- Note: Some material here is by Author: R.J.Edwards G4FGQ © 6th January 2003 For yagis or quads, the elements may be tuned and spaced to optimize gain vs. front-to-back ratio. Beams may be designed for a single band ("monobander") or, by interspersing elements for other bands, for multi-band use. Monoband beams, since they can be optimized for a single band, are generally more efficient than multibanders that usually must incorporate compromises in element size and spacing, as seen in the picture of the 5-band quad where Director-Reflector spacing is the same distance on all bands. However, a multi-band beam offers an excellent space/performance/price compromise over the multiple monobanders that would be needed to have the same spectrum coverage. Probably the most popular of the multi-band beam antennas for 20m - 10m, because of its nice combination of good multi-band performance and relatively small size and weight, is the tri-band yagi for 10m/15m/20m. This is followed closely by the multi-band 2-element quad. Both of these antennas are usually under 40 pounds in weight, relatively inexpensive, and can be readily accommodated by small rotators and modest support structures. A long-standing debate that has survived many years of discussion, research, and experimentation, is in regard to the question of whether the yagi or the quad is the better antenna for DX. The answer to this will be left for new DXers to pursue; however, one observation appears to have reached the stage of general consensus: at 35-40 ft, a 2-element quad will usually out-perform a 3-element yagi, but as height increases, the difference appears to favor the yagi. Another factor to consider is the prevailing annual weather conditions: quads may not fare as well as yagis under very icy conditions. - Special Circumstances - Hidden Antennas: Increasingly, many hams find themselves in the unfortunate situation where the usual antennas that many of us take for granted are not an option. The most common reasons are (a) codified residential restrictions; or (b) someone near-and-dear saying in a very unfriendly voice "You're going to put up what ...???". While the ARRL may be of some help with the former, you may be in a hard spot in the case of the latter! However, many hams have overcome restrictive environments by using antennas that are completely hidden from sight, or are at least very unobtrusive. A good example of the latter is an installation of a multi-band beam antenna by one of our local "Top-of-the-Honor Role" DX club members on a 50 foot tower in the midst of a very exclusive, densely populated city neighborhood. Using a low-profile wire-beam antenna (see Hex or Spider beams below) mounted on a telescoping tubular tower extending through his second-level rear deck and hidden at the base by potted plants and from neighbors by trees, he was able to effectively hide his antenna from all but those who knew to look for it. Unlike the distinctive "tower" look of the usual lattice-braced triangular construction, a tubular tower is not too different than the aluminum light poles seen in many neighborhoods, and the Hex or Spider beam configurations seem to be less noticeable than large yagis or quads. Of course, adjacent foliage and the discrete placement of decorative plants do help!Attic dipoles, verticals, or even small compact beams, can often work as well as outdoor antennas, especially in multi-level residences where attic-mounted antennas may be as high (or higher!) as their outdoor counterparts. My son lives in a covenant-restricted subdivision near Chicago, so he mounted a pair of dipoles for 20m and a 17m in his third-floor attic, using a common feedpoint. He does not use an amplifier, and our regular week-end schedule has been working well for over 5-years with this simple arrangement.
Window sill-mounted small verticals with a "ground" counterpoise consisting of a 1/4-wavelength of wire on the floor of the radio room (figure below) can be put out in the evening hours and then removed before daylight.
An antenna like this has performed very well on several mini-DXpeditions (including on a ship-board cruise) for one of our Delta DX Association club members. Other alternatives (see References) - aluminum foil-tape dipoles for 10m taped to windows, or even longer dipoles taped to the walls or ceiling; random wire antennas using thin, enameled (eg, 28 AWG wire run from a window to a tree or other convenient support - are all practically invisible, yet will allow you to enjoy some level of activity despite restrictions. SummarySo what antenna should you put up? There is really no "one fits all" answer. It depends upon many factors, but undoubtedly the most important are cost, available space, and local community regulations. From the brief discussion above, you should be able to begin looking into the best choice for your circumstances, using these very general observations:
The important thing that must be stressed is that virtually any antenna will receive and radiate signals. Just because others may have a tower and beam and you cannot is no reason for you to give up on DXing. Many DXers, at one time or another - myself included - have been faced with antenna restrictions but managed to have some fun. Indeed, DXCC has been achieved with amazingly simple stations running QRP and using hidden random wires or attic dipoles. Whatever antenna you put up, use it to develop your DXing skills of tuning, learning about propagation, understanding the characteristics of the various bands, and above all else, practice P.E.P.S.I.! So, put up whatever you can, and don't be afraid to try anything! A last word of caution: the question of "what is the best antenna" is probably the most controversial in ham radio and usually the quickest way to start a friendly argument, so be advised! ;-) What about Operating Modes - which is best for DX?
Reference Websites
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