Using Features for Advanced Applications
TDS 684A, TDS 744A, & TDS 784A User Manual
3–169
H Read the time difference between the long vertical bars of the paired
cursors from the D: readout.
You can also use automated measurements to measure integral math waveforms.
Use the same procedure as is found under To Take Automated Measurements on
page 3–163. When using that procedure, note that your measurements on an
integral waveform will be in volt-seconds rather than in volts per second as is
indicated for the differential waveform measured in the procedure.
When creating integrated math waveforms from live channel waveforms,
consider the following topics. Note the following requirements for obtaining a
good display:
H You should scale and position the source waveform so it is contained on
screen. (Off screen waveforms may be clipped, which will result in errors in
the integral waveform).
H You can use vertical position and vertical offset to position your source
waveform. The vertical position and vertical offset will not affect your
integral waveform unless you position the source waveform off screen so it
is clipped.
H When using the vertical scale knob to scale the source waveform, note that it
also scales your integral waveform.
The source waveforms that you connect to the oscilloscope often have a DC
offset component. The oscilloscope integrates this offset along with the time
varying portions of your waveform. Even a few divisions of offset in the source
waveform may be enough to ensure that the integral waveform saturates (clips),
especially with long record lengths.
You may be able to avoid saturating your integral waveform if you choose a
shorter record length. (Press HORIZONTAL MENU ➞ Record
Length (main).) Reducing the sample rate (use the HORIZONTAL SCALE
knob) with the source channel selected might also prevent clipping. You can also
select AC coupling in the vertical menu of the source waveform or otherwise DC
filter it before applying it to the oscilloscope input.
Once you have your waveform optimally displayed, you may magnify (or
reduce) it vertically and horizontally to inspect any feature you desire. Just be
sure the integrated waveform is the selected waveform. (Press MORE, then
select the integrated waveform in the More main menu. Then use the Vertical and
Horizontal SCALE knobs to adjust the math waveform size.)
To Take Automated
Measurements
Offset, Position, and Scale
DC Offset
Using Zoom
