Advanced Qualification · A-007 Feedlines and matching · A-007-003-008
Une antenne Yagi utilise une adaptation "gamma". La tresse de la ligne coaxiale est connectée :
- Aau condensateur variable
- Bà la tige "gamma" réglable
- Cau centre du réflecteur
- Dau centre de l'élément alimenté
Correct answer: D — au centre de l'élément alimenté. Question tirée de la banque officielle d'ISDE.
Why
In a Yagi antenna with a gamma match, the coaxial cable's outer shield (braid) connects directly to the centre of the driven element, which is the part of the antenna that actually receives or sends the radio signal. The full explanation — and one for every question — is in Pro.
Practise this section
Feedlines and matching is section A-007 of the Advanced exam: Feedlines and matching at the advanced level: transmission line theory, impedance transformation, stubs and matching networks.
Drill A-007 — free, no account