General exam question G4B10
Subelement G4, AMATEUR RADIO PRACTICES· Group G4B
Which of the following can be determined with a directional wattmeter?
- A.Standing wave ratio (correct answer)
- B.Antenna front-to-back ratio
- C.RF interference
- D.Radio wave propagation
WhyStanding wave ratio can be determined with a directional wattmeter. A directional wattmeter separates forward and reflected power on a feed line, and the ratio between those two readings is exactly what standing wave ratio is calculated from, so SWR is what it determines, answer A. It doesn't measure an antenna's front-to-back ratio, general RF interference, or propagation conditions, none of those come from a forward/reflected power reading.
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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