Interesting. I had not previously learned that a folded dipole could work over such a wide bandwidth. Normally, to work on other than harmonically related bands, it seems that an antenna needs to be fractal. (A log periodic is a relatively simple example of a fractal antenna.)
I wonder if the explanation is something along the lines that the folded dipole has an impedance nearer to that of fresh air, so that it serves as a relatively efficient launcher for electromagnetic waves. If that were the case, you'd expect to see the near field pattern less different from the far field pattern than for normal resonant antennas.
Correspondingly, I'd also expect there to be a lower ratio of stored energy in the antenna system to radiated energy. Then, nearby objects would have less effect on the radiation pattern, which is implied on the B2 Engineering web page. Also, RF absorption in people nearby ought to be lower, reducing the hazard that could occur to people nearby with seriously high transmitter powers
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Feeling better about it today, yet still have to correct the problem. "Fresh air", lol, I like that. On 80m it supposedly has no current to the resistor so I suppose that's perfectly true. With my winds I'm also wondering if I should put weights on the spacers... for orientation, yesterday the antenna tried to twine like a Mobius strip. Never quite made it, but if it were just a bit windier? Glad to hear from you! The other antenna is a Comet CHA250B vertical with no radials. See ya, 73. wy0mn
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What frequency range(s) is the antenna for?
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http://www.b-squareengineering.com/TerminatedFoldedDipole.htm
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I wonder if the explanation is something along the lines that the folded dipole has an impedance nearer to that of fresh air, so that it serves as a relatively efficient launcher for electromagnetic waves. If that were the case, you'd expect to see the near field pattern less different from the far field pattern than for normal resonant antennas.
Correspondingly, I'd also expect there to be a lower ratio of stored energy in the antenna system to radiated energy. Then, nearby objects would have less effect on the radiation pattern, which is implied on the B2 Engineering web page. Also, RF absorption in people nearby ought to be lower, reducing the hazard that could occur to people nearby with seriously high transmitter powers ( ... )
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"Fresh air", lol, I like that. On 80m it supposedly has no current to the resistor so I suppose that's perfectly true.
With my winds I'm also wondering if I should put weights on the spacers... for orientation, yesterday the antenna tried to twine like a Mobius strip. Never quite made it, but if it were just a bit windier?
Glad to hear from you! The other antenna is a Comet CHA250B vertical with no radials.
See ya, 73. wy0mn
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