Basic Qualification · B-007 Radio wave propagation · B-007-004-003
A radio transmission may follow two or more different paths during propagation, and this may result in phase differences at the receiver. What is the effect at the receiver?
- A Wavering
- B Absorption
- C Intermodulation
- D Fading
Correct answer: D — Fading. From the official ISED question bank, verified word for word.
Why
When a radio signal travels along multiple paths, the copies arrive at the receiver at slightly different times, causing them to add together or cancel each other out. 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.