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THE KL7JR 5 BAND PIPE VERTICAL 1/2 Wave on 20 Meters by John Reisenauer, Jr., KL7JR A simple, cheap and easy to build 33 feet long vertical antenna that works DX on 20 - 10 meters including WARC BANDS. That's 20,
17, 15, 12 and 10 meters!
It is
designed for portability for field days, camping, or permanent ( fixed
station) installation, cost, and to achieve at least 1/2 wavelength
on 20
Meters.
You will not
believe it's performance until you try
it!
Material List: 1 ea 10 foot 1 inch EMT conduit 1 ea 10 foot
3/4 inch EMT conduit
1 ea 10 foot
1/2 inch EMT conduit
1 ea 102 inch
CB whip
3 each hose
clamps
Assorted
bolts, nuts from junk box
Insulating
support for base of antenna (3 inch)
Assorted # 12
wire or plumbers tape for radial ring
4 to 6 or
more radials + - 16 feet long from wire for each
radial
NOTES and
BUILDING TIPS: (See drawing above)
Slide 1/2 inch EMT pipe into 3/4
inch EMT pipe 18 inches
Slide 1 inch pipe 24 inches OVER
end of 3/4 inch pipe and bolt or pin 2 places
Drill and bolt or pin above
sections together. (Assure that you have good electrical and mechanical
connections between all sections)
Hose clamp the CB whip on the
outside surface of the 1/2 inch EMT section assuring that it
overlaps 6 inches with the 1/2 EMT for a total length of all 3
sections of 33 feet top to bottom
Use some form of insulator on the
base (1 inch section) to isolate the antenna from
ground.
Build your ground and radial ring
from about 12 inches of wire and lay around the base of the
antenna.
Atttach the radials, as many as
you can lay out.
Attach the center conductor of
your coax to the base of the antenna and the shield to the ground ring
where radials are attached.
Raise antenna (See Antenna
Raiser Project) and support....you may need to guy it with rope if
windy.
Just to let you know, I put together the 5 band pipe
vertical using the cb whip antenna and it works great.
I made it 34 foot and used 13 ground radials out of #12 copper insulated wire. I use an mfj 929 tuner to tune it up. Made contacts all over Europe all the way to Japan and Argentina from New Albany, MS. 73's Jeff Staggs (K5ARE) Update From Jeff, K5ARE This is a quick way to add 80 meters to the 5 band pipe vertical that is half wave on 20 meters designed by KL7JR. I got my general license in October 2009 along with my kenwood ts-50 and a mfj 929 intellituner. I decided to make my own vertical antenna after I saw the 5 band pipe vertical on hamuniverse. I have made several dx contacts with only 100 watts with the homebrewed vertical. Tasmania, Australia; Estonia; Japan are pretty good distances to make contacts without using an amplifier. What about 80 meters? One night at work I was thinking of an 80 meter add on that I could attach to the vertical that would look decent as well as perform good. I had about 200 feet of #14 solid copper wire still on the spool that I had gotten from Lowe's. I took the spool out to the antenna and attached it to the landscape timber with a wood screw. I peeled back about 1 inch down to the bare copper wire and attached it under one of the clamps (of the vertical at it's base), making sure I had a good connection. I did not unroll the aproximately 200 feet of wire from the roll. With my fingers crossed I went inside and turned my radio to 3.862 (Mississippi Net at 6:00p.m.). My MFJ 929 tuned that frequency to a swr of 1:4. I scrolled up and down the general section of 80 meters and it tuned just fine. I may could have gotten by with a shorter run of #14 wire, but hey I was just experimenting and it worked out just fine and performs well on 80 meters. See photos below. 73's K5ARE from New Albany, MS More Projects from John:
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