General exam question G4A02
Subelement G4, AMATEUR RADIO PRACTICES· Group G4A
What is the benefit of using the opposite or “reverse” sideband when receiving CW?
- A.Interference from impulse noise will be eliminated
- B.More stations can be accommodated within a given signal passband
- C.It may be possible to reduce or eliminate interference from other signals (correct answer)
- D.Accidental out-of-band operation can be prevented
WhySwitching to the opposite, or reverse, sideband when receiving CW may reduce or eliminate interference from other signals. Switching to the opposite sideband on CW shifts where an interfering signal's beat note falls relative to the desired tone, and since the interference and the desired signal move in opposite directions in pitch, picking the reverse sideband can move the interfering tone out of the audio passband or at least to a less bothersome pitch, answer C. It doesn't specifically fix impulse noise, doesn't change how many stations fit in a passband, and has nothing to do with preventing out-of-band operation.
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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