Technician exam question T9B05
Subelement T9, ANTENNAS AND FEED LINES· Group T9B
What happens as the frequency of a signal in coaxial cable is increased?
- A.The characteristic impedance decreases
- B.The loss decreases
- C.The characteristic impedance increases
- D.The loss increases (correct answer)
WhyAs the frequency of a signal in coaxial cable increases, the loss increases. As frequency increases, skin effect and dielectric losses in coaxial cable both grow, so the cable's loss per unit length increases with frequency, answer D. A coax cable's characteristic impedance is set by its physical geometry and stays essentially constant with frequency, so it doesn't rise or fall the way loss does (A, C), and loss clearly doesn't decrease with higher frequency (B), it's the opposite trend.
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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