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ANTENNAS FOR 100 POUND DXPEDITIONS •

The antenna’s visual footprint – Unless you are isolated from others, erecting large, ugly antenna systems may be frowned upon by your neighbors. You will need to select an antenna compliment that is “compatible with the neighborhood.”

The antennas discussed in this white paper conform to these guidelines to varying degrees. Evaluating the antennas is not a straightforward task either for the criteria above, or for performance in the field. Perhaps the criteria above can be used to provide guidance as to whether an antenna is eligible for this service and other criteria can determine its performance in this service. Few things get amateur radio operators more wound-up than antenna performance discussions. So, let me say this before anything else is presented: Everything in this white paper is wrong to some degree. In the sciences like physics and chemistry there is a notion of experimental error. The experiment may be intentionally flawed to take advantage of significant simplifications. Results may therefore be representative, but not numerically precise. There is also the concept of measurement error. Even when precise measurements are taken there will always be variations and precision limitations. There will be a great deal of both types of errors in what follows. If this makes you uncomfortable, stop reading now. I will be discussing antenna products and antenna designs that I have used, or considered using, on lightweight DXpeditions. I have spent the last few years gathering practical experience with these antennas and have now augmented that with computer models. These models, although they use software that has a surprising mathematical precision, are approximations of the actual antenna system. First, some antennas are described using only approximate dimensions for element lengths, element diameters, materials, or the placement of certain junctions. In some cases the imprecision is because these small differences make the model much easier to construct or because of the limitations of the modeling engine. Other justifications for this imprecision are more easy to explain: I do not own the antenna in question and have made only guesses (though well-reasoned guesses, to be sure) of some of the values. Finally, never discount the possibility that I just measured wrong, entered the data wrong, or otherwise goofed. Rather than defend every number abstractly I will discuss every choice and every method used to create the models. I’ll show the results from the modeling and compare it, where possible, to practical experience I have had with the antenna. I will also include details of the model files so everyone can execute these models and check the inputs and results for themselves. I have found this research to be helpful for my planning and my trips. I hope they will be as helpful to others.

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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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