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In ether case adding that much wire (15,840 feet) for so little gain
sure doesn't seem worthwhile. 73 Danny, K6MHE ======================== Danny, I quite agree. The current-carrying cross-sectional area of the Earth is enormous at distances from the antenna base of 1/4-wavelength and greater. Regardless even of very poor soil resistivity, loss in the soil is sensibly zero. Furthermore, propagation velocity in the soil is MUCH less than the free space velocity and I am of the opinion that computer models give a very distorted picture of what actually happens. At distances of the order of 1/8 free-space wavelength practically all of the current flows in the soil. Shallow-buried radials might just as well not be there. The copper is better used to increase the number of short radials. But an increase in the number of short radials is a waste of copper anyway when the number of radials is already very large. What B,L&E were doing with 120 radials at MF in 1937 is hardly relevant. I understand they forgot to determine ground conductivity - an indication they didn't fully appreciate what they were about. As they were the first in the field to make such measurements this omission is understandable. But at HF, soil characteristics are considerably different - factors which computer model users do not feed into their models. Computerised antenna model users are inclined to suffer from delusions of accuracy - drowning, unaware, in a sea of uncertainties. But there's no real harm done! ;o) ---- Reg. |
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