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Michael Coslo wrote:
Okay. Perhaps I might better characterize my experiment as a comparison of a vertical and an OCF dipole of indeterminate vertical vs horizontal performance. I was under the impression from the designers of this flavor of dipole that they were not radiating from the feedline unless you wanted that "feature". Unfortunately, even if the designers don't intend the feedline to radiate, it's very difficult to avoid. A single balun at the feedpoint is very likely not enough to prevent it. In that case you would feed the antenna with balanced line. That would make no difference at all in determining whether or not the line would radiate. Certainly the antenna doesn't seem to be radiating RF from anywhere but the antenna bits. The amount of feedline common mode current and therefore radiation will vary from band to band, probably a great deal. It's easy enough to make up a simple current probe with a clamp-on core and make quantitative measurements if you're interested. They've been described on this newsgroup several times. Roy Lewallen, W7EL |
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