General exam question G4B12
Subelement G4, AMATEUR RADIO PRACTICES· Group G4B
What effect can strong signals from nearby transmitters have on an antenna analyzer?
- A.Desensitization which can cause intermodulation products which interfere with impedance readings
- B.Received power that interferes with SWR readings (correct answer)
- C.Generation of harmonics which interfere with frequency readings
- D.All these choices are correct
WhyStrong signals from nearby transmitters can produce received power that interferes with an antenna analyzer's SWR readings. Because an antenna analyzer's own test signal is very low power, a strong nearby transmitter's signal arriving at the antenna under test can be picked up by the analyzer and interfere with its own SWR reading, answer B. That's a matter of received power swamping a weak test signal, not desensitization-driven intermodulation or harmonic generation inside the analyzer itself, so A, C, and D overstate or misdescribe the mechanism.
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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