Operating Basics
6. Select Normal o
r Smart average.
Normal averaging. In the normal average mod
e, occasional deviations in a
waveform distort the averaged w ave shape, and do not show up on screen clearly.
When a signal really changes, for instance when you are probing, it takes some
time before the new wave shape is stable.
Smart averaging. Smart averaging allows you to quickly probe. Incidental
waveform changes, like a line flyback in video, show up on screen instantly.
Table 1: Comparison of averaged versus nonaveraged waveforms
Waveform with Averaging Waveform w ith no averaging
Use Persistence, Envelope,
and Dot-Join to Display
Waveforms
You can use persistence to observe dynamic signals. (See Figure 22.)
1. Open the ACQUIRE OPTIONS menu.
2. From the Waveform submenu, black-highlight Persistence... and press the
Enter button.
3. From the Digital Persistence and Display submenus, you can select the
following:
Select Short, Medium, Long,orInfinite to observe dynamic waveforms
like on an analog oscilloscope.
Select Off and Display Envelope to see the upper and lower boundaries of
dynamic waveforms (envelope mode).
Select Display Dot-join OFF to display measured samples only. Dot
join off may be useful when measuring for example modulated signals
or video signals.
Select Display Normal to turn the envelope mode off and the dot-join
function on.
36 THS3000 Series Oscilloscopes User Manual