→ Proximity probes, velocity sensors, and accelerometers • Transducer selection • Transducer mounting and natural frequency • Measurement point selection • Following routes, and test planning • Common measurement errors → Signal processing • Filters: Low pass, band pass, high pass, band stop • Sampling, aliasing, dynamic range • Resolution, Fmax, data collection time • Averaging: linear, overlap, peak hold, time synchronous • Windowing and leakage