Basic Qualification · B-007 Radio wave propagation · B-007-008-008
Tropospheric scatter frequently explains VHF/UHF communications well beyond the radio horizon. What makes this propagation mode possible?
- AIonized patches in the troposphere
- BIncreased daytime ionization of the D region
- CLocal cloud cover
- DSmall variations in the properties of the lower atmosphere
Correct answer: D — Small variations in the properties of the lower atmosphere. From the official ISED question bank, verified word for word.
Why
Tropospheric scatter works because small, natural variations in temperature and humidity within the lower atmosphere act like invisible mirrors that bounce VHF and UHF signals over the horizon. 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