Basic Qualification · B-006 Feedlines and antenna systems · B-006-011-011
Si le gain d'une antenne Yagi à six éléments est d'environ 10 dBi, quel serait le gain global de deux de ces antennes si elles étaient jumelées ("stacked")?
- A13 dBi
- B7 dBi
- C20 dBi
- D10 dBi
Correct answer: A — 13 dBi. Question tirée de la banque officielle d'ISDE.
Why
Stacking two identical antennas doubles the effective power in the desired direction, which adds exactly 3 decibels to the gain. 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