General exam question G9A02
Subelement G9, ANTENNAS AND FEED LINES· Group G9A
What is the relationship between high standing wave ratio (SWR) and transmission line loss?
- A.There is no relationship between transmission line loss and SWR
- B.High SWR increases loss in a lossy transmission line (correct answer)
- C.High SWR makes it difficult to measure transmission line loss
- D.High SWR reduces the relative effect of transmission line loss
WhyHigh SWR increases loss in a lossy transmission line. In any real (lossy) transmission line, a high SWR means power is bouncing back and forth between the mismatched ends, and each additional trip through the line's resistive loss bleeds off more energy, so high SWR makes a lossy line's total loss worse, answer B. There is a real, well-understood relationship between the two, so A is wrong, and high SWR doesn't make loss harder to measure or somehow reduce its relative effect, if anything it does the opposite, so C and D are wrong too.
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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