DX Engineering DXE-40VA-1 User manual

40 Meter
Vertical Antenna
DXE-40VA-1
DXE-40VA-1-INS Revision 16d
© DX Engineering 2013
P.O. Box 1491 ∙ Akron, OH 44309-1491 USA
Phone: [phone] ∙ Tech Support and International: [phone]
Fax: [phone] ∙ E-mail: [email protected]

- 1 -
Table of Contents
Introduction
2
Features
2
Additional Material Needed, Not Supplied
2
Optional Equipment
3
Parts List
3
Tools Required
4
Warning
4
Overhead Power Line Safety
4
Installation
5
Mounting Pipe
5
Radial System
5
Site Selection
6
Assembly
6
Radial Plate to Mounting Pipe
7
Attaching Ground Radial Wires to the Radial Plate
7
Base Section
8
Base Section to Mounting Pipe
10
Assembling the Vertical Sections
11
Mating the Vertical Sections to the Base Section
15
Feedline Connections
15
Top Hat Assembly –40 Meter Operation
16
Installing the Top Hat –40 Meter Operation
17
Tuning the Vertical
17
Appendix A - Radial Plate
18
Appendix B - Tilt Base
19
Appendix C - Vertical Feedline Current Choke
20
Optional Accessory Items
21
Technical Support and Warranty
23

- 2 -
Introduction
The DX Engineering DXE-40VA-1 is a self-supporting vertical antenna system that operates over
the entire 40 meter band with an SWR of under 1.5:1, yet is less than 24 feet high. It can easily be
configured to operate on the 30 meter band with an equally low SWR by a simply removing the
capacity hat. This vertical uses no traps, coils or linear loading elements. Designed with 6063
corrosion-resistant aluminum tubing and stainless steel hardware, this antenna is very durable and
attractive.
The DXE-40VA-1 vertical antenna system includes the antenna elements, capacity hat, mounting
plate and stainless steel hardware and clamps.
Features
Full band coverage on 40 or 30 meters with SWR under 1.5:1 No Tuner needed
Bandwidth greater than 750 kHz with SWR under 2:1
Slow taper for wider bandwidth
Tunable above and below 7 MHz range for MARS and CAP frequencies
No Coils or Traps - Maximum Radiation Efficiency
Power Handling up to 5 kW
Less than 24 ft overall height
Additional Material Needed, Not Supplied:
Antenna Mounting - Steel tube, 1-3/4"″OD, 0.25″wall thickness, 4 feet long. The
standard 1-1/4" galvanized water pipe (with its approximate 1.7" OD) is just fine for this
application and can usually be found at your local home building supply store.
Quik-Set Concrete - Mounting pipe installation
DXE-P8A - Penetrox™ A - To ensure good electrical connection for aluminum
UMI-81343 - Anti-Seize compound - used on the threads of the Stainless Steel Hardware to
prevent galling and aid in proper tightening torque.
DXE-RADP-3 - Radial Plate: The most effective way to connect those essential radial
wires and the feedline coax to your vertical antenna for the maximum efficiency and
strongest signals. All stainless construction and includes 20 sets of radial connection
hardware. Additional radial components available.
DXE-RAD-1HWK - Stainless Steel Radial Plate Hardware: Additional 20 Sets of all
Stainless Steel Radial Hardware for use with the DX Engineering Radial Plate
DXE-RADW - Radial Wire Kits and Components. To achieve optimal performance with a
ground-mounted vertical, install as many radials as possible. These radial wire kits use 14
gage stranded copper wire with a relaxed black PVC insulation that is UV resistant, hard to
see and lays down easily, unlike the wire that is commonly available at the big box stores. It
will last much longer in contact with soil than bare wire.
DXE-SSVC-2P Stainless Steel V-Clamp. One for the DXE-RADP-3 Radial Plate and one
for the DXE-VFCC-H05-A Vertical Feedline Current Choke, if used.
DXE-VFCC-H05-A - 2/5 kW Vertical Feedline Current Choke for Coaxially Fed 50 Ω
HF Vertical Antennas - Prevents unwanted RFI by eliminating feedline current and
radiation allowing all power to go to the antenna improving efficiency. Reduces noise or
unwanted signals picked-up by the feedline and overcome a less than optimal ground system

- 3 -
The V-Clamp, used to mount the VFCC, part number DXE-VFCC-2P, is not included and
must be purchased separately.
DXE-8X19-RT Feed Point Cable and DXE-363-SST Bulkhead connector for a clean and
quality feedline connection. Not required when using the DXE-VFCC-H05-A.
Guy Rope and Anchors –DXE-GUY200-KIT contains 4 screw-in earth anchors and two
100 foot rolls of Dacron/polyester rope to guy the DXE-40VA-1 in four directions.
Additional guy rope is available from DX Engineering in several diameters and lengths.
Optional Equipment
DXE-TB-4P Tilt Base –This patented (US Patent 7,432,875) Tilt Base makes it easy for
one person to raise and lower the vertical. All stainless steel construction
Parts List for the DXE-40VA-1
Description
Qty.
Description
Qty.
Base Assembly
Antenna Assembly
Mast Mount Channel
1
2" / 1-7/8" Nested Double Tube Assembly
72" long - Slit both ends
1
Base Plate
1
1-3/4" / 1-5/8" / 1-1/2" x 24" long
Nested Triple Tube Base Section Tube
1
1-3/4" / 1-5/8" Nested Double Tube Assembly
72" long - Slit one end
1
1/4-20 x 2" Hex Head Bolt
4
1-1/2" x 72" - Slit one end
1
Aluminum Spacer
4
1-3/8" x 72"
1
1/4-20 Hex nut
4
DXE-ECL-16SS Element Clamp
1
1/4" Split Washer
4
DXE-ECL-20SS Element Clamp
1
1/4" Flat Washer
8
DXE-ECL-24SS Element Clamp
2
DXE-SAD-175S - Saddle Clamp Kit, 1.75"
2
1.312" Black Vinyl Cap.
1
DXE-CAVS-1P - V-Bolt Saddle Clamp
2
1.687" Black Vinyl Cap.
1
Capacitance Hat Assembly
Feedpoint Connection
DXE-MPH-150 Mult-Hub (US Pat.No 7,321,340)
1
1/4-20 x 1" Hex Head Bolt
1
1/4-20 x 1" Hex Bolt
3
Mast Mount Bar for Pigtail Attachment
1
1/4-20 x 1-1/4" Socket Head Cap Screw
3
1/4-20 Hex nut
2
1/4-20 Square nut
3
1/4" Star Washer
4
1/4-20 Nut
6
1/4" Flat Washer
2
1/4" Fender Washer, 1" OD
6
#10 Flat Washer
1
1/4" Flat Washer
3
10-24 Hex nut
1
1/4" Split Washer
6
#10 Star Washer
1
Whip Element
6
10-24 x 1/2" Hex Bolt
1
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.

- 4 -
Tools Required
Two 7/16”wrenches, (one of them should be open-end)
1/2 inch and 7/16 inch socket and drive
3/16" Allen wrench
Medium size screwdriver or 5/16”nut driver for the element clamps
3/16”and 1/4”nut drivers or wrenches
Tape measure and Felt-tip marker
The use of an antenna analyzer such as the MFJ-259B will facilitate the fine tuning of the
vertical. Ground conductivity as well as the number of radials and their length can affect
tuning parameters. A minimum of 16 radials 35 ft long should be used for reasonable
performance.
WARNING!
INSTALLATION OF ANY ANTENNA NEAR POWER LINES IS DANGEROUS
Warning:Do not locate the antenna near overhead power lines or other electric light or power
circuits, or where it can come into contact with such circuits. When installing the antenna, take
extreme care not to come into contact with such circuits, because they may cause serious injury or
death.
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.

- 5 -
Installation
Mounting Pipe
Use a customer supplied thick-walled galvanized steel mounting pipe at least 4
feet long. This will allow approximately 2 feet or more to be below ground and
approximately 2 feet above ground. A thick-walled steel pipe 1-3/4" OD is
recommended with a minimum thickness of 1/8" (1/4" preferred) should be
used. The standard 1-1/4" galvanized water pipe (with its approximate 1.7"
OD) is just fine for this application and can usually be found at your local home
building supply store. When using the optional DXE-TB-4P Tilt base a
mounting pipe of up to 2" OD may be used. For permanent mounting, use a
post-hole digger to make the hole deep enough to accommodate 2 feet of pipe
and a couple inches of gravel at the bottom for drainage. Set the pipe on the
gravel, use the pre-mix concrete to fill around the pipe, adding water and mixing
as you fill or mix the concrete first, then pour in the hole. Fill the hole until the concrete is level
with the ground around it. Use a level as you fill the hole to be sure the pipe is straight. Allow to set
overnight. Your location, landscape and ground conditions may require different mounting solutions
in order to have the steel mounting pipe and the vertical antenna in a secure position.
Note: Galvanized steel, rather than aluminum, is much more suitable for mounting in concrete.
Aluminum will quickly corrode due to incompatibility with the materials used to make concrete.
Radial System
The use of a radial system is a key requirement for a high performance quarter wave vertical
antenna system. With a vertical antenna system, the radials are the second half of the antenna. The
radials contribute to the radiation efficiency of the entire vertical antenna system.
At a minimum, 20 radials, each 32 feet long, should be used with this antenna. Using 32 radials at
32 feet long is preferred and highly recommended. The extra radials may help overcome unknown
poor-soil conditions, improve efficiency, and ensure the best performance possible from the vertical
antenna. Longer radials should be used for improved performance on the lowest frequency to be
used if your plans call for 60 or more radials. DXE-RADW Radial Wire, a stranded 14 gauge
relaxed PVC insulated copper wire is suggested for the best results.
The wire radials should placed as symmetrically as possible around the vertical
antenna and spaced evenly, regardless of how many radials are used. Do not cross
or bunch any radial wires as this nullifies their effectiveness. If you have limited
space, put in as many straight radials as you can. The radial wires can be attached to
the vertical using the lower left V-Bolt Saddle nut. The radials must be connected to
the shield of your feedline which then connect to the other U-bolt. The DXE-
RADP-3 Stainless Steel Radial Plate is an ideal optional item which provides an
excellent system for attaching radial wires to your vertical antenna system.
Radial wires can be laid on the roots of the grass using DXE-STPL Radial Wire Anchor Pins, or
Lawn Staples to hold them down. Using enough of the staples will ensure the wires will not be
snagged by mowers, people, or animals. Grass will quickly overgrow the radials and they will be
virtually impossible to see. An article describing this process is available the DX Engineering
website www.dxengineering.com in the Tech Info section. Radials can also be buried just under the
surface by using a power edger to make a slit in the soil.

- 6 -
Site Selection
Select a mounting location clear from power lines, structures and other antennas by a minimum of
35 feet (added space for the 10 foot safety rule). Consider overhead power lines, utility cables
and wires. The further away the vertical is mounted from local noise sources or other metallic
objects, which can re-radiate noise and affect the tuning, radiation pattern and SWR, the better.
When using the Tilt Base determine the direction you want the antenna to tilt down and make sure
there is adequate clearance. There should be sufficient room for a radial system that will extend
away from the antenna equally in all directions, if possible.
Assembly
The DXE-40VA-1 shipping box contains vertical element tubing sections, an insulated U-channel,
the mounting plate, stainless steel hardware and 6 top-hat rods packaged inside some of the larger
element tubing sections. Some of the smaller element tubes may be inside larger ones.
Carefully unbox the antenna and separate the various element tubes. All the element tube sections
are 72" long except the base assembly which is 24" long. Remove the 6 top-hat rods from inside the
element tubes. Unwrap the U-channel bracket and mounting plate. Separate the individually marked
hardware bags and lay them out for easy identification. The vinyl caps for the mounting pipe and
top element section should be installed after assembly of the vertical is complete.
Note: DXE-P8A Penetrox™A Anti-Oxidant should be used between all antenna element
sections. Penetrox™ A is an electrical joint compound to affect a substantial electrical
connection between metal parts such as telescoping aluminum tubing or other antenna
pieces. It ensures high conductivity at all voltage levels by displacing moisture and
preventing corrosion or oxidation.
UMI-81343 Never-Seez® or DXE-NSBT8 Anti-Seize should be used on all clamps,
bolts and stainless steel threaded hardware to prevent galling and to ensure proper
tightening.
Note: The following assembly instructions are based on using a 2" OD Mounting Pipe, with the
optional DXE-RADP-3 Radial Plate. The standard 1-1/4" galvanized water pipe (with its
approximate 1.7" OD) is just fine for this application and can usually be found at your local
home building supply store.

- 7 -
Radial Plate to Mounting Pipe
Install the optional DXE-RADP-3 Radial Plate on the mounting pipe using an optional DXE-
SSVC-2P stainless steel V-Clamp as shown in Figure 1. The standard 1-1/4" galvanized water
pipe (with its approximate 17" OD) is just fine for this application and can usually be found at your
local home building supply store. Mount the Radial Plate so you have approximately 1" of space
between the bottom of the plate and the ground level. This will allow easy access to install the
radial wire hardware. The DXE-RADP-3 Radial Plate comes with 20 sets of stainless steel
hardware for mounting the radial wires. Mount the plate as shown in relation to how the Tilt Base
is mounted.
Figure - 1 - DXE-RADP-3 Radial Plate Installation
Attaching Ground Radial Wires to the Radial Plate
Using the 20 sets of supplied 1/4" stainless steel hardware (Bolt, Star Washer, Flat Washer, Split
Washer, Nut) connect the optional ground radial wires to the DXE-RADP-3 Radial Plate as shown
in Figure 2. Additional hardware kits are available (DXE-RADP-1HWK) that contain 20 sets of
Radial Plate Hardware.
There are optional Radial Wire Kits available. DXE-RADW-500K/BD contains a 500 foot spool
of 14 gauge PVC insulated black copper stranded wire with 20 Terminal Lugs and 100 Steel or
Biodegradable Lawn Staples. The DXE-RADW-1000K/BD Radial Wire Kit contains a 1,000 foot
spool of 14 gauge PVC insulated black copper stranded wire with 40 Terminal Lugs and 200 Steel
or Biodegradable Lawn Staples. RADW-20RT, -32RT or -65RT contain 20 each radial wires with
1/4" terminal attached. These kits come in 20 Ft, 32 Ft, or 65Ft lengths.

- 8 -
Depending on the number of radial wires used, space them out evenly around the Radial Plate. The
Radial Plate will accommodate up to 60 radial wires (60 laser drilled holes), or up to 120 radials if
doubled up.
Radial
Wire
Pattern
Figure - 2 - Radial Wire Hardware Installation
Base Section
The base section is made up of an insulated mounting channel, an aluminum mounting plate and the
base antenna element section which is a triple-wall tube 24" long, with holes drilled at one end.
Using Figure 3, attach the aluminum mounting plate to the back of the insulated channel. The base
hardware kit contains two sets of mounting bolts. Use the four 2" bolts, four flat washers, four lock
washers and four nuts to mount the included backing plate. If you have chosen to use the optional
TB-4P Tilt Base, refer to the DXE-TB-4P manual. You will be using a smaller mount plate.
Figure 3
From the inside of the channel, insert a 1-1/4" bolt with a flat washer through each of the middle
four holes, through the backing plate. Put on lock washers, spacers, flat washers and hex nuts.
Tighten firmly, but not enough to crush the insulated channel. The spacers are required when using
the optional DXE-TB-4P Tilt Base. The spacers are being installed here so they will not get lost.

- 9 -
Locate the short 24" triple wall base section element tube. Make sure the drilled feedpoint hardware
mounting holes are aligned. Install a star washer on the 1" bolt, and then insert the bolt through the
hole in the triple tubes from the inside, so the threads stick out. Put on a star washer, a flat washer,
and nut and tighten securely. Add another star washer, flat washer and nut, but do not tighten. The
feed wire attaches to this hardware. Figure 4 shows the completed feed assembly.
Note: Due to shifting during shipment, some alignment of the triple walls in the base section might
be necessary so the holes in all three walls line-up
Figure 4
Assemble the short base triple wall element section tube to the inside of the insulated mounting
channel using two of the included rounded saddle clamps as shown in Figures 3 and 5. Use the
outer upper and lower holes of the channel. The base section tube should extend about 1" beyond
the bottom of the insulated channel. Use Anti-Seize on all stainless threads to prevent galling which
can give a false feeling of being tight. However, with these clamps, it is not necessary to use
excessive torque to get an excellent mechanical connection. Once the lock washer has been
flattened out, the clamp is tight enough. Any clamp should be tightened evenly from side-to-side
with an equal amount of thread above the nut.
Figure 5

- 10 -
The feed wire bolt assembly can face either forward or to the rear, depending on how you will
connect the feedline. If you are using the optional DXE-8X16-RT pigtail to feed the vertical, orient
the feed wire bolt to the rear, facing the backing plate as shown in Figure 6.
Base Section to Mounting Pipe
Locate the two V-Saddle Clamps. Assemble them on the mounting plate as shown in Figure 4. We
have included an aluminum grounding kit to facilitate making the ground connection to the vertical.
(Use is optional unless the DXE-8X16-RT feedline pigtail is used). The kit contains a short
aluminum strap, large and small star washers along with a 1/2" x 10-24 bolt, and nut. To install,
place the larger star washer from the kit on the right side U-bolt of the lower V-Saddle clamp so it is
against the mounting plate. Put the aluminum strap on the U-bolt, then the flat and lock washer and
nut. Figure 5 shows the pigtail and aluminum ground strap mounting. To connect the feedline to the
pigtail, you will need a DXE-363-SST bulkhead adapter.
If you are not going to use the grounding bracket, the flat washers with the clamps should go against
the aluminum mounting plate, then the lock washers and nuts.
The mounting pipe installed in the ground should not extend above the insulated channel. Use
Never-Seez® on all stainless threads to prevent galling which can give a false feeling of being tight.
However, with these clamps it is not necessary to use excessive torque to get an excellent
mechanical connection. Once the lock washer has been flattened out, the clamp is tight enough. Any
clamp should be tightened evenly from side-to-side with an equal amount of thread visible above
the nut.
Figure 6 - Completed Vertical Base Mounting Grounding Bracket
Picture on left shown with optional feedline pigtail

- 11 -
Assembling the Vertical Sections
Note: DXE-P8A -Penetrox™A Anti-Oxidant should be used between all antenna element
sections. Penetrox™ A is an electrical joint compound to affect a substantial electrical
connection between metal parts such as telescoping aluminum tubing or other antenna
pieces. It ensures high conductivity at all voltage levels by displacing moisture and
preventing corrosion or oxidation
When assembling any telescoping aluminum tubing sections you should take the following steps:
1. Make sure the edges are smooth and not sharp. Deburring may be necessary, since burrs and
shavings can occur on seams as well as edges. All surfaces need to be completely smooth to
allow easy assembly of tubing sections.
Caution
Aluminum tubing edges can be very sharp.
Take precautions to ensure you do not get accidentally cut.
The raised particles and shavings that appear when the aluminum tubing is machined are
referred to as burrs, and the process by which they are removed is known as deburring.
Deburring is a finishing method used in manufacturing. Our aluminum tubing is machine cut on
both ends and machine slit on one end. Although DX Engineering manufactured aluminum
tubing is deburred, you should further assure that there are no ragged edges or protrusions.
Use the DXE-22166 Slim Grip Deburring Tool, or the DXE-22600 Deburring Tool with
Extending Handle and Extra Blades for this operation.
2. Clean the inside of the aluminum tubing to clear out any dirt or foreign material that would
cause the aluminum tubing sections to bind during assembly. Do not use any type of oil or
general lubricant between the aluminum tubing sections. Oils or general lubricants can cause
poor electrical connections for radio frequencies.
3. Clean the outside of the aluminum tubing to clear any dirt or foreign material that would cause
the clamps to malfunction during assembly.
4. The use of DXE-P8A Penetrox™A is highly recommended. Penetrox™A is an electrical joint
compound which effects a substantial electrical connection between metal parts such as
telescoping aluminum tubing or other antenna pieces. Using Penetrox™A assures high
conductivity at all voltage levels by displacing moisture and preventing corrosion or oxidation.
5. When assembling the aluminum tubing sections, ensure the area is clear of grass, dirt or other
foreign material that could cause problems during assembly of the closely fitted telescoping
sections.

- 12 -
Assemble the vertical in an area that is flat and has sufficient room for the length of the antenna
during assembly. Lay the elements out in descending OD sizes of 2", 1-3/4", 1-1/2" and 1-3/8", with
the slits in the tubes toward the top of the antenna. All the element sections are 72" long.
The bottom 2" OD element section needs no marking. On the next 1-3/4" OD element section,
measure and mark 4" from the end with no slit using a felt tip pen or “magic" marker so it will be
clearly visible. Do the same thing with the 1-1/2" OD element section. On the top 1-3/8" OD
element section, place a mark 20-1/2" from one end, and 11" from the other end.

- 13 -
Locate the hardware pack containing four element clamps. The DXE-ECL-24SS clamps are for the
bottom 2" OD element section. Slide the clamps over each element section before putting them
together. You can lightly tighten the clamps on the middle of each element section to hold them
until needed. Align the clamps on each element section facing the same direction. For final
assembly, all the clamps should be positioned close to the top of each element section and the body
of the clamp should be positioned between the slits as shown in Figure 7.
Figure 7
Using Figure 8 on the next page, start the assembly with the bottom 2" OD element section. Insert
the marked end of the 1-3/4" OD element section into the 2" OD element section until the 4 inch
mark on the 1-3/4" OD element section is even with the top of the 2" OD element section.
Position one of the larger clamps at the very end, but not hanging over. Make sure the body of the
clamp is positioned between the slots and tighten securely.
Repeat the procedure using the 1-3/4" OD element section and the marked end of the 1-1/2" OD
element section using the supplied element clamp.
Assemble the top 1-3/8" OD element section into the 1-1/2" OD element section using the same
procedure and the smaller clamp. As a double check, the length of the top element section from the
top of the previous element section should be 51-1/2 ".

- 14 -
Figure 8

- 15 -
This completes the assembly of the vertical section of the antenna. If 30 meters is your intended
band of operation, you can do final assembly because no top hat is needed for 30 meter operation.
WARNING: Attempting final assembly without proper precaution is dangerous. You
should have someone help you steady the vertical section during mating with the base
section, especially with the top-hat installed for 40 meter operation. Better yet, use a
DXE-TB-4P Tilt Base to make raising and lowering the vertical a safer, one-person task.
Mating the Vertical Sections to the Base Section
Mate the vertical section to the base tube section by sliding the bottom 2" OD element section of the
vertical over the base section tube. Slide the 2" OD element section onto the base section until there
is approximately 1" from the top of the U-clamp on the base section. Slide the clamp down to the
edge of the bottom section, between the slots, and tighten. For fine tuning, if needed, refer to the
Tuning Section of this manual.
Feedline Connections
The customer supplied coaxial cable feedline is connected to the feedline connection point on the
vertical antenna using the DXE-8X19-RT Feed Point Cable as shown in Figure 6.
If you are using the optional DXE-RADP-3 Radial Plate, DXE-8X19-RT Feed Point Cable will
connect to the Radial Plate using the optional DXE-363-SST Bulkhead Connector for a clean and
quality feedline connection. Refer to Figure 6 and Appendix A.
If you are using the optional DXE-VFCC-H05-A - 2/5 kW Vertical Feedline Current Choke
(VFCC) for Coaxially Fed 50 Ω HF Vertical Antennas, the customer supplied coaxial cable will
connect to one side of the VFCC. The supplied feedline braid will connect from the VFCC to the
antenna as shown in Appendix C.
NOTE: For operation on 40 meters, a top hat is used with the vertical section. After
building and positioning the top hat, follow the Mating the Vertical Sections to
the Base Section instructions.

- 16 -
Top Hat Assembly - 40 Meter Operation
The top hat (sometimes called a capacity hat) is used to resonate the vertical for use on 40 meters. It
will improve efficiency and provide full band coverage with a SWR below 1.2:1.
The top hat is comprised of a (patented hub, six 60 inch rods, 3 Allen head bolts, 3 regular hex bolts
and associated hardware. (US Patent No. 7,321,340).
Assemble 3 sets of Allen head hardware to the hub as shown in Figure 9. Use the holes in the hub
without the grooves. The square nuts go to the inside of the hub, with their flat side against the hub.
Screw the Allen bolts through the nuts until the threads are even with the surface of the nuts. To
prevent interference during assembly with the top section of the vertical, make sure the threads of
the Allen bolts do not extend beyond the edge of the nuts. Tighten the lock nuts slightly to hold
them in place.
Figure 9
Next, use three hex bolts, nuts, and split washers. Insert the bolts in the hub from the inside, through
the holes with grooves. Place two large flat washers on each bolt, against the hub, then a split
washer and nut.
You should have 6 tapered rods that make up the top-hat, each 60" long. The larger end of the rods
will fit in each pair of grooves on the hub, facing opposite directions and will be held in place by the
large flat washers and locking nuts.
Place the hub on a flat surface. Using one pair of rods, put the larger end in each groove, facing
opposite directions as shown and tighten the nut that is used as a locking nut. Note the position of
the rod ends under the large flat washers. Make sure the rods extend beyond the edge of the large
washers, but not beyond the flat surface of the groove. The rest of the rods are assembled in the
same way, except the rods should be staggered from top to bottom so that they do not touch each
other as they cross. As a final check, make sure the Allen bolts are not extending beyond the edge
of the square nuts inside the hub.

- 17 -
Installing the Top Hat –40 Meter Operation
Note: You need to support the vertical section to allow placement of the top hat at the top end
of the vertical with out hitting the ground. Each top hat rod is 60" long, so the top of
the vertical will need to be at least 60" off the ground to complete assembly.
The top-hat assembly attaches to the top section of the vertical using the 3 Allen head bolts. You
will need a 3/16" Allen wrench to tighten these and a 7/16" open end wrench for the lock nuts.
Install the top hat approximately 11" from the top of the antenna as shown in Figure 8. Tighten
firmly but avoid crushing or distorting the top element section.
Tuning the Vertical
The use of an antenna analyzer such as the MFJ-259 can make adjustments easier. Use the X=0 and
+/- j0 readings to determine the resonant frequency. Use a short piece of coax between the vertical
and the analyzer when making measurements. If you don’t have an analyzer, you can use the SWR
indicator of your radio or tuner.
With no top-hat, the vertical operates over the entire 30 meter band with an SWR of under 1.2:1
using the indicated section lengths. Local conditions, including proximity to structures, other
antennas, the number of radials, or personal preference may require a slight re-adjustment of the top
element section length to achieve resonance in the center of the band. Adjust the top element section
slightly longer (lower frequency) or shorter (higher frequency) as needed. With a 2:1 SWR
bandwidth in excess of 750 kHz, this vertical easily covers either band entirely and can be easily
adjusted to cover nearby MARS and CAP frequencies. No tuner is needed.
For 40 meters, adjust the top-hat hub up or down to fine-tune the center resonant frequency. Move
the hub in 1" increments at a time. You will change the resonant frequency about 10 kHz per inch of
adjustment. NO adjustment of the vertical top element section is needed.
If you are having trouble achieving resonance on either band, make sure the element section lengths
are correct and they have been properly assembled. The radial system affects the tuning as well.
Make sure you have at a minimum, 16 radials, 32 feet long, symmetrically placed around the
vertical. In-fact, a very low SWR might indicate a poor ground radial system.

- 18 -
Appendix A –Optional Radial Plate
Using an optional Radial Plate greatly simplifies mounting radial wires in a vertical installation. The
DXE-RADP-3 stainless steel patented Radial Plate contains enough stainless hardware sets to
attach 20 radials. DXE-RADW - Radial Wire Kits and Components contain everything you need to
make your own radials, including lawn staples to hold the wire down, are also available.
There are optional DX Engineering Radial Wire Kits available. DXE-RADW-500K/BD contains a
500 foot spool of 14 gauge copper stranded wire with black PVC insulation, 20 Terminal Lugs and
100 Steel or Biodegradable Lawn Staples. The DXE-RADW-1000K/BD Radial Wire Kit contains
a 1,000 foot spool of 14 gauge copper stranded wire with black PVC insulation, 40 Terminal Lugs
and 200 Steel or Biodegradable Lawn Staples. RADW-20RT, -32RT or -65RT contain 20 each
radial wires with 1/4" terminal attached. These kits come in 20 Ft, 32 Ft, or 65Ft lengths.
In order to connect a coax feedline to the vertical, you will also need an SO-239 connector to use
with the Radial Plate. This will also provide a means to ground the feedline shield to the radial
system and make a connection to the vertical. The DXE-112-KIT has the SO-239 and stainless
mounting hardware needed. You must supply a short piece of 14 gauge copper stranded wire and
lug terminal to run from the connector to the vertical as shown in Figure A-1. Stranded wire is
flexible, which works best, especially if you are using or will use a Tilt Base. You will also need a
V-Clamp, such as the DXE-SSVC-2P to secure the Radial Plate to the vertical mounting pipe.
Alternate feedpoint connections are available as shown in Appendix C.
The Radial Plate should be mounted to the vertical mounting pipe before the vertical base section. It
should be as close to the ground as possible, while still allowing access to the radial wire hardware
for tightening.
Figure A-1 - Optional DXE-RADP-3 Radial Plate shown mounted to customer supplied
mounting pipe using an optional DXE-SSVC-2P V-Clamp.
If connecting your coaxial cable direct to the Radial Plate, you can use the Optional DXE-112-KIT
SO-239, Chassis Mount Socket, Silver Plating, Teflon® Insulation. A short piece of
customer supplied feed wire would be required from the SO-239 to the antenna feedpoint
hardware.
When using the optional DXE-VFCC Vertical Feedline Choke, this bulkhead connector is
not used. Your coaxial line will connect direct to the VFCC.

- 19 -
Figure B-6: Orientation and Feed Wire
(Shown with optional Radial Plate and Tilt Base)
Appendix B –Optional Tilt Base
You may wish to add a DXE-TB-4P Tilt Base so your antenna may be quickly and easily lowered
for maintenance or severe weather. The stainless steel Tilt Base makes raising and lowering the
vertical a one-man operation.
If you are upgrading your existing DXE-40VA-1 installation, the Tilt Base will use some of the
hardware that originally came with your vertical.
Note: The optional DXE-RADP-3 Radial Plate must be placed over the mounting pipe before
installing the Tilt Base.
If you are installing the Tilt Base option on a new antenna installation, you will replace the larger
mounting plate with the smaller mounting plate included with the DXE-TB-4P.
If your vertical is already installed, you will have to disassemble it. Remove the vertical section
from the base section by loosening the bottom element clamp and lifting it off. (Be careful. Please
have some one help you). Loosen the two V-Bolt saddle clamps and remove the base section from
the mounting pipe. Remove the base tube section from the insulated channel. Remove the aluminum
backing plate from the insulated channel. You will use the 2" bolts, flat washers, spacers, split
washers and nuts. The 2" bolts must be used to attach the insulated channel to the backing plate and
subsequently, the Tilt Base plate.
Refer to the DXE-TB-4P Tilt Base manual for installation details and Tilt Base operation.
Feedline Connections When Using the Tilt Base
Connecting a feedline to the vertical when using a Radial Plate and Tilt Base can be easily done by
using the DXE-112-KIT. This kit has the SO-239 connector and stainless mounting hardware. You
must supply a 10" piece of 14 gauge copper stranded wire and a lug terminal to run from the
connector to the vertical as shown in Figure B-6. Stranded wire is flexible and works best. We
recommend crimping and soldering the wire to the wire lug. The SO-239 connection requires
soldering.
Connect the feedline pigtail from the Radial Plate to the vertical base section. Loosen and remove
the outer nut, put the star washer on first, then the pigtail wire lug, then a flat washer, then the nut.
Orient the lug so the flat side is toward the flat washer. Leave this nut loose until the antenna has
been tilted-up to the operational position. (Loosening this connection when tilting the antenna down
reduces the stress on the solder joint. Don’t forget to
re-tighten before using!) Figure B-6 shows the
correct orientation.
If you do not have a Radial Plate and you are using
the Tilt Base, connecting the feedline is a bit more
challenging. The connection to the vertical has to be
flexible to accommodate the movement encountered
during the tilt-over of the antenna. One suggested
method is to use the existing ground bracket,