Extra exam question E9D04
Subelement E9, ANTENNAS AND TRANSMISSION LINES· Group E9D
Why should antenna loading coils have a high ratio of reactance to resistance?
- A.To swamp out harmonics
- B.To lower the radiation angle
- C.To maximize efficiency (correct answer)
- D.To minimize the Q
WhyAntenna loading coils should have a high ratio of reactance to resistance to maximize efficiency. Antenna loading coils should have a high ratio of reactance to resistance (a high Q) specifically to maximize efficiency, since a coil's resistive losses convert power to heat rather than radiating it, and a higher reactance-to-resistance ratio means less of that power is wasted as heat relative to how much reactance the coil provides, answer C. It isn't about swamping harmonics, lowering radiation angle, or minimizing Q, a low Q would actually be the opposite of what maximizes efficiency here.
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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