General exam question G9C02
Subelement G9, ANTENNAS AND FEED LINES· Group G9C
What is the approximate length of the driven element of a Yagi antenna?
- A.1/4 wavelength
- B.1/2 wavelength (correct answer)
- C.3/4 wavelength
- D.1 wavelength
WhyThe driven element of a Yagi antenna has an approximate length of 1/2 wavelength. A Yagi's driven element is cut to resonate near a half wavelength, the same basic length as a standalone dipole, since it's the driven element that's actually fed and needs to present a workable resonant impedance, answer B. A quarter, three-quarter, or full wavelength doesn't match the driven element's actual resonant design length, so A, C, and D are wrong.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2023-2027 NCVEC Element 3 pool (public domain); the explanation above is original writing, see our methodology.
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