Extra exam question E9E01
Subelement E9, ANTENNAS AND TRANSMISSION LINES· Group E9E
Which matching system for Yagi antennas requires the driven element to be insulated from the boom?
- A.Gamma
- B.Beta or hairpin (correct answer)
- C.Shunt-fed
- D.T-match
WhyA beta or hairpin matching system for a Yagi requires the driven element to be insulated from the boom. A beta (hairpin) matching system requires the driven element to be insulated from the boom, since the matching network relies on a specific reactance appearing right at the split, electrically isolated feed point, an arrangement a boom-grounded element wouldn't allow, answer B. Gamma, shunt-fed, and T-match systems are all specifically designed to work with a driven element that stays electrically connected to (or even mounted directly on) a grounded boom, they don't require this same insulation.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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