General exam question G9D04
Subelement G9, ANTENNAS AND FEED LINES· Group G9D
What is the primary function of antenna traps?
- A.To enable multiband operation (correct answer)
- B.To notch spurious frequencies
- C.To provide balanced feed point impedance
- D.To prevent out-of-band operation
WhyThe primary function of antenna traps is to enable multiband operation. Antenna traps are parallel-resonant LC circuits inserted along an element that electrically isolate different sections of wire at different frequencies, letting one physical antenna present a workable resonant length on several amateur bands, which is exactly what enables multiband operation, answer A. They aren't there to notch out spurious frequencies, don't create balanced feed point impedance, and don't prevent out-of-band operation, so B, 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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