General exam question G9B01
Subelement G9, ANTENNAS AND FEED LINES· Group G9B
What is a characteristic of a random-wire HF antenna connected directly to the transmitter?
- A.It must be longer than 1 wavelength
- B.Station equipment may carry significant RF current (correct answer)
- C.It produces only vertically polarized radiation
- D.It is more effective on the lower HF bands than on the higher bands
WhyStation equipment may carry significant RF current when a random-wire HF antenna is connected directly to the transmitter. A random-wire antenna fed directly at the transmitter, without a proper counterpoise or balanced feed, relies on the station equipment and its grounding to serve as part of the antenna system's return path, which means significant RF current can flow on the equipment chassis and cabling, answer B. It doesn't need to be longer than a full wavelength, its polarization isn't restricted to purely vertical, and it isn't inherently better on the lower HF bands than higher ones, so A, 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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