 2 kW
continuous RF power with array performance at low SWR over a wide bandwidth. The Dual
Vertical Array end-fire directional patterns achieve a real front-to-back over 20 dB with typical
array forward gain up to 3 dB over a single vertical.
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Each DX Engineering Dual Vertical Phased Array’s mono-band weatherproof DVA Phasing Relay
Unit includes a clamp for mounting on a mounting pipe that is positioned directly between two
ground mounted, full-size, quarter-wave resonant verticals. The antennas must be located as
described in the installation section to provide switchable patterns in desired directions. The
forward lobes are reasonably wide eliminating the need for precise aiming while also providing
coverage of in-between directions.
The proper spacing between these user-supplied antennas is one-quarter wavelength free space, and
each should be installed with 40 or more ground radials; all antenna system parts are also available
from DX Engineering.
The two ground mounted vertical antennas must be resonant in the desired band of operation. Each
vertical element must be directly fed through 1/4-wave long 75Ω transmission lines. No additional
matching components or decoupling devices may be used, like Baluns or coils, between the
centrally located Dual Vertical Phasing Relay Unit and the verticals, as additional transmission line
lengths can reduce array performance.
DVA systems require the 75-ohm antenna feed cables to be electrically tuned to one-quarter
wavelength. Offered by DX Engineering as an option, these custom built PL-259 terminated cable
assemblies use the highest quality waterproof polyethylene jacket direct-burial DXE-11U low-loss
foam coax. These custom length coaxial cables are frequency specific, electronically tuned and
connect the DVA Phasing Relay Unit directly to each mono-band vertical antenna feed point and
radial system.
The vertical antennas must be series-fed at the base, 1/4-wave long and must be resonant. DX
Engineering offers vertical antennas that are well suited for this application. Above all, a properly
designed and installed radial system is necessary for maximum system performance.
The included companion DXE-EC-DVA Control Console is a three-position directional pattern
selector that operates on +13.8 Vdc and features a 3-position rotary switch, directional LED
indicators and scratch pads on the console for the user to write in their array end fire directions. The
DXE-EC-DVA Control Consoles require only a 3-conductor 20 AWG cable for connection to the
DVA Phasing Relay Unit.
DX Engineering DVA - Dual Vertical Array System Features
The Dual Vertical Array System is a monoband two element, three direction-switchable array
based on a two element end-fire/broadside combination of identical ground mounted vertical
elements. This antenna array system is capable of delivering pattern directional performance
superior to other systems in its class.
Custom design with stable and clean low-angle patterns
No dump power as on other types of phased arrays so all your power goes to the antenna
elements
Power Handling: 2 kW continuous
Directional performance - Two End Fire and one Broadside directions
Forward Gain (approximate as compared to a single vertical): 3 dB End-Fire, 1 dB
Broadside (Omni)
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Can be built with ground mounted monoband verticals to cover any single band
RF Connectors: Three SO-239 (UHF Female): Transmitter, Antenna 1, Antenna 2
Excellent signal-to-noise ratio
Directivity over a very wide frequency range in the band selected
Excellent relay contact reliability
DC powered control console allows system operation without AC power mains
Control Cable: 3 conductors, minimum 20 AWG
Control Wire Connections: Set screw connectors internal at the Control Console and a
removable external connector at the DVA Phasing Relay Unit
Cover on the DVA Phasing Relay Unit made from tough UV protected plastic
Stainless steel chassis and mounting plate on the Phasing Relay Unit
DVA Control Console uses +13.8 Vdc input has three LEDs and three position rotary
direction switch (Position 1, Broadside, Position 2)
Designed, manufactured and tested by DX Engineering
Parts Included
DVA Dual Vertical Array Phasing Relay Unit for band specified.
DXE-SSVC-2P Stainless Steel V-Clamp for mounting the DVA Phasing Relay Unit to a
mounting post between 1" and 2" OD
DXE-EC-DVA Dual Vertical Array Control Console
2.1 mm Power Plug with wires to connect to the station +12 to +13.8 Vdc filtered power
supply
Additional Parts Required, Not Supplied with the DVA Systems
Two identical Full Size, Ground Mounted, Quarter-wave, Monoband, Vertical Antenna
Elements
JTL-12555 - Jet-Lube SS-30 Anti-Oxidant for the vertical antenna elements & hardware
DXE-RG-11U Phasing Cables, 75-ohm, cut to the proper electrical length for the applicable
dual vertical array system center frequency
DXE-RADP-3 Radial Plate - one for each ground mounted vertical element
DXE-UHF-FDFB-KIT SecureMount™ Bulkhead Connector for a clean and quality
feedline connection, one for each Radial Plate
DXE-FP-WIRE-P Feedpoint Wire & Connector Assemblies, one for each vertical element
DXE- RADW Radial Wire for the required vertical antenna radials
GCL-1120-050 Copper Radial Cross Bonding Strap, 2” wide
COM-CW3 - Three Wire Control Cable - COM-CW-3 is 3-wire, 20 AWG, stranded copper
with a PVC jacket
Galvanized Mounting Pipe, 1 inch OD minimum to 2 inches OD maximum, for mounting
the Dual Vertical Array Phasing Relay Unit at the center of the array using the supplied
DXE-SSVC-2P Stainless Steel V-Clamp (see text for details)
3M Temflex Tape and Scotch Super 33 Tape for Weatherproofing the coaxial cable
connections
DXE-400MAX or DXE-213U or equivalent, 50-ohm coaxial cable for the array main
feedline from the transceiver to the Phasing Relay Unit
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Manual Updates
Every effort is made to supply the latest manual revision with each product. Occasionally a manual
will be updated between the time your DX Engineering product is shipped and when you receive it.
Please check the DX Engineering web site (www.dxengineering.com) for the latest revision manual.
Tools Required
1/2” nut driver or wrench (for the DXE-SSVC-2P V-Clamp)
Wire stripper for control lines
Small flat blade screwdriver for control line connections
Soldering Iron and Solder to join the two radial fields together where they meet
General Installation Information
The DVA Dual Vertical Array Phasing Relay Unit should be mounted to a customer supplied
mounting pipe at the center of the array, halfway between the two ground mounted monoband
verticals.
The DVA Dual Vertical Array Phasing Relay Unit has a built-in, stainless steel, pre-drilled
mounting flange to accommodate up to a 2 inch OD mounting pipe. The included DXE-SSVC-2P
Stainless Steel V-Bolt Saddle Clamp is for attaching the Phasing Relay Unit to the customer
supplied 1" to 2" OD mounting pipe. An optional DXE-CAVS-1P V-Bolt Saddle clamp can be
used for pipe from 3/4" to 1-3/4" inches OD. The Phasing Relay Unit can also be mounted on a
sturdy wooden post.
Note: JTL-12555 Jet-Lube SS-30 Anti-Seize must be used on all clamps, bolts and stainless steel
threaded hardware to prevent galling and to ensure proper tightening.
The Array Phasing Relay Unit must be mounted with cover upward and the control and coaxial
cable connections downward to prevent water from entering the box. The stainless steel base of the
Array Phasing Relay Unit has weep holes to allow condensation that may build up inside the unit to
leave. Additional weatherproofing protection may be used on the coaxial connections.
WARNING!
INSTALLATION OF ANY ANTENNAS NEAR POWER LINES IS DANGEROUS
Warning: Do not locate the antennas near overhead power lines or other electric light or power
circuits, or where they can come into contact with such circuits. When installing the antennas, take
extreme care not to come into contact with such circuits, because they may cause serious injury or
death. Make sure when you are digging, you are not near any buried utility lines.
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Overhead Power Line Safety
Before you begin working, check carefully for overhead power lines in the area you will be
working. Don't assume that wires are telephone or cable lines: check with your electric utility for
advice. Although overhead power lines may appear to be insulated, often these coverings are
intended only to protect metal wires from weather conditions and may not protect you from electric
shock
Keep your distance! Remember the 10-foot rule: When carrying and using ladders and other long
tools, keep them at least 10 feet away from all overhead lines - including any lines from the power
pole to your home.
Installation
Site Selection
Select mounting locations clear from power lines and structures by a minimum of height of the
ground mounted monoband antennas used plus 10 feet (for the 10 foot safety rule). Consider
overhead power lines, utility cables and wires. The monoband verticals should be mounted away
from local noise sources or other metallic objects which can re-radiate noise and affect the tuning,
radiation pattern and SWR. Determine the direction you want the array positioned. There should
also be a clear diameter from the ground mounted monoband antennas for the guying and radial
systems that will extend away from the antennas.
Topographical Considerations
Flat or gradually sloped land is best. Erecting the transmitting array on steeply sloped land or
uneven terrain might degrade performance. To avoid pattern degradation, antenna elements should
have reasonably similar elevations. It's recommended the maximum ground height difference
between any of the ground mounted vertical antennas in the array should be less than 20% of the
array diameter. For example, two 80 meter verticals 66 feet apart should be within 13 feet of level.
Every effort should be taken to make the elements symmetrical. Elements must be ground mounted,
similar or identical in construction and grounding. Elements should be mounted above any standing
water, but as close to the ground as possible. In general, the system will not be affected by trees or
foliage so long as the foliage is not near an element. The open ends or tips of the elements are
particularly sensitive to close branches or foliage. There should be a reasonably clear electrical path
for at least 1 wavelength in important receiving directions. The site should allow a radial system to
be as evenly distributed around each of the vertical elements as possible, although perfect symmetry
isn’t important so long as the radial connections are good.
Most amateur radio operators in the continental United States will want the system to point toward
Europe (NE) as a default (position 1). Therefore the system described in this manual will be laid out
with vertical antenna elements 1 to the Northeast in a line going to antenna 2 toward the Southwest.
Note: This array, like all dual phased vertical set ups, has a fairly wide flat forward lobe. This
means exact direction headings are generally not critical. We should still remember there is a
difference between True North and Magnetic or Compass North. Without going into all of the
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details, you want your system aligned to True North. Depending on your location you can check
your position using various geological, topographical or aviation maps to determine True North.
If your location has more than 10 degrees magnetic declination, you may want to correct for it.
Declinations below ten degrees can be safely ignored.
If you know your longitude and latitude, you can then pinpoint yourself on an aircraft navigation or
geological map. If you don't know your longitude and latitude, you can find that information on
many of the map services available on the internet, or use a GPS.
Site Selection in Relation to Noise Sources
Since the array is generally used for both transmitting and receiving, you should listen to desired
bands and identify any sources of unwanted noise. Elimination of noise sources is required for
optimal receiving results. If noise sources cannot be eliminated, then locate the antenna array as far
away from noise sources as possible.
Since this array is directional, locate the array so the rear of the array is pointing towards the
dominant noise source. This ensures the array has maximum suppression of noise when beaming in
the primary listening direction. For example, if you primarily want to work Europeans from the
eastern USA (Northeast direction), try to position the array so the dominant local noise is Southwest
of the array. There is no advantage at all when an array points into the noise, no matter what the
array gain is.
Gain does not generally matter, only the ratio of signal response to noise response changes S/N
ratio. The only way S/N ratio improves at HF is if the array nulls the noise more than it nulls the
desired signal.
The second-best location for the array is when the noise source is as far as possible to either side of
the array. If you look at patterns, the ideal receiving location for the array is one that places
undesired noise in a deep null area.
If your location doesn’t have the usual noise sources (power lines, electric fences, etc.), locate the
array so that your other transmitting antennas and buildings are off the back or side of the primary
array direction.
Consider these things about noise sources:
If noise is not evenly distributed, performance will depend on the gain difference between
the desired signal direction (azimuth and elevation) and average gain in the direction of
noise.
If noise predominantly arrives from the direction and angle of desired signals (assuming
polarization of signals and noise are the same) there will be no improvement in the signal-tonoise ratio.
If the noise originates in the near-field of the antenna, everything becomes unpredictable. This is a
good case for the use of separate receiving antennas placed as far from noise sources (such as power
lines) as possible.
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Monoband Antennas for a Dual Vertical Array System
The following are some suggested DX Engineering and COMTEK full size quarter-wave monoband vertical
antennas are an ideal match for top performance in a dual vertical array system. You’ll need 2 ground
mounted verticals.
BAND
Part Number
Description
Comments
160
DXE-160VA-1
Vertical, 160 meters, 160m, 5,000 W, Pivoting Fixture Mount, 55.00
ft. Height, Kit
Need two
80
DXE-7580FS-VA-1
80 Meter Quarter-Wave Vertical, 80m, Full Size, 68 ft. Height,
5 kW, Stainless Steel Tilt Base, Kit
Need two
DXE-7580FS-VA-2
80 Meter QW Vertical, 80m, Self-Supporting Heavy-Duty,
Full Size, 68 ft., 5 kW, HD Pivoting Base, Kit
Need two
DXE-7580FS-VA-3
80 M QW Vertical, 80m, Self-Supporting Heavy-Duty PLUS, Full
Size 68 ft., 5 kW, HD Pivoting Base, Kit
Need two
60
DXE-7580FS-VA-1
80 Meter Quarter-Wave Vertical, 80m, Full Size, 68 ft. Height,
5 kW, Stainless Steel Tilt Base, Kit
Need two. Shorten overall
length for 60 meters
40
COM-40VA-2P
Vertical, HF, Monoband, Adjustable, 3000 W, 40 meters,
Non-tilt Bracket Mount, 34.3 ft Height, Pair
30
COM-30VA-2P
Vertical, HF, Monoband, Adjustable, 3,000 W, 30 meters,
Non-tilt Bracket Mount, 24 ft Height, Pair
20
COM-20VA-2P
Vertical, HF, Monoband, Adjustable, 3,000 W, 20 meters,
Non-tilt Bracket Mount, 17.0 ft. Height, Pair
17
COM-20VA-2P
Vertical, HF, Monoband, Adjustable, 3,000 W, 20 meters,
Non-tilt Bracket Mount, 17.0 ft. Height, Pair
Shorten overall length for
band desired.
15
12
10
Guying is always recommended for vertical antennas, especially in windy environmental conditions.
Please visit www.DXEngineering.com for details on the vertical antennas listed above.
The Dual Monoband Vertical Antenna Layout
The two full size quarter-wave ground mounted monoband
vertical antennas making up the dual vertical array system
must be properly positioned. The example on the right shows
a typical set up where antenna 1 is toward the NE and antenna
2 is toward the SW. You must adhere to the dimensions
shown on the next page for optimum performance. The
placement of the two vertical antennas in relation to each
other is somewhat critical. If the dimensions are more than
five percent out of specification, system performance can
suffer.
The formula for determining the distance between each
antenna (1/4-wavelength) is:
246
L in Feet =
▬▬▬
MHz
Use 246 divided by the Frequency in MHz = Length in feet
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