Extra exam question E8D07
Subelement E8, SIGNALS AND EMISSIONS· Group E8D
What is a common cause of overmodulation of AFSK signals?
- A.Excessive numbers of retries
- B.Excessive frequency deviation
- C.Bit errors in the modem
- D.Excessive transmit audio levels (correct answer)
WhyA common cause of overmodulation of AFSK signals is excessive transmit audio levels. A common cause of overmodulation in AFSK signals is simply feeding the transmitter excessive transmit audio levels, driving the modulator harder than it's designed to handle and generating distortion products beyond the signal's intended bandwidth, answer D. Excessive retries, excessive frequency deviation as a cause in itself, and modem bit errors are downstream symptoms or unrelated issues, not the direct root cause of overmodulation from audio drive level.
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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