SignalPrep
Basic Qualification · B-007 Radio wave propagation · B-007-001-010

Reception of high frequency (HF) radio waves beyond 4000 km is generally made possible by:

  1. Ascattered wave
  2. Bspace wave
  3. Cionospheric wave
  4. Dground wave

Correct answer: C — ionospheric wave. From the official ISED question bank, verified word for word.

Why

High frequency radio waves travel thousands of kilometres by bouncing off the ionosphere, a charged layer high in the atmosphere that acts like a mirror for these signals. The full explanation — and one for every question — is in Pro.

Practise this section

Radio wave propagation is section B-007 of the Basic exam: How signals travel: the ionosphere and its layers, skip, ground wave, sporadic E, and which bands work when.

Drill B-007 — free, no account

Cette question en français · All B-007 questions