Tektronix TDS5052 User Manual

Creating and Using Math Waveforms
3- 138
TDS5000 Series User Manual
Measurement scalars can be used in math expressions. For example, you can
measure the average of a waveform (using the measurement capabilities of the
instrument) and subtract it from the original waveform to define a new math
waveform. Measurements 1 through 8 are allowed in a math definition, but not
measurement functions (such as rise(Ch1)).
In FastFrame, math is applied to each frame.
Some operations that you cannot use with math waveforms are:
H Circular Math-on-Math, Measurements in Math, and Measurements on
Math: You cannot use circular definitions of math waveforms.
For example, if you define Math2 = Ch1 -- Math1, and then define a second
math waveform as Math3 = Ch2 + Math2, you cannot define a third math
waveform as Math1 = Math2 + Ch3. If you do, the Math1 definition is
rejected with an error because a circular definition is not allowed.
H Fast Acquisitions: Math is not allowed in Fast Acquisitions mode.
H Roll Mode: Math is not allowed in roll mode until you push STOP.
H Different Length Sources: If you use two waveforms (channel and reference
waveforms) of different lengths, the length of the math waveform will be the
shorter of the two lengths.
The following topics provide details about creating math waveforms.
Creating Math Waveforms. You create math waveforms when you create a math
expression. You do so by applying numerical constants, math operators and
functions to operands (see Sources on the following page). You can display and
manipulate these derived math waveforms much like you can the channel and
reference waveforms (see Operations on Math Waveforms on page 3--147).
Some examples of typical math waveforms follow:
Table 3- 11: Math expressions and t he mat h waveform s produced
To... Enter this math expression. . . and get this math waveform. . .
normalize a waveform ... shifted and scaled to fit a template
Channel 1
Source waveform
1.6V
0.8V
(Ch1 -- Meas1)/ Meas2,
where
Ch1 is the waveform shown at left
Meas1 = Low of Ch1
Meas2 = amplitude of Ch1
1.05V
1.00V
0.95V
+0.05V
0.00V
--0.05V
Normalized math waveform
Other Uses for Math
Waveforms
Using Math

Tektronix TDS5052 Specifications

General

Brand	Tektronix
Model	TDS5052
Category	Test Equipment
Language	English