Triband Quad

Model MCQ-3B for 10, 15 & 20 meters

Designed and Engineered for Superior DX, the new MCQ'S

(Mosley Cubical Quads) are rated to 1 KW AM and 2 KW

P.E.P, SSB. Maximum Front-to-Back and Forward Gain. A Single 52 ohm Line feeds the Quads via a Gamma Match resulting in a low SWR over the full bandwidth. The Square Configuration of the MCQ Series guarantees better performance by providing optimum electrical efficiency. The Durable, Lightweight, Weatherproof Aluminum Construe tion yields a lifetime of maintenance-free enjoyment.

For detailed brochure, Write Dept« 169 . FREE 1968/69 Mosley Antenna Catalog.

and receive a and receive a

Dept. 169

Bridgeton, Missouri 63042

'nc. 4610 N. Lindbergh

Dept. 169

Bridgeton, Missouri 63042

Wire Selection

A wide variety of wire types is available for construction of a thin-wire antenna. Exactly which type one should use depends upon a specific installation—the length of the antenna, the tension that will be placed on the wire, and how far one wants to go to be inconspicuous while still retaining a wire size adequate to handle the transmitter power* Insulated magnet wire, made of tinned copper, is available in sizes down to AWG #40. One should use the type with a double polyester film coating, but, even then, the smaller sizes will stretch considerably with only slight tension. So-called indoor antenna wire (Belden 8014) is the stranded equivalent of AWG #25, but has considerably better tensile strength, Bain-bach high-temperature miniature wire (75247534 series) is available in AWG 24-34 sizes and is similar to magnet wire except that it is available with a variety of colored thermoplastic films—in case one really wants to make an effort to have the antenna blend with a background color.

The smallest size in which 40% copper-weld wire is available is AWG #18 (Saxton 5300)- It is the best choice if such a size is acceptable. Piano wire is available in smaller sizes, but mav corrode in certain

environments. Its springiness also can make it difficult to handle. Clear plastic fishing line functions nicelv as a combination insulator w and tie line for the antenna ends. Summary

Thin-wire antennas can perform very well when properly installed, and can provide an antenna solution in situations where a conventional installation cannot be used. The considerations involved in using a thin-wire antenna successfully differ somewhat from those when using conventional antenna construction and this article has tried to highlight the main considerations to watcli*

In summary, a balanced form of antenna should be used, if at all possible, which is directly coupled to an antenna tuner. The antenna length should be chosen to avoid impedance extremes on harmonic operation and a high current loop at the tuner terminals oji fundamental operation. A tuner should be used which can properly couple to a balanced form of antenna—a trans -match tuner, for instance, and not a pi-network tuner. . . . W2EEY/1

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