Technician exam question T9B04
Subelement T9, ANTENNAS AND FEED LINES· Group T9B
What is the major function of an antenna tuner (antenna coupler)?
- A.It matches the antenna system impedance to the transceiver's output impedance (correct answer)
- B.It helps a receiver automatically tune in weak stations
- C.It allows an antenna to be used on both transmit and receive
- D.It automatically selects the proper antenna for the frequency band being used
WhyAn antenna tuner's major function is matching the antenna system impedance to the transceiver's output impedance. An antenna tuner's job is to match the impedance the antenna system presents at the shack end of the feed line to the impedance the transceiver's output stage expects, letting the transmitter operate efficiently even into a less-than-ideal load, answer A. It doesn't help a receiver find weak signals (B), it doesn't let one antenna serve transmit and receive, most antennas already do that without a tuner (C), and it doesn't automatically switch between different antennas (D).
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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