Smart Average Vs. Normal Average - Fluke 199CM User's Manual Supplement

Fluke 190B/C Medical
User Manual

Smart average vs. normal average

Normal average smoothes the waveform of repetitive
signals. It gives you the averaged waveform over
successive acquisitions. A single waveform that deviates
strongly will affect the smoothed waveform. This happens
for example when looking at an interlaced video system.
The fly-back line can distort the waveform, and you will not
see it flash by as a separate waveform (See Figure 2-5).
Another characteristic of normal average is that when the
signal really changes, for example if you are probing
around, it takes some time before the new signal becomes
stable. The displayed waveform slowly changes from one
Figure 2-5. Normal Average
waveform to another waveform.
Smart average gives you the primary waveform, but
displays an incidental trace of different waveshape directly
and without affecting the primary waveform .
You can now for example look at the averaged waveform
on an interlaced video system, and still see the fly-back
line flash by (See Figure 2-6).
When the signal changes are of more permanent nature,
the averaging algorithm automatically restarts and
displays the new waveform instantly, without displaying
the distorted intermediate waveshapes.
Figure 2-6. Smart Average
2-8