![]() That is a good model for understanding what’s happening. This is sometimes described as the antenna having a “missing half” below the surface of the ground. (Graphic from the ARRL Antenna Book, 24 th edition, courtesy of the ARRL.) The equivalent circuit of an antenna connected to a receiver (RX) showing the antenna’s radiation resistance (R r) and the ground loss resistance (R g). (See the chapter “Effects of Ground” in the ARRL Antenna Book for a complete discussion of vertical antennas, ground loss, and ground radial systems.) So, the complete circuit of the antenna begins with current at the feed point, extends through the air and soil around the antenna, and returns to the feed point. In addition, the total field from the antenna creates return currents that eventually flow back to the feed point. The same vertically polarized field causes current to flow in the soil (or whatever is below the antenna). The electric field doesn’t end at the surface of the ground. Any electrons in that field will try to move in the direction of the electric field-up and down. This means that the electric field created by the antenna is oriented vertically. Because the antenna is oriented vertically, the RF field it radiates is vertically polarized. Let’s look at the most common way to use the mesh: under the feed point of a ground-mounted vertical antenna. What’s going on? How does this work? What’s the best way to use the mesh and are there drawbacks? Vertical Antennas Make Vertical Fields Use of a “magic carpet,” as it is sometimes called, is reported to increase transmitted signal strength by an S unit or even more. Recently, the idea of rolling out metal mesh under the base of these small verticals has caught on. These antennas are relatively small, don’t require high supports, and are easy to set up, but their performance can be disappointing. Loaded horizontal dipoles on a tripod and small transmitting loops are also common. Verticals, especially base- and center-loaded models, are very popular, for example. Everything else is just wire and rope and 3 stakes all of which fits in a large ZipLock bag.ĭoes it work? When I set everything up for 20m in my backyard, I got through to a station from Venezuala on the second call QRP from suburban Maryland and got a 59 even after telling him my setup.Operating portable is always a challenge, particularly with HF antennas that are usually close to the ground and quite a bit smaller than a full quarter- or half-wave. These are supported at the ends by 2' fiberglass rods (former 4' driveway markers, up for the trip, the whip sides into the hollow center of the mast and the 4 2' rods are strapped to that making a nice compact bundle. I used the radial connectors to connect 4 elevated radials to the sides of the VersaTee, two off each side. For the radiator, I used the MFJ 17' telescoping whip, which is full sized for 20m (and of course on 10, 12 and 15 by retracting some of it). I didn't need the coils or the tripod, so I saved a ton of money versus the deluxe package. So, using the information in the book, I bought the 8' mast, the VersaTee, the Coax and the radial connectors. Each section ends with a "cookbook" show the best recipe for each band.įor my needs, I wanted to operate portable (SOTA) on 10m, 15m & 20m. This guy took the Buddipole system through about every conceivable configuration and measured the results. I really encourage you to download and read the free book Buddipole in the Field by NE1RD. So really before answering the question of which one to buy, you have to identify how you are going to use it and what bands you plan to work. ![]() With any of the three main Buddipole packages, you have the parts to make a number of types of antennas: vertical, dipole, even a yagi (with a few extra parts) on any of the ham bands (except 160m). ![]() With a more typical product, you have, say, a portable 10m dipole, period. All the pieces are made light for portability and the sizes are such that you can construct a variety of effective antennas based on your situation. The real heart of the system is the VersaTee and the fact that all the parts for all the products use the same size threaded connector. It's based around being able to create an effective antenna that is both portable and has flexibility for configuration. Buddipole is really a system rather than a product per say.
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