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What? You only have ONE antenna?
Copyright 2018 by Don Keith
First let me try to deflect some objections with a quartet of caveats:
--If you only operate on a single amateur band and have multiple wide-spaced elements at 120 feet for that band, then this article is probably not for you (though I believe you could benefit from having access to other radiators in addition to that one big beauty).
--If you operate several amateur bands and have multiple wide-spaced elements at 120 feet for each of those bands, you may already agree with my thought process here, if not the scale of its execution, but it wouldn't hurt you, either, to have some simpler alternatives at times.
--If you live in a condo, townhome, garden home or have to answer to covenant Nazis before you can even paint your mailbox or mow your lawn in a different direction, much less put up multiple ham radio antennas, then you probably won't be able to follow my suggestion, even if you wanted to.
--If it's all you can do to get one hank of wire in the air for whatever reason—space, money, physical ability, desire, technical knowledge, allergy to copper and aluminum—and are resolved to make do with it, then you may or may not go along with my idea here.
So here's my contention: to get the most satisfying experience from operating on the high frequency amateur radio bands, you need more than one antenna that works on the bands on which you operate—and ideally at least THREE.
Let me quickly add that I am not suggesting that you put up THIRTY antennas—three aerials for each of the ten HF bands. What I am saying is that, if possible, it is a big advantage to have a choice of antennas—and, if possible, antenna types—for each band. I'm an advocate of multi-band antennas, whether you achieve it with tuner/ladder line, traps, fan-type arrangement, or black magic. With a little ingenuity and lots of poison-ivy lotion and liniment, it's possible to have several antennas that work fine on that vast array of spectrum we have at our disposal. There are a dizzying number of sites on the Internet that give good advice on some multi-band alternatives. I even have some thoughts elsewhere on this website .
Let me give you an example of how having simple options can make a difference between euphoria and “Dang it!”
The other night, I was trying to work the 5L2 in Liberia on 20 CW. The DX cluster said he was on a certain frequency but I could not hear a thing on my big skywire loop…just the chaos of the pileup a few kilohertz above and a few dimwits calling him on his frequency. I quickly switched to my 130-foot ladder line-fed doublet. Yep, there he was, but just barely audible above the noise. But I had one more option—the 4BTV vertical out there in the backyard. Click! And he was suddenly 579 (though I, of course, gave him “599” when I worked him a few minutes later). Side benefit: on the vertical, the dimwits calling on the DX station's frequency practically disappeared.
But there is more. An hour later, I dialed back across, just to see how the 5L2 was coming in by then. He was way, way down in the crud. Jeez, propagation was gone. Glad I got him when I could. But then, on a whim, I flipped the antenna switch back to the doublet. 589! He was loud!
Now how could this be? Those of you who have been around the hobby for a while know that the layers of the upper atmosphere that reflect radio waves back to earth are constantly moving, shifting, and changing. It can offer a variety of heights with different angles of reflection (picture a basketball shot, bouncing off the backboard). Holes develop, too, allowing signals to zoom right past, through other layers who have interest in deflecting radio signals, allowing them to travel all the way out into deep space where amused aliens hear them, shake their heads, and make fun of us silly Earthlings. The angles at which our emitted signals strike those obliging layers can determine whether we bag that rare one or just waste lots of kilowatt hours trying.
And different types of antennas at different heights above ground, and varying ground systems they may be working against, can have a big influence on not only how much energy gets to the station you covet, but how much of his emitted RF energy finds its way to the front end of your receiver. Both things have to happen, you see, to make a contact!
To belabor the point, here's another recent example of success through multiple antennas. We have a Sunday night group who solve all the world's problems near the middle of the 75-meter band. Last night, the band was unusually long, and even groundwave signals from twenty miles or more away were lost in the static. One of our group was operating from an RV with a quickie antenna over on the South Carolina coast and the rest of us are in Central Alabama—about 500 miles apart. I was using the doublet, which usually does beautifully on 75, but I could copy very little of what our vacationing friend was saying.
The big loop is usually very good out to about 300 miles on 75 but mediocre any farther away (it's only 20 to 35 feet off the ground) but I decided to try it anyway. And there our RV guy was, bragging about his view of the beach from the campground, his signal suddenly well clear of the noise on the band.
Seems to me that the ideal complement of antennas—again assuming a bunch of big, honkin' beams way up in the sky is not possible—might include one multiband wire with some height above ground, some kind of wire closer to the ground so it radiates almost straight up, and a vertical. I feel rather strongly that a vertical or some kind of vertically polarized wire (inverted L, maybe) should definitely be in the mix.
Bottom line is, I think most newcomers would be surprised how often an antenna you don't think will work will actually do a better job than something far more elaborate. No matter your license class, your knowledge of things electronic, or how many kilo-dollars you have invested in your station, you have no control over the ionosphere and how it decides to treat your signal.
Yes, a lot of metal high in the air will work best most times. Too many laws of physics dictate that it is so. But it very often pays dividends to have more than one way to aim some RF at the sky and see what kind of lucky bounce you get.
Don Keith N4KC has been a ham radio operator for more than fifty years. After a long career in broadcasting and advertising, he now writes full time and has published more than thirty books, fiction and non-fiction, on a wide range of subjects including amateur radio. See www.donkeith.com or www.n4kc.com for more info.