Technician exam question T3A02
Subelement T3, RADIO WAVE PROPAGATION· Group T3A
How does vegetation affect UHF and microwave signals?
- A.Causes knife-edge diffraction, distorting voice peaks
- B.Absorbs signals, leading to poor reception of weak signals (correct answer)
- C.Amplifies signals, improving reception of weak signals
- D.Has no effect
WhyVegetation absorbs UHF and microwave signals, leading to poor reception of weak signals. Leaves and plant moisture absorb RF energy at UHF and microwave frequencies noticeably more than at lower frequencies, which is why foliage between two stations can significantly weaken a weak signal's reception, answer B. Knife-edge diffraction (A) is a different, usually helpful effect around solid obstructions like ridgelines, not something vegetation causes, and vegetation certainly doesn't amplify signals (C) or leave them entirely unaffected (D).
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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