DX Engineering DVA Dual Vertical Array Systems are advanced HF phasing devices that have set new standards in two-element array performance. The DVA is a new vertical antenna phasing system that eliminates the wasteful dump load of legacy hybrid units. This optimized phasing system is specially designed to create a directional antenna with two identical ground-mounted quarter-wave verticals. Dual Vertical Array Systems include a compact DVA Phasing Relay Unit made specifically for a single band, 160 through 10 meters, and an EC-DVA Directional Control Console.
Along with improved performance, another great advantage of a Dual Vertical Array is achieving a directional antenna without requiring a tower and rotator for a large Yagi antenna. Plus, a ground-mounted phased array has far less visual impact. Especially for the low bands, including 40 meters, a Dual Vertical Array provides the phasing system for a mechanically and financially practical directional antenna that is much easier to install than a tower and beam. Mono-band arrays achieve patterns and performance that multi-band systems cannot.
DX Engineering Dual Vertical Arrays systems offer improved performance in all respects, replacing the legacy COMTEK PVS-2. The installed system produces two opposite End-Fire Cardioid patterns and one Broadside-Omni pattern, as shown here. Heavy-duty relay unit components handle over 2 kW continuous RF power for enhanced performance at low SWR over a wide bandwidth. 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. This DVA system provides excellent bandwidth under 2:1 SWR, covering about 300 kHz of the 80 meter band, dependent upon the verticals installed.
The weatherproof DVA Phasing Relay Unit includes a chassis bracket, with stainless steel clamp and hardware, for mounting on a 1 to 2 in. OD pipe or post. When mounted, the black UV resistant cover protects the chassis and downward facing connectors. Each relay unit has three SO-239 connectors, two for the array element 75 ohm feedlines and one to the station. A removable four-conductor connector is provided for the control cable with field-serviceable compression screw wire connections.
The companion DXE-EC-DVA Directional Control Console has a 3-position rotary switch to select opposite end-fire or broadside patterns, and features direction selection LED indicators with two erasable labeling pads. DXE-EC-DVA Control Consoles require a 3-conductor 20 AWG cable, wired internally, to connect to the DVA Phasing Relay Unit and the system operates on 13.8 Vdc.
Representation of a two-vertical ground radial system
The DVA Relay Unit is unit is typically placed directly between your two ground-mounted, full-size, quarter-wave resonant vertical elements that must be base insulated (shunt-fed towers cannot be used). Vertical element spacing must be one-quarter wavelength free space at the array target frequency and each element should be installed with 40 or more ground radials. DX Engineering offers tower sections and aluminum tubing to create your elements and Vertical antenna accessories to build your array with top quality components.
DVA systems require 75-ohm antenna feed cables, electrically tuned to one-quarter wavelength at the target center frequency of the array. Offered by DX Engineering as an option, our custom built PL-259 terminated cable assemblies use the highest quality waterproof polyethylene jacket direct-burial DXE-11U low-loss foam coax. These are frequency specific, electronically tuned cables that connect from the DVA Phasing Relay Unit to each vertical element feedpoint.
DX Engineering's 80 Meter Dual Vertical Array phasing systems are typically in stock, as are the 40 meter and 160 meter systems. DVA systems for the other HF bands, 60, 30, 20, 17, 15, 12 and 10 meters will be available by special order. Call DX Engineering to discuss system plans and requirements. Your phased array performance and pattern results will vary due to antenna element surroundings, sky wave propagation and band conditions. Additional information is available in the Dual Vertical Array Instruction Manual.
These are great directional antenna systems for temporary and Field Day operation, as well as for permanent builds, because they are so much easier to install than a beam! If you are dissatisfied with your present system, are ready for an upgrade, or just need to get out of the tower game, the DX Engineering DVA is your answer! Refurbish an existing antenna system, equip your temporary array, or build a new phased array with a DVA. It’s all on the ground, safe and simple: DX Engineering Dual Vertical Arrays offer a better way to enjoy a high-performance mono-band directional antenna.