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ANTENNAS FOR 100 POUND DXPEDITIONS

12 BALCONY ANTENNAS 12.1 Problem description Not every evening will be spent in a spacious villa isolated on some island paradise. Some evenings will be spent in a small hotel room. If you’re lucky, you might have a balcony a little larger than a postage stamp from which you can deploy an antenna. This chapter will discuss some options for this situation: operating from a high balcony. There are a number of problems with such a venue. First, the balcony is likely to be very small, which limits the kinds of things that can be deployed. Secondly, any antenna we attempt to deploy will be very close to the building and very far from the ground. Finally, except perhaps for the railing on the balcony, there are few places to attach or anchor antenna pieces. I would be remiss if I didn’t mention one of the most important things about balcony antennas: safety. Dropping even a small item from a balcony on to an unsuspecting person at ground level can result in serious injury or death. Please secure all items when deploying an antenna system on a balcony. I routinely tie short lengths of Dacron rope to pieces to be sure that anything that breaks loose (or simply breaks) will not fall to the ground. Finally, the models included in these discussions will not consider the largest and most influential items in our antenna system. The building with its bricks, concrete, rebar, and stone will be ignored. Plots for far field energy distribution will therefore be absolutely bestcase. Results are likely to be much worse. These antennas do not perform well. How can they?! They are probably shortened vertical variants with poor radial systems positioned next to large building that will have detrimental affects on the pattern and overall efficiency. But, even a poor antenna radiates some signal, and some is better than none. I’ve made many contacts using a balcony antenna and had a great deal of fun doing it. 12.2 20 meters It is unlikely that you will be making 160m or 80m contacts from a balcony antenna. But, 40m, 30m, and 20m systems are possible with a minimum of fuss. This section discusses some 20m antenna ideas. 12.2.1 Fishing pole horizontal antenna As with any of these antennas, the main problem is to get the main radiator away from the building and into free space as much as possible. The three general approaches for this are to have a pole or mast extend a wire away from the building, use a mast such as that which comes with a Deluxe Buddipole system to move the antenna and feed point away from the building, or simply attach a radiator directly to the railing of the balcony. The antenna discussed here uses a small collapsible fishing pole to hold a wire.

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Antennas for 100 Pound DXpeditions - volume 1  

Computer-based antenna modeling and direct experience with lightweight portable antenna systems. Volume 1: Selected high band antennas [20-6...

Antennas for 100 Pound DXpeditions - volume 1  

Computer-based antenna modeling and direct experience with lightweight portable antenna systems. Volume 1: Selected high band antennas [20-6...

Profile for ne1rd
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