Extra exam question E8C12
Subelement E8, SIGNALS AND EMISSIONS· Group E8C
What factors affect the bandwidth of a transmitted CW signal?
- A.IF bandwidth and Q
- B.Modulation index and output power
- C.Keying speed and shape factor (rise and fall time) (correct answer)
- D.All these choices are correct
WhyA transmitted CW signal's bandwidth is affected by keying speed and shape factor, rise and fall time. A transmitted CW signal's bandwidth is shaped by both keying speed (faster sending spreads more energy) and the shape factor of the keying waveform, how quickly the signal rises and falls with each dit and dah, sharper transitions spreading more bandwidth via key clicks, answer C. IF bandwidth and Q describe receiver characteristics rather than the transmitted signal's own bandwidth, and modulation index and output power don't determine a CW signal's bandwidth either.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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