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 Previous: Surfin': LED Communications over a 104-Mile Path |  Next: FCC Suspends Amateur Licenses for Failure to Maintain Mailing Address |
By Richard Arnold, AF8X
af8x@arrl.net
July 16, 2006
When you can't have a "proper" antenna due to space, antenna restrictions or other limitations (such as your spouse!), sometimes you just have to improvise. One enterprising amateur finds places for antennas in places he never even thought of, and in doing so, finds his "super antenna."
 This is the wire I use between the rig and whatever I use as an antenna. The end with the clamp attaches to the metal structure used as the antenna, such as awning framework, metal railings and flagpoles. When I am away from home, I will try anything metal to see how it tunes. I normally use an Elecraft K1 or KX1 with their internal tuners, seldom using a counterpoise with these types of antennas. |
 Sometimes I use the awning on my back patio as an antenna. The awning frame is resonant on 30 meters, but will load other bands, too. |
Antennas are probably the most discussed item of ham gear and the least understood.
For years, I have tried every conceivable type of wire antenna configuration, looking for some accident of physics that would result in a "super antenna." During this search I have discovered a few antennas that actually work pretty well, and because of my passion for portable operation, are also easily erected.
The simplest of antenna in my opinion is the half-wave end fed wire supported by a nearby tree. The half-wave wire does not require a counterpoise or ground plane to perform, as it is a complete antenna. If I feel ambitious and not in a hurry, I will often raise my full-wave wire delta loop. This needs only one overhead support and the two lower corners secured to stakes in the ground.
I like to give my friend Walt Gracey, WB8E, some good-natured harassment about his antennas when we are on one of our "lark in the park" activities. Walt usually erects a ground-mounted vertical with a large counterpoise array. This antenna takes about 30 minutes to put up -- when he has help. In the time it takes him to set up, I have already been on the air for 20 minutes.
The key factor to your choice of portable antennas depends on your type of operation. My priority is on ease of deployment and a petite package to carry. That's why I prefer wire antennas.
On the other hand, I have seen Walt erect a portable Yagi antenna that really plays, but it took two men and a strong boy to put up.
About 80 percent of my operating time is from portable locations: parks, hiking trails and yes, even my own backyard. At home, I connect the awning framework over my deck with an alligator clip attached to a short length of wire; in cooler weather I connect it to the 25 foot flagpole in my front yard, which is warmed by the southern sun. Both of these "antennas" tune to unity on the internal tuners on my Elecraft K1, as well as my KX-1.
When out in the field, I attach the wire to anything that
I think might work as an antenna. The flagpole at our local beach and the metal
railing on the boardwalk have both made decent antennas. In short, you may be
surprised at what you can load up with a tuner that will become a passable, if
not very good antenna.
 I use this flagpole at my home as an antenna -- it loads 15, 20, 30 and 40 meters. |
At home, in order to keep peace in the family, I am limited to the number of outdoor antennas. I started thinking about indoor antennas and tried the dipole in the attic, but it is difficult to scamper around in a ranch home attic -- I have the scars on my head to prove it. My next idea was a horizontal loop. My shack is a small 10×10 room with a decorative molding running around the walls near the ceiling. I stapled a 24-gauge wire on top of the molding and terminated the ends at mid-point along one wall where I attached the TV twin-lead 300 Ω feed line. The feed line is about 7 feet long and is attached to my four-band K1 with the auto tuner. My first contact on 15 meters was a station in Italy on 5 W!
Does it work? It also tunes 15, 20, 30 and 40 meters. This antenna, which Walt calls, "the nursing home loop," would work great for any one not allowed to put up outdoor antennas.
You never know -- try everything you can think of, and maybe, just maybe you will some day create that freak of nature, the small super antenna.
Dick Arnold, AF8X, of Clinton Township, Michigan, is a
retired construction electrician who has had an interest in Morse code since
studying it as a Boy Scout. When his son, Gary, W8TVR, got interested in ham
radio and built a Heathkit transmitter, Dick got involved, and due to Gary's
prodding, went from Novice to Amateur Extra in short order. He only operates
QRP CW these days, mostly from portable locations. He doesn't care about DX and
would rather have an interesting "ragchew" with any station. For
years Dick operated mobile from his motor home and later as bicycle mobile, but
more recently he's been only fixed portable. He has both the Elecraft K1 and
KX-1, which he built from kits.
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