Oscilloscope stability — where to adjust: The front-panel controls that most directly produce a stable, non-moving waveform display are located in the ________ section.

Introduction / Context:
Achieving a stable oscilloscope display is crucial for accurate measurements. While focus, intensity, vertical scale, and timebase all matter, stability primarily depends on triggering controls that synchronize the sweep with the signal.

Given Data / Assumptions:

• Standard time-domain operation.
• Signal is repetitive or has a feature suitable for trigger.
• Scope provides trigger level, slope, mode, and source settings.

Concept / Approach:
Triggering starts each sweep at a consistent point on the waveform (e.g., rising edge crossing a set level). This alignment prevents horizontal drift and creates a steady image. Without proper trigger, even a periodic waveform appears to roll or jitter across the screen.

Step-by-Step Solution:

Verification / Alternative check:
Switch to free-run (no trigger): the waveform drifts. Re-enable proper trigger: the waveform locks in place, verifying the role of the trigger section.

Why Other Options Are Wrong:

Common Pitfalls:
Trigger level set beyond waveform peaks; triggering on the wrong source; using AC coupling that filters slow edges.

Final Answer:
trigger section