User's Manual

Table Of Contents
6.7.2 Lines of resolution
The resolution of the spectrum increases with the number of spectral lines. The more
spectral lines, the more information the spectrum contains. Increasing the number of lines
also increases the required memory and time to measure the spectrum.
The spectrum consists of discrete spectral lines that display at fixed frequency intervals.
The height of each spectral line represents the vibration amplitude at a frequency.
Use high-resolution measurements to distinguish between two closely-spaced vibration
frequencies or when the Fmax is very large. The maximum for single-channel
measurements is 12,800 lines. The maximum for two and four channel measurements is
6,400 lines.
6.7.3 Windows
You can define windows before a spectrum is computed. A window applies a shaping
function to the waveform signal before the analyzer computes the spectrum, and helps to
prevent leakage in a spectrum. The Hanning and Uniform options are available for most
measurements. Force/Exponential is available for Impact mode.
Option Description
Hanning Smooth out end effects and reduce leakage in the spectrum. Use the
Hanning window for normal analyzer operation.
Uniform Does not apply any shaping and is subject to leakage and amplitude
errors. Use Uniform when you analyze transient signals that are
contained within the analysis time record length.
Analyze and Advanced Analyze
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