Tektronix CSA8000B - Manual (Page 330)

Measurement Reference Parameters and Methods
B- 68 CSA8000B & TDS8000B User Manual
Tracking Methods
This topic describes measurements methods tracking the High and Low values
used in taking automatic measurements.
The levels that the automatic measurement system derives as the High (Top) or
Low (Bottom) for a waveform influence the fidelity of amplitude and aberration
measurements. For many of the automatic measurements supported, the
instrument automatically determines these levels and disables all or some of the
High/Low tracking method controls (for example, for RMS). If the measurement
you select has High/Low methods that are appropriate to adjust (or example,
RISE time), the instrument automatically enables the method controls for your
adjustment. The methods available are shown below:
Low
High
Mid
ref
Mean Tracking Method
Hist
ogram
Mean (of Histogram) sets the values statistically. Using a histogram, it selects the mean or
average value derived using all values either above or below the midpoint (depending on
whether it is defining the high or low reference level). This setting is best for examining eye
patterns and optical signals.
Low (Min)
High (Max)
Mid ref
Min/Max Tracking Method
Min-max uses the highest and lowest values of the waveform record. This setting is best for
examining waveforms that have no large, flat portions at a common value, such as sine waves
and triangle waves -- almost any waveform except for pulses.