Extra exam question E9C07
Subelement E9, ANTENNAS AND TRANSMISSION LINES· Group E9C
What is the approximate feed point impedance at the center of a two-wire half-wave folded dipole antenna?
- A.300 ohms (correct answer)
- B.72 ohms
- C.50 ohms
- D.450 ohms
WhyA two-wire half-wave folded dipole antenna has an approximate feed point impedance of 300 ohms at its center. A two-wire half-wave folded dipole's feed point impedance at its center is approximately 300 ohms, about four times an ordinary half-wave dipole's roughly 72 ohms, the well-known step-up effect of the folded-dipole configuration, answer A. 72, 50, and 450 ohms don't match this standard folded dipole figure.
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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