A Home Brew HF Vertical From Copper
Pipe
by John Reisenauer Jr.,
KL7JR/KL7USI
Use it portable or for fixed station
operation!
Interchange lengths for 5 band HF fun in the Wild!
In my younger days on portable island activating adventures, I used a
homebrew multi-banded quarter-wave vertical antenna that was easy to
assemble and disassemble and didn't take up a lot of space in my canoe.
The antenna was not only lightweight, but cheap and easy to construct,
(I didn't want to lose any more expensive ham gear the next time I'd tip
my canoe over!).
I'm still using this antenna over a decade later,
and I sure have logged a lot of DX from all over the lower 48, Alaska and
Canada with it! It's great for portable use or set it up for permanent
station operation.
BILL OF MATERIALS 1- 10' length 1/2" copper pipe (top
section)
1- 10' length 3/4 inch copper pipe (base)
1- 3/4" male sweat fitting threaded
1- 3/4" female sweat fitting threaded
1- 3/4" by 1/2" reducing coupling threaded
1- 1/2" male sweat fitting threaded
1- 1/2" female sweat fitting threaded
70' #14 or #16 wire (ground radials) and various nuts, bolts and clamps
from the junk box
Below is a simple drawing of the 20 meter
version:

CONSTRUCTION:
Now cut both pipe sections in half and solder the appropriate fittings
on. (5 foot sections makes for easy portability)
Total cost around $25.00 and two hours to build.
If you've never soldered copper tubing before, perhaps a little help
from someone who has; would be nice.
Pipe lengths plus appropriate tip = band of your choice:
PIPE
LENGTHS
TIP LENGTH BAND
3 @ 5 feet*
18
inches
14 MHz
See note
2 @ 5
feet 36
inches
18 MHz
2 @ 5
feet
12
inches
21 MHz
2 @ 5
feet
none
24 MHz
2 @ 5
feet
none
28 MHz
NOTE: * 2 @ 3/4"
and 1 @ 1/2". Use the two 3/4" sections of pipe for the other bands. )
The same ground radials were used on all bands.
I used 5 foot lengths only because it packed
well in my truck and canoe. You may want to use shorter or longer lengths
depending on your situation (ie- instead of one 5 foot length, perhaps you
want to go to a more transportable length of 2 at 30 inches long).
To secure the antenna I built an "H frame" structure from 2" PVC
pipe and used 1" PVC for the riser. The H frame breaks down to two pieces
for transporting.
You'll need to isolate the antenna from
ground. A piece of PVC pipe stuck in the ground would work too but many
islands that I want to activate back home are mostly giant rocks.
I
used a 3" long piece of scrap 1/2" PVC glued inside the T fitting of the
riser.
The antenna sits on this piece to maintain the 3" distance from
ground.
Cut a 1 inch square hole in the riser and on the bottom
section of the copper pipe (the one without a fitting on one end) to
accept the coax connection.
For a great photo of the H frame base,
see the most interesting ham website of N0LX www.n0lx.com- click in
"antennas" category for "Mini Antenna Mast and PVC base"
and in "Portable" category "Islands of Colorado" for a
heavier duty version photo).
I used heavy duty alligator clamps
for both the center coax and braid connection. Since I operate mainly on
20meters, I cut four lengths of wire at 16.5 feet long (1/4 wavelength
formula 234 divided by Freq. in MHz) out of #14 insulated wire.
Then
bare one end and tie all four together. I used a 1/4" bolt with a couple
nuts and washers as the connector.
The alligator clamp on the coax
braid clips easily on the 1/4" nut as does the clamp on the center
conductor of the coax to the pipe.
I keep the ground radials
permanently attached to the PVC H frame with ty-raps and when
transporting, I simply coil the wires and stuff in each PVC leg.
When
I'm set up, I simply throw out the radials in each direction. I put as
many in the water as I can. I'm sure it helps cut down on the "noise"
verticals are known for.
Additional
tips and notes:
I highly
recommend using a tuner with this antenna since background
and ground conditions affect SWR and will differ from set up locations and
the 24 and 28 MHz lengths are a bit long "electrically speaking".
You
may want to cut tips of the correct lengths for 10 and 12 meters.
Also, very important,
do not use a wrench to tighten
the pipe sections as it's easy to strip the pipe threads! (I only had to
do that once!). Hand tighten the copper pipe sections
only.
I can honestly admit this antenna is easy to tune on many
bands, is not noisy and works DX! 73 and happy hunting! John Reisenauer Jr., KL7JR/KL7USI