On an oscilloscope, which adjustable control is used to align (shift) the trace up/down or left/right so that it coincides with a chosen reference line on the graticule?
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Aposition control
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Bfocus control
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Cintensity control
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Dvolts/cm control
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Etime/cm control
Answer
Correct Answer: position control
Explanation
Introduction:Accurate oscilloscope measurements depend on correctly placing the waveform on the graticule so that amplitude and timing can be read from the scale. The control that repositions the trace without changing its scale is essential for this alignment.
Given Data / Assumptions:
- A standard oscilloscope with separate horizontal and vertical position controls.
- Graticule with labeled divisions used as reference.
- We want to align the trace with a reference line without altering scale.
Concept / Approach:The position control shifts the trace origin. Vertical position moves the baseline up or down; horizontal position shifts it left or right. This does not affect volts/div or time/div calibration—only the trace offset.
Step-by-Step Solution:Choose the desired reference line (e.g., center horizontal line).Adjust vertical position to align the baseline or a key level with that line.If needed, adjust horizontal position to center a trigger point or feature.Verify that scale settings remain unchanged.
Verification / Alternative check:Most oscilloscopes indicate the position offset on-screen (digital) or via knob detents (analog). Returning the position control to center returns the trace to its default alignment, confirming the function.
Why Other Options Are Wrong:
- Focus: Adjusts sharpness, not position.
- Intensity: Adjusts brightness.
- Volts/cm and time/cm: Change scale, not position.
Common Pitfalls:
- Misusing scale knobs when only offset is needed, thereby altering measurements.
- Forgetting separate channel position controls when multiple traces are displayed.
Final Answer:position control