General exam question G9B12
Subelement G9, ANTENNAS AND FEED LINES· Group G9B
G9B12
What is the approximate length for a 1/4 wave monopole antenna cut for 28.5 MHz?
- A.8 feet (correct answer)
- B.11 feet
- C.16 feet
- D.21 feet
WhyA 1/4 wave monopole antenna cut for 28.5 MHz has an approximate length of 8 feet. A quarter-wave monopole's approximate length in feet is found from 234 divided by the frequency in MHz, so 234 divided by 28.5 comes out to about 8 feet, answer A. The other values don't match applying that standard quarter-wave formula at 28.5 MHz.
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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