General exam question G3C10
Subelement G3, RADIO WAVE PROPAGATION· Group G3C
What is near vertical incidence skywave (NVIS) propagation?
- A.Propagation near the MUF
- B.Short distance MF or HF propagation at high elevation angles (correct answer)
- C.Long path HF propagation at sunrise and sunset
- D.Double hop propagation near the LUF
WhyNear vertical incidence skywave, NVIS, is short distance MF or HF propagation at high elevation angles. NVIS uses a high-angle, nearly straight-up radiation pattern to bounce signals off the ionosphere and back down at short range, useful for regional MF/HF coverage without a skip zone in the way, answer B. It isn't defined by proximity to the MUF, isn't a long-path sunrise/sunset phenomenon, and isn't a double-hop technique near the LUF, those are unrelated ideas.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2023-2027 NCVEC Element 3 pool (public domain); the explanation above is original writing, see our methodology.
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