Instrumentation Basics

Overview

Focuses on realistic measurement setups: choosing probes, understanding loading, bandwidth limits, and creating reproducible test plans for debugging and verification.

Prerequisites

• Familiarity with basic bench tools (multimeter, oscilloscope)

Learning objectives

• Select appropriate probes and instrument settings to minimise measurement error
• Understand probe loading and compensation
• Create simple, repeatable test plans and capture necessary metadata

Hands-On Mini Task

1. Compare measurements of the same high-frequency signal using a 1× passive, 10× passive, and active probe. Document differences and probe loading effects.
2. Write a one-page measurement checklist for a common verification task (e.g., measuring regulator ripple).

Expected result: clear demonstration of probe effects on measurements and a reusable checklist template.

Measurement bandwidth and aliasing

• Ensure sampling instruments (loggers, ADCs) have adequate anti‑alias filtering for the signal bandwidth being measured.

Probe compensation and verification

• Always compensate passive probes on a known calibration output; verify active probes per manufacturer guidance.

Worked example — probe loading demonstration

1. Measure a 10 MHz square wave with different probe types and note amplitude droop or ringing introduced by probe capacitance.

Troubleshooting

• If a measurement looks wrong, swap probes and verify with a second independent instrument to rule out probe artefacts.

Navigation

• Previous: Sensors and Signal Conditioning
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