Technician exam question T9B09
Subelement T9, ANTENNAS AND FEED LINES· Group T9B
T9B09
What can cause erratic changes in SWR?
- A.Local thunderstorm
- B.Loose connection in the antenna or feed line (correct answer)
- C.Over-modulation
- D.Overload from a strong local station
WhyA loose connection in the antenna or feed line can cause erratic changes in SWR. A loose connection at the antenna or somewhere along the feed line makes intermittent, unstable contact, which shows up as SWR readings that jump around erratically rather than staying steady, answer B. A thunderstorm (A), over-modulation (C), and overload from a strong nearby station (D) don't produce that kind of mechanical intermittency in an SWR reading.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2026-2030 NCVEC Element 2 pool (public domain); the explanation above is original writing, see our methodology.
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