13.3 Setting FFT Analysis Conditions
223
13
Chap
ter
13 FFT
Fun
cti
on
Total harmonic distortion (THD)
When the analysis mode is one of the following, the cursor appears and the distortion rate is calculated.
(Linear spectrum, RMS spectrum, power spectrum)
The distortion rate calculates the cursor position as the fundamental wave. When 2 cursors appear, the A
cursor becomes the fundamental wave.
When calculation results cannot be obtained, [---%] is displayed.
Note that distortion rate values may become higher depending on the window function settings.
THD
Σ
f
n
( )
2
f
0
( )
2
---------------
100
×
=
f
0
=fundamental wave
f
n
= n next higher harmonic
[%]
Summary of Contents for 8847
Page 1: ...MEMORY HiCORDER Instruction Manual 8847 December 2010 Revised edition 4 8847A981 04 10 12H ...
Page 2: ......
Page 18: ...Operating Precautions 8 ...
Page 26: ...1 4 Basic Key Operations 16 ...
Page 74: ...4 4 Waveform Observation 64 ...
Page 98: ...5 5 Managing Files 88 ...
Page 110: ...6 6 Miscellaneous Printing Functions 100 ...
Page 126: ...7 8 Seeing Block Waveforms 116 ...
Page 160: ...8 10 Making Detailed Settings for Input Modules 150 ...
Page 198: ...10 6 Numerical Calculation Type and Description 188 ...
Page 296: ...15 7 Controlling the Instrument with Command Communications LAN USB 286 ...
Page 304: ...16 2 External I O 294 ...
Page 362: ...Appendix 5 FFT Definitions A28 ...
Page 368: ...Index Index 6 ...
Page 369: ......
Page 370: ......
Page 371: ......