Challenger DX-V111 User Manual

CHALLENGER DX-V111 ANTENNA

Congratulations on your purchase of the Challenger DX-VIII GAP Launched Antenna. You soon will enjoy
the latest in vertical antenna technology. Your GAP antenna has been designed and manufactured to
provide superior performance, and a long, trouble-free life.

The GAP technology produces highly efficient, low-Q/wide bandwidth performance. As a result, no tuning is
required in most amateur installations.

This manual is organized to minimize the amount of time necessary to assemble and install your GAP
vertical. It is recommended that you follow the instructions.

Before beginning assembly, take a few minutes to read through the site selection chapter, and to review the
safety notices.

CONTENTS
CHAPTER I: Site Considerations

Safety, nearby structures, buildings, guying, radials, feed line.

CHAPTER 2: Base Installation Putting the ground mount in place
CHAPTER 3: Assembly Space required, sub-assembly, final assembly
CHAPTER 4: Raising the Antenna Ground mounted, roof mounted
CHAPTER 5: Initial Test First operation ... a place to record VSWR data
CHAPTER 6: Tips and Troubleshooting When to call for help, if you need it
READ THE SAFETY NOTICE ON PAGE 2 BEFORE TURNING THIS PAGE
CHAPTER 1: SITE CONSIDERATIONS
1 .0 General

It is best to locate the antenna in a clear area, away from wires, metal buildings, fences and trees. As a
practical matter, many amateurs must compromise in locating their antenna. This section contains some
guidelines to assist in making those compromises.

1.1 Site Safety
A) If you have not read the safety notice, do so now. Stay away from power lines, they are life-threatening.
B) Choose an antenna site such that it is not easily accessible to people or pets. Contact with the antenna

could be dangerous. The lower tuner rods may be at high RF potential during operation. If it is not possible
to site the antenna to prevent access, then a wooden fence should be placed around the antenna, after it is
erected, to prevent contact.

1.2 Nearby Wires and Antennas

In general, any vertical antenna will exhibit mutual coupling with any other vertical structure or wire within a
few wavelengths, if the structure approaches resonance at the operating frequency. The GAP is no
exception.
Be especially careful with wires or down leads which may be within close proximity of the proposed GAP
installation site. These may include other towers, down spouts, coax from other amateur antennas, metal
pipes, or TV antenna feed lines on your property or adjoining properties.
While horizontal wires or structures may also affect performance of a nearby vertical antenna, this is much
less likely than in the case of a vertical structure.

1.3 Buildings
A) It is best to locate the antenna as far from the home as possible, to minimize interaction with house

wiring, and RFI to consumer electronics.

B) Metal-walled or roofed buildings can affect antenna operation. If you have no choice, your GAP should be
located at a corner of the building, rather than along a flat wall. In this case, the antenna should be tested
first away from the building. Section 4.2E on Elevated Mounting provides instructions for temporar y
installation and test.
C) Stucco buildings often have metal mesh in their walls, and should be treated as metal structures, until
proven otherwise.
D) Mobile homes or RVs are a special case, which will involve some individual experimentation. It is
suggested that the antenna be tested first, following the instructions in section 2.2, before attempting
installation near or on the RV.

1.4 Guying

When ground mounted, the GAP vertical is designed to withstand substantial winds without guys. Guys are
a form of insurance, however, which we recommend. Non-conductive guy rope should be fastened above
the GAP center insulator, using a stainless steel hose clamp.

Three guys should be used. Do not pull them taut; leave some slack to accommodate temperature changes.
In areas where high winds are uncommon, the guys may be dressed alongside the antenn a, and tied to guy
anchors only when needed.

Guys must be used for roof mounting. Do not rely on a chimney mount to support the GAP vertical; even
moderate winds can produce enough force to damage the mount or the chimn ey.

1.5 Radials

In choosing the site, remember that three 25' radials will be required for operation. Ideally, these would
extend straight out from the base, and be installed at 120 degree increments around the antenna. In limited
space situations, the radials may be bent or curved to fit into the available space.

1.6 Feed line

We recommend a minimum of 65' of coax cable, in order for the feed line not to look like a radial. If the site
is closer to the transmitter, make provision for coiling the coaxial cable outside the home.

CHAPTER 2: BASE INSTALLATION

2.1 Ground Mount
A) A carpenter's level, and post-hole digg er or small shovel are required for this step.
B) Referring to the parts diagram, select the 3' Mount Section.
C) At the desired installation site, dig a 3' deep hole, using the post-hole digger or small shovel. This should

be no larger than 8" in diameter.
D) Place the Mount Section in the hole, and refill with dirt to about 2' below ground level. Tamp the dirt well.
The top of the Mount Section should be 2" above ground.
E) Select the Base Section. Temporarily slide it into the Mount Section. Using the carpenter's level, make
sure that the Base Section is vertical. 'Check at least at four positions, dispersed 90 degrees around the
Base.
F) For permanent installations, a 40# bag of concrete gravel mix should be mixed according to directions
and poured in the 2' deep hole. Level the mix with the ground. Clean any re sidue from the Base Section,
above ground.
Be sure that the Base Section is vertical. Let set for 24 hours. After 24 hours, the Base Section may be
removed, for assembly in the Challenger DX-VIII antenna.
H) For temporary installations, in non-sandy soils, rocks and dirt may be packed in the hole, in lieu of
concrete. Tamp well. Soak well, and tamp again. In this case, use of guy ropes is strongly recommended.

CHAPTER 3: ASSEMBLY

3.0 General

Assembly of the Challenger DX-VIII antenna is done in stages. Sub-assemblies are completed first, then
joined in the final assembly stage. The process should take about 60 minutes, based on user experience.
Within the manual is an assembly drawing of the DX-VIII, on the back of which is a parts drawing. This
drawing is removable for use in assembly and parts identification. Partial sketches are embedded in the text
to help you visualize the assembly step referenced.

3.1 Space Required

Final assembly of the Challenger DX-VIII requires a clean, dry area approximately 35 feet long. A driveway
or rear yard would serve the purpose. Sub-assembly needs less space, a patio or deck, for exampl e.
The key to easy assembly is room to move, and a surface which allows you to recover the sheet metal
screws you drop! Rear yards are notorious for eating stainless steel screws.
A hex-head nut driver is provided with the antenna. You may find it easier to use a socket wrench to start the
sheet metal screws. Screw holes are intentionally undersized. This cold-forms the inner tubing, and results
in a more robust, electrically superior joint.

3.2 Sub-Assembly Operations

These operations are divided into three sections; ma . in, mid and lower. Referring to the removable parts
diagram, lay out all antenna parts in an orderly fashion in the assembly area.

A) Main Sub-Assembly.

1) Select the Main Section. Face the two yellow GAP leads up. Select the Top Tuner Rod and insert it into

the two stand- offs.

TOP TUNER

TOP

ROD 7'' 3"

TRANSITION

STOP SCREW

twist

BOTTOM

SCREW

MAIN

twist

2) A sheet-metal screw is used as a stop screw, to keep this rod from sliding downward. Make sure the stop
hole is above the stand-off. Insert a screw and lock washer in the stop hole, and tighten.

3) Select a yellow transition. Attach one end to the bottom of the tuner rod with screw and washer. Tighten.
Leave the other end loose.

4) Twist the two stand-offs until they face upward, as shown. Set aside.
B) Mid Sub-Assembly:

1) Select the mid section. Choose either end as the "top". it makes no difference.

2) Position the mid section so that the “top”* screw holes face up. They should remain facing up during sub-

assembly.

SECTION

COAX