Technician exam question T3C04
Subelement T3, RADIO WAVE PROPAGATION· Group T3C
Which of the following types of propagation is most commonly associated with occasional strong signals on the 10-, 6-, and 2-meter bands from beyond the radio horizon?
- A.Backscatter
- B.Sporadic E (correct answer)
- C.D region absorption
- D.Gray-line propagation
WhySporadic E is the propagation type most commonly associated with occasional strong signals on the 10-, 6-, and 2-meter bands from beyond the radio horizon. Sporadic E is the propagation mode most commonly responsible for surprise strong openings on 10 meters, 6 meters, and occasionally 2 meters well beyond the normal radio horizon, caused by dense, patchy clouds of ionization that form unpredictably in the E region, mostly in late spring and summer, answer B. Backscatter (A) and gray-line propagation (D) are real but less commonly associated with these specific bands' occasional strong openings, and D region absorption (C) weakens signals, it doesn't produce them.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2026-2030 NCVEC Element 2 pool (public domain); the explanation above is original writing, see our methodology.
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