Extra exam question E9C13
Subelement E9, ANTENNAS AND TRANSMISSION LINES· Group E9C
How does the radiation pattern of a horizontally polarized antenna vary with increasing height above ground?
- A.The takeoff angle of the lowest elevation lobe increases
- B.The takeoff angle of the lowest elevation lobe decreases (correct answer)
- C.The horizontal beamwidth increases
- D.The horizontal beamwidth decreases
WhyAs a horizontally polarized antenna is raised higher above ground, the takeoff angle of its lowest elevation lobe decreases. As a horizontally polarized antenna is raised higher above ground, the takeoff angle of its lowest elevation lobe decreases, sending more of its radiated energy out at lower, more useful angles for long-distance HF communication, a major reason operators favor greater antenna height, answer B. The takeoff angle doesn't increase with height, and horizontal beamwidth (an azimuth-plane characteristic) isn't primarily what changes as height above ground changes.
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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