Extra exam question E4A06
Subelement E4, AMATEUR PRACTICES· Group E4A
What is the effect of aliasing on a digital oscilloscope when displaying a waveform?
- A.A false, jittery low-frequency version of the waveform is displayed (correct answer)
- B.The waveform DC offset will be inaccurate
- C.Calibration of the vertical scale is no longer valid
- D.Excessive blanking occurs, which prevents display of the waveform
WhyAliasing on a digital oscilloscope displays a false, jittery low-frequency version of the actual waveform. Aliasing occurs on a digital oscilloscope when the input signal's frequency is too high relative to the sampling rate, and the scope reconstructs a false, jittery, lower-frequency waveform that doesn't actually match what's really present at the input, answer A. It doesn't shift the DC offset, doesn't invalidate vertical scale calibration, and doesn't blank the display, it produces a misleading but still-displayed waveform.
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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