Keysight DSOX3012T, User Manual

Page: 269 / 530

Measurements
15
Keysight InfiniiVision 3000T X-Series Oscilloscopes User's Guide 269
The sideband used for the measurement is selected with the Channel Select
parameter. You can select the first through fifth sidebands above or below the
main range (1H through 5H above and 1L through 5L below). The full sideband
must be in the graticule to be measured. Otherwise, the measurement results will
be "Incomplete".
When this measurement is tracked with cursors, the cursors show the sideband
being measured.
Total Harmonic Distortion (THD)
Total Harmonic Distortion (THD) is the ratio of power in the fundamental frequency to
the power contained in the rest of the harmonics and noise. THD is a measure of
signal purity.
Total Harmonic Distortion (THD) measures the power contained in the bands
surrounding each harmonic and compares it to the power in the band surrounding
the fundamental frequency. The width of the bands measured is the same for the
fundamental frequency and each harmonic. That width is 1/2 of the fundamental
frequency.
Main 1H 2H 3H 4H 5H 5L 4L 3L 2L 1L
Width
Spacing