Models LB480A/LB680A
USB Powe™
Product Manual PPA (Pulse Profiling Application)
Revision: 08/02/11
49
Poles
The
Poles
drop down allows selection of one, two or four filter poles as shown below. The default value is four poles
with option 004 and one pole without option 004.
The number of
Poles
has the effect of determining the sharpness of the frequency roll off depending on the filter
selection. The greater the number of
Poles
the steeper the roll off and again, the reduction in the high frequency
component of the signal. More
Poles
then decrease roll off but have the affect of increasing both the rise and fall times
of the displayed signal (as time relates inversely to frequency).
NOTE:
The Filter and Poles selections are only active with LB480A Option 004. Otherwise the selections will be
inactive and set to 100 kHz and one pole.
Uncalibrated Measurement Message
You will see the popup below if the measurement becomes uncalibrated due to the filter, poles or sweep time settings.
Also, an “Uncal Meas” label will appear on both the Panorama and Measurement view grids. Adjust the settings
accordingly until the error message stops.
