Extra exam question E4E09
Subelement E4, AMATEUR PRACTICES· Group E4E
What undesirable effect can occur when using a noise blanker?
- A.Received audio in the speech range might have an echo effect
- B.The audio frequency bandwidth of the received signal might be compressed
- C.Strong signals may be distorted and appear to cause spurious emissions (correct answer)
- D.FM signals can no longer be demodulated
WhyA noise blanker can distort strong signals so they appear to cause spurious emissions. An undesirable side effect of a noise blanker is that it can distort strong desired signals, momentarily gating the receiver in a way that generates its own spurious-sounding artifacts on signals that were never actually the noise it was trying to remove, answer C. It doesn't cause an echo effect, doesn't compress audio bandwidth, and doesn't prevent FM demodulation, those aren't typical noise blanker side effects.
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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