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7/8' Side View gain reference number, while others reference an actual dipole in the same location. Thus, one who is modeling antennas over ground can get dBd numbers that vary by as much as 6 dB, due to ground gain effects and definition differences.

To simplify the electrical design, I used insulated elements spaced V4 inch above the boom. This makes the boom interaction minimal, so it isn't necessary to factor in a boom correction. Many element-mounting methods allow the boom to interact with the elements, requiring the elements to be slightly longer than predicted by computer modeling programs.

I did a bit of research on the best material for the mounting plates; Lexan seems to be the best choice. Lexan is the same stuff used for bulletproof windows, so it doesn't shatter like cheaper plastics. Unlike acrylic, it is UV resistant. UV resistance is important for anything you intend to put out in the sunshine for long periods— unless you want something that self destructs. Lexan has disadvantages: It lacks optical clarity and costs more than other plastics. I used oak blocks to attach the elements to the mounting plates, as shown in Fig 1. A V2 inch "bullet" drill makes tight fitting holes in the blocks. After pounding the tubing through the blocks, I painted the wood for weather protection. The paint also serves to glue the blocks to the tubing, though the fit was so tight that this isn't necessary.

To make field assembly easier, I decided to pin the element clamps to the boom. This requires precision drilling of the boom, lest you end up with elements that aren't in the same plane. A square boom is much easier to drill

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