General exam question G9A11
Subelement G9, ANTENNAS AND FEED LINES· Group G9A
What is the effect of transmission line loss on SWR measured at the input to the line?
- A.Higher loss reduces SWR measured at the input to the line (correct answer)
- B.Higher loss increases SWR measured at the input to the line
- C.Higher loss increases the accuracy of SWR measured at the input to the line
- D.Transmission line loss does not affect the SWR measurement
WhyHigher transmission line loss reduces the SWR measured at the input to the line. Every trip a reflected wave makes back down a lossy line bleeds off some of its energy, so by the time it returns to the input end there's less reflected power left to combine with the forward wave, which makes the SWR measured at the input look lower than the true mismatch out at the load, answer A. Higher loss doesn't increase the input-measured SWR or improve measurement accuracy, and it clearly does affect the reading (that's the whole point of this question), 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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