Which instrument is used to detect noise, distortion, and glitches in a signal?

• A. Oscilloscope
• B. Logic Analyzer
• C. Spectrum Analyzer
• D. Multimeter

Answer: (A)

An oscilloscope is the tool that best reveals noise, distortion, and glitches because it shows voltage as it changes over time. This time-domain view lets you see the actual waveform shape, so you can spot tiny irregularities, random jitter, and sudden spikes that indicate noise or a temporary glitch. You can also use triggering to freeze a transient and inspect its exact form, which helps distinguish a real distortion pattern from normal signal variation.

Other instruments focus on different aspects. A logic analyzer collects and analyzes digital signals and their timing relationships, not the continuous analog waveform. A spectrum analyzer displays frequency content and the noise floor in the frequency domain, which is excellent for understanding what frequencies are present but it hides when those issues occur in time. A multimeter provides static measurements of basic electrical values and isn’t suited to observe transient events or fast waveform changes. So for detecting noise, distortion, and glitches in a signal, the oscilloscope is the most suitable choice.