General exam question G4A07
Subelement G4, AMATEUR RADIO PRACTICES· Group G4A
What happens as a receiver’s noise reduction control level is increased?
- A.Received signals may become distorted (correct answer)
- B.Received frequency may become unstable
- C.CW signals may become severely attenuated
- D.Received frequency may shift several kHz
WhyReceived signals may become distorted as a receiver's noise reduction control level is increased. DSP noise reduction works by algorithmically suppressing content that doesn't fit the pattern of a normal voice or CW signal, and pushed too far that same processing starts stripping wanted signal detail too, so received audio may become distorted, answer A. It's a receive-audio process, so it has no effect on the transmitter's frequency stability or on shifting the received frequency.
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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