Basic Qualification · B-003 Station assembly, practice and safety · B-003-009-002
Sur une antenne Yagi à 3 éléments, quel est l'élément rayonnant le plus long?
- ALe réflecteur
- BLe directeur
- CL'élément alimenté
- DLa perche ("boom")
Correct answer: A — Le réflecteur. Question tirée de la banque officielle d'ISDE.
Why
In a three-element Yagi antenna, the reflector is the longest radiating element because its extra length makes it resonate at a slightly lower frequency, which helps bounce radio waves forward toward the shorter director. The full explanation — and one for every question — is in Pro.
Practise this section
Station assembly, practice and safety is section B-003 of the Basic exam: Building a station safely: power supplies, grounding, RF exposure, lightning, feedline routing, and what a transmitter, receiver and transceiver actually do.
Drill B-003 — free, no account