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Hello Richard,
I think Gary and I were taking issue with your statement: "Recall that the ground wave is vertically polarized. There is no horizontally polarized wave propagation over the sea." While the first sentence is correct, the second would be a bit of surprise if it were true. Indeed, your experience on the naval vessel utilized horizontal propagation over the sea. But it is not correct to equate horizontal polarization with low-angle polarization. I think I understand what you meant to say. 73, Chuck Richard Harrison wrote: Gary, K4FMX wrote: "Are you saying that my low (less than 1/2 wavelength high) horizontal antenna will be next to useless if I live on the sea shore?" No. Your antenna will do whatever it does. I said that sea water reflects so well that the reflected ray from the sea is almost as strong as the incident ray. At low angles they cancel when horizontally polarized, being equal and of opposite polarity, and this eliminates low-angle radiation. This is demonstrated in Figs. 13 & 14 on page 3-12 of the 19th edition of the "ARRL Antenna Book". Low horizontal wires tend to send most energy straight up. This can provide near vertical incidence contacts. For distance, when the reflecting surface is good (sea water) and the antenna is low, the antenna had better be placed vertically. Results are shown in Fig 16 on page 3-13 of the same book. Best regards, Richard Harrison, KB5WZI |
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