40 METER CAGE DIPOLE
A few summers back I put up a Half Wave Cage Dipole 40 Meter Antenna.
is constructed and marketed by W4HV in Mt. Carmel, Tn. and available
for any band. He advertises on the internet.
The Antenna consists
of 6 runs of #14 stranded wires spaced evenly
around (8) 12" Diameter plastic Hula Hoop spacers made of 3/4"
Poly Tubing. The Poly is joined
using a small wooden dowel and Glue. You can make the Hoops 12"
15" 20" it is not critical. Drill the 6 holes and space evenly
around the circumference.
Tip: When putting this together, bunch all 4 hoops together, near the
feedpoint and feed your wires thru each hoop one wire at a time until
all are thru and connected to the common point on the choke. Secure
with a split bolt. Slide each hoop into position. Secure the
wires at the distant end with a split bolt. Be sure to attach a
single 5' wire.
Use PVC and caps for the end insulator and drill large 1/2"
holes. Run the tuning stub
along the support rope and ty-rap.
At the Feed point is a RG-8X Current Choke to prevent RF coming back on
The Current Choke is
made using 22' of RG-8X Coaxial cable wrapped around a 2" Diameter of
PVC. Use a Tee on top and cap all open ends. A SO-239
can be mounted at the bottom with a weep hole. The Tee also has
caps. Drill 1/2 holes for the wires to go thru. Bring
out the split coax to secure to each side of the dipole.
Split Bolts are used to secure all the wires at the ends and the feed
point. No soldering.
The antenna has the advantage of being broad banded. It covers the
entire 40 meter
band with a SWR of less than 1.7 : 1 and a best frequency of 1.1 : 1 at
Also, the efficiency is greater than a single wire dipole due to the
six wire current distribution.
My antenna is hung off the side of my 40 foot tower as a sloping
dipole. It can be installed in about any attitude.
Horizontal, Vertical, Slope, Inverted V etc.
A short 5 ft run of wire at the ends is used to fine tune the antenna
the middle of the band. I tie-wrapped the wire to my support rope.
You can build your own or buy from W4HV at his website. With the
price of copper, you will have about the same money invested either way!
It has been a real performer for me!
40 Meter Cage Dipole Up 40 feet
RG-8X Current Balun At The Feed