User Manual

3.9 Analysis with the Waveform Screen
80
A starting point for FFT analysis can be specified on an existing memory wave-
form before analyzing.
The procedure depends on the Trigger Mode setting.
See "Trigger Modes and Averaging" (⇒ p. 60)
• When the Trigger Mode is [Single]
Analysis is performed once on the specified number of analysis points begin-
ning with the specified starting point, and analysis results are displayed.
This is convenient for analyzing only a specific range. However, if averaging is
enabled, analysis repeats for the specified averaging count.
• When the Trigger Mode is [Auto] or [Repeat]
Analysis is performed repeatedly on the specified number of analysis points
beginning with the specified starting point and ending with end of waveform
data, and final analysis results are displayed (because analysis is only per-
formed on the specified number of analysis points, final analysis results may
be determined and become available before the end of the waveform data).
The starting point can be specified by one of the following methods:
(1) Verifying the analysis starting point while viewing analysis data
(⇒ p. 81)
The memory waveform and analysis results are displayed at the same time on
the Waveform screen (Sheet Settings screen: Display type [Wave+FFT] or
[Wave+Nyquist]) and the analysis starting point is specified on the memory
waveform.
(2) Performing FFT analysis after specifying a starting point on an existing
memory waveform using the A/B cursors (⇒ p. 83)
The analysis starting point is specified using the A/B cursors with the Memory
function. If the cursors are not displayed, analysis begins at the start of the data.
The starting position cannot be verified while the FFT function is enabled.
3.9.3 Analyzing after Specifying an Analysis Starting
Point