Basic Qualification · B-006 Feedlines and antenna systems · B-006-007-004
Quelle est la polarisation d'une onde électromagnétique issue d'une antenne demi-onde érigée perpendiculairement au sol?
- ACirculaire
- BHorizontale
- CElliptique
- DVerticale
Correct answer: D — Verticale. Question tirée de la banque officielle d'ISDE.
Why
When a half-wavelength antenna stands straight up, perpendicular to the ground, the electric field of the radio wave it sends out also points up and down. The full explanation — and one for every question — is in Pro.
Practise this section
Feedlines and antenna systems is section B-006 of the Basic exam: Getting the signal out: antennas, feedlines, SWR, baluns, matching, and why antenna length depends on frequency.
Drill B-006 — free, no account