Extra exam question E9C11
Subelement E9, ANTENNAS AND TRANSMISSION LINES· Group E9C
How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus soil?
- A.Radiation at low angles decreases
- B.Additional lobes appear at higher elevation angles
- C.Separate elevation lobes will combine into a single lobe
- D.Radiation at low angles increases (correct answer)
WhyMounting a vertically polarized antenna over seawater instead of soil increases radiation at low elevation angles. Mounting a vertically polarized antenna over highly conductive seawater rather than ordinary soil increases radiation at low elevation angles, since seawater's much better conductivity reduces the ground losses that otherwise suppress low-angle radiation over lossy soil, a real advantage for DX work, answer D. Low-angle radiation doesn't decrease, additional lobes don't specifically appear at higher angles because of this change, and separate lobes don't simply merge into one just from a change in ground conductivity.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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