Basic Qualification · B-006 Feedlines and antenna systems · B-006-011-003
Quelle est la longueur approximative de l'élément directeur d'une antenne Yagi syntonisée à 21,1 MHz?
- A3,38 mètres
- B3,55 mètres
- C6,44 mètres
- D7,11 mètres
Correct answer: C — 6,44 mètres. Question tirée de la banque officielle d'ISDE.
Why
A Yagi antenna's director element is slightly shorter than a half-wave dipole, but the official answer key for this specific question bank lists 6.44 metres as the correct length for 21.1 MHz. 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