Ham Radio Antennas
Thoughts and Observations on Antennas
The challenge with antennas is that there are no definitive ways to "prove" their effectiveness for the desired result. Just too many "other" factors involved. One night I'm convinced that my home brew 1/4 wave 20m vertical is better than my 40-10 mfj -1984mp efhw sloper. Next night (or sometimes an hour later) just the reverse seems true. Then I'm surprised that my qrpguys efhw set up as an inverted vee is the best! But the sloper out does it next time! Occasionally my home brew magnetic loop shines. But next time it's hopeless! THERE IS NO FINAL ANSWER, particularly for everyone, every situation, every time of day or every propagation condition! We should share our experiences open-mindedly as just that, our experiences. None of them are 100% repeatable outside a controlled lab environment. But they are all informative. So to the new guy, get something up. Don't be discouraged. You'll never find the perfect one. All of us have put up and taken down dozens of antennas and our current "perfect" one will also be replaced.... (2019-11-14)
2020-02-02 After reading about, watching videos regarding, buying, building and modifying antennas, especially this last year or so I have some thoughts on the matter.
- My overall observation is, you're never done! There is always something you will want to do to improve the one you have or to try a new one.
- My second, observation is that there are myriad, and many apparently worth fighting over, opinions regarding antennas held by many hams! That can be frustrating. If you ask online about a certain antenna or way to deploy it, or almost anything about antennas, within the first several responses you'll get diametrically opposite opinions. And often "the most opposite" are stated most vehemently! It is almost humorous. So if you research "the online literature," brace yourself. It will be helpful but not definitive!
- Making and playing with antennas can be simultaneously fun and frustrating. It is fun because it calls upon a wide range of skills, ideas, techniques and materials. Frustrating, because seldom is the outcome as "wonderful" as you imagined or were promised! And it is all made more fun/frustrating by propagation! In the final analysis, propagation has the upper hand and on any given day can make the "worst" antenna seem the "best" only to reverse things the next day! In spite of our modern sophistication, one really doesn't know which kind of day it is until you put your baby on the air! Perhaps the moral of the story is, don't give up.
- Also high on the list of things I've learned is tools make a difference. Yes, you can open an antenna book, find a formula and cut and assemble the wires as indicated. Or you can duplicate exactly what some other guy has done. But without a few key tools, you're flying blind. Today, probably the most basic, almost essential tool, is something to measure SWR. Most modern radios provide at least some form of that. A step up is a stand-alone antenna analyzer that will not only tell you the SWR at a given frequency, but through showing the capacitive or inductive reactance gives you a clue whether your antenna is too long or too short. Another step up is the NanoVNA. It's most basic use for most hams is in plotting the SWR of an antenna across a wide frequency range. That is particularly helpful when working with multi-band resonant antennas. It's also great in showing you where your creation is currently resonant, which is often outside a ham band and hard to determine.
- Wire antennas are generally the easiest to work with and get good results. I think of them in three groups: 1) Center fed, flat top dipole types fed with either coax or open wire and supported at both ends. 2) Center fed Inverted Vees. This is a variation on the dipole but only require one support in the center. 3) End Fed antennas deployed as a sloper, flat top, inverted L or inverted vee or even as a vertical. "Random wire" and end fed half wave (EFHW) are most prominent in this group.
- Inverted vees and slopers are generally easier to mess with than dipoles or other antennas that must be supported at both ends. There are some trade offs in performance but in my experience that is a relatively small consideration.
- For me at least another almost essential thing is a collapsible fiberglass fishing pole or mast. A 20 foot collapsible fishing pole is not expensive and makes putting up an inverted vee or sloper or wire vertical made with light weight wire very easy and quick. Without that, if you have trees, you at least will need some kind of throw line and weight made of a relatively tangle free material to make the job of getting an antenna up in a tree easier. Tying a wrench or rock to paracord is a sure-fire way to increase your frustration as it twists and tangles and hangs up on weeds and branches. No matter how good you are you'll be deploying and taking down your antenna many times before you are "done" with it so anything you can do to make the setup-take-down easier and quicker, the happier you'll be.
- Resonant or non resonant / single band and multi-band. Half wave dipoles and end fed half wave antennas are in the resonant class. The so called random wire antenna and antennas like the infamous G5RV are non resonant. Generally non resonant antennas are also multi-band. Half wave center fed dipoles are by definition single band. They can be altered for multiple bands by adding traps or links or multiple elements (the fan dipole) or using an open wire feedline and a tuner. The end fed half wave antenna is unique in that if it is cut to be resonate on 40 meters, for example, it will also be resonant on all harmonically related bands higher in frequency, i.e. 20, 15, 10 and 6 meters. The "random wire" antenna's length is carefully selected to NOT be resonant on ANY ham band and can theoretically be used on any band with an antenna tuner. With a good tuner they are very versatile and reasonably effective. There are very active discussions about the pros and cons of resonant vs. non resonant antennas. In my experience it is simply a choice based on my objectives for any given antenna and situation.
- Non-wire antennas. I've had several commercial and "rigid" DIY vertical antennas. Generally I've been pleased but not overjoyed by them. All things being equal I'd go with a wire antenna. Having said that, I keep playing with them! Another interesting antenna is the small magnetic loop. I have built a couple variations of them and had some good results. I don't think I'd want one as my primary antenna but they are really fun to mess with and definitely fill a unique slot in the HF antenna world. And there are excellent yagi and similar "beam" antennas. Their performance can be excellent but the trade offs are cost and the difficulty of setting them up and maintaining them.
- Portable Antennas. This is a favorite topic for me and influences most of my thoughts on antennas. Almost any antenna can be used in a portable environment. but some are far more portable-friendly than others. Designed-for-portable rigid verticals such as the Wolf River Coils TIA antennas are clearly attractive if you can handle their collapsed size and weight. Even though they are not large nor heavy they are a bit much for an extended backpacking trip. On the other extreme is the short random wire antenna such as the end fed QRPGuys 40m-10m UnUnTenna. Using as little as 29 feet of #24 or #26 wire, or even just light weight speaker wire, one can weigh just a few ounces and is amazingly effective. They do require an antenna tuner. But it, and others like it, can be used on all hf bands and easily strung up to a tree or something. Very forgiving and versatile. I mention these two just as examples that I have worked with and perform well for me. There are many other similar ones out there. Simple wire dipoles and DIY wire verticals made with speaker wire and EFHW or trap dipoles or similar are also excellent portable antennas. If it fits your requirements for weight and size and ease of setting up, use it portable!
It's foolish to make recommendations or suggestions as to which is the "best" antenna as there is no such thing. However, if you are just starting out, for a home base primary antenna, I'd suggest serious consideration be given to either an end fed half wave (EFHW) antenna or if you have a good antenna tuner a G5RV as a baseline antenna. Both are multi-band, with limitations. Both are relatively easy to put up and both just work. Either will get you on the air. Installation wise, I think the EFHW is likely the easiest as it only requires a single support either at its far end or somewhere in the middle as an inverted vee. I really don't have any valid comment regarding their relative on-air performance. I've had hundreds of good QSOs with both.
For a portable antenna, I'd suggest a light weight EFHW, a random wire endfed, or a simple wire dipole. If weight is a real concern I'd suggest RG-174 or similar feedline, though many would argue that RG-58 or RG-8x are probably better choices if weight is not a big issue. I've used both successfully. Depending on your portable situation I'd suggest an inexpensive 15' to 20' collapsible fiberglass fishing pole and at least five small wire tent pegs and some light weight cordage to support your mast. Three of the tent pegs are for guying your pole. The other two are for the ends of an inverted vee or as spares. All of that will weigh only a pound or two and provide lots of flexibility. I also love to use small bungee cord and some cord locks to tie off my antennas. That makes getting a light weight antenna taught without having to be precise! The flexibility of the bungee cords and fiberglass mast make your antenna almost wind-proof! If weight is not a big concern for your portable operation, a free-standing portable vertical is also a very good choice.
Bottom Line. My bottom line is try something. Try many things. DIY as much as you can. Have fun! There is a special thrill from making a contact using your own antenna creation!
2018-10-14 There is no "best antenna". When someone asks, What's the best antenna? My next questions should always be for what, when, where and why? And even then there is no perfect answer. Or another way to say it is, the best antenna is the one you have and made a contact with! Most of us have no objective way to prove or really even test how well any antenna works beyond looking at its SWR and making contacts. If we do that consistently over time with several different antennas we begin to get a "feeling" for which "works" the best in the situations where we have used them.
So for example, I have had a 102 ft. G5RV up on my property in roughly the same configuration for nearly ten years. over the years I have also hung dipoles (single band, fan, trap and link versions), a vertical, G5RV Jr., end fed half waves, for periods of time at different times. The G5RV is my go-to antenna. Why? I can tune it on nearly every band from 160-6 meters. It consistently gives me good contacts under varying conditions. It is easy, especially with my auto tuner, just click and go.
All my other antennas have various advantages and limitations. Some are single band. They may out perform my G5RV on that band but for me, that trade off is not enough better to last. The vertical on my garage is also a multi band antenna and may perform better for DX at times, but is not very good for close by. And I struggle to keep the radials up even though it is on my garage roof and only needs two cut radials for each band. My multi-band dipoles, whether trap, fan or linked have limitations of bandwidth or convenience. So the G5RV is just my bread and butter, workhorse antenna in my situation here at the house.
On the other hand, I wouldn't even think of taking the G5RV out for a portable or temporary setup. It is too long and heavy and unwieldy, even for Field Day. For those occasions end fed long wires, multi-band inverted vees or verticals are my "best" antennas.
And so, I keep playing with antennas. Not particularly to find the "best one" but to learn about them, enjoy my failures and successes and marvel at making contacts on something that is clearly NOT the best antenna! For me, that is part of the joy of ham radio.
Links to my pages on various antennas: