Basic Qualification · B-007 Radio wave propagation · B-007-008-001
Quel type de propagation inhabituelle permet d'entendre des signaux faibles en provenance de la zone de silence?
- ALa propagation par onde ionosphérique à faible angle de rayonnement
- BLa propagation troposphérique guidée (par conduit)
- CLa propagation par onde de sol
- DLa propagation par diffusion ionosphérique
Correct answer: D — La propagation par diffusion ionosphérique. Question tirée de la banque officielle d'ISDE.
Why
Scatter-mode happens when a small part of your sky-wave signal bounces off irregularities in the upper atmosphere, sending a weak, scattered signal into the skip zone where normal sky-waves do not reach. 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