Extra exam question E9E04
Subelement E9, ANTENNAS AND TRANSMISSION LINES· Group E9E
What is the purpose of the series capacitor in a gamma match?
- A.To provide DC isolation between the feed line and the antenna
- B.To cancel unwanted inductive reactance (correct answer)
- C.To provide a rejection notch that prevents the radiation of harmonics
- D.To transform the antenna impedance to a higher value
WhyThe series capacitor in a gamma match cancels unwanted inductive reactance. The series capacitor in a gamma match cancels the unwanted inductive reactance the gamma rod's physical arrangement introduces, letting the match present a clean, resistive impedance to the feed line, answer B. It doesn't provide DC isolation, doesn't filter or notch out harmonics, and doesn't transform impedance to a higher value on its own, the gamma rod's physical geometry, not the capacitor, is what does the impedance transformation.
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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