Basic Qualification · B-007 Radio wave propagation · B-007-005-008
All communication frequencies throughout the spectrum are affected in varying degrees by:
- A auroras
- B meteor showers
- C the sun
- D the ionosphere
Correct answer: C — the sun. From the official ISED question bank, verified word for word.
Why
The sun drives nearly every change in radio wave behaviour because its radiation creates and alters the ionosphere, the layer of charged particles that reflects signals. The full explanation — and one for every question — is in Pro.
Practise this section
How signals travel: the ionosphere and its layers, skip, ground wave, sporadic E, and which bands work when.