Basic Qualification · B-006 Feedlines and antenna systems · B-006-009-002
Comment peut-on augmenter la directivité d'une antenne dipôle demi-onde?
- AEn y ajoutant des pièges
- BEn l'allongeant l'élément rayonnant
- CEn y ajoutant un ou des éléments parasites
- DEn utilisant un élément rayonnant de diamètre plus grand
Correct answer: C — En y ajoutant un ou des éléments parasites. Question tirée de la banque officielle d'ISDE.
Why
Adding one or more parasitic elements, which are extra metal rods that do not connect to the feedline, reshapes the signal pattern to focus energy in one direction, thereby increasing directivity. 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