General exam question G9A09
Subelement G9, ANTENNAS AND FEED LINES· Group G9A
G9A09
What standing wave ratio results from connecting a 50-ohm feed line to a 200-ohm resistive load?
- A.4:1 (correct answer)
- B.1:4
- C.2:1
- D.1:2
WhyConnecting a 50-ohm feed line to a 200-ohm resistive load results in a 4:1 standing wave ratio. SWR from a resistive mismatch is the ratio of the larger impedance to the smaller, so connecting a 50-ohm line to a 200-ohm load gives 200 divided by 50, a 4:1 SWR, answer A. B, C, and D either invert the ratio or use the wrong pair of numbers, none matching this mismatch correctly.
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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