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Yagi Antennas Explained

Yagi Antennas have become commonplace in amateur radio since their invention in the 1920s by Shintaro Uda and Hidetsugu Yagi. These directional antennas, consisting of two or more parallel resonant antenna elements, provide—as radio amateurs know—great performance across a variety of bands. If you've ever wanted to build and experiment with Yagi beam arrays then "Yagi Antennas Explained" is for you. The 208-page paperback is a practical guide to the design, operation, and construction of Yagi beam arrays for the amateur bands from 20m to 70cm. Rather than using mathematics, where possible, explanations are used to describe the operational aspects of beam arrays. So you'll find explanation of gain, front to back ratio, feed point impedance, polarization, radiation pattern, and bandwidth. Antennas need to be connected to the radio equipment using feeder cables; therefore, the feeder cables are reviewed, along with the techniques utilized to match a feeder cable to an antenna. Practical techniques for construction are offered in abundance, with the emphasis placed on using hand tools and materials that are generally available. Many practical designs are included, ranging from a 15m band 2-element beam, through to a 70cm band 19-element Yagi. Installations are also covered, including how performance can change as height-above-the-ground increases –and the effect of mounting several Yagi beam arrays on the same mast. The final chapter describes techniques where Yagi beam arrays can be combined to produce specialized antennas. This includes how Yagi beam arrays can be stacked or bayed. A method is described where two Yagi beam arrays can be combined to produce a dual-band antenna fed using a single feeder cable. Other examples include how two Yagi beam arrays can be combined to produce a circularly polarized beam antenna suited to use when the distant station's polarization is uncertain. If you want a practical and understandable guide to the fascinating world of building, operating, and experimenting with beam arrays from 20m to 70cm, then "Yagi Antennas Explained" is certainly the book for you.

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