HDO9000 High Definition Oscilloscopes Operator's Manual
Graphing Measurements
Measurements can be viewed in several graphical formats to facilitate your analysis:
l
Histograms
display the distribution of measured values for a given parameter as a bar chart.
l
Tracks
provide a time-correlated view of a measurement parameter compared to other
acquired channels or calculated math traces. A common usage for track is to observe the
modulation of a signal, such as amplitude, frequency, or pulse width modulation.
l
Trends
provide a view of a measurement parameter over an extended period of time and over
multiple acquisitions.
Action buttons at the bottom of the the Parameter (Px) dialogs let you quickly draw these plots for the
respective measurement.
Although these graphs plot measurement values, they are generated on the display as math functions
(F
x
) and can be set up through either the Measure or Math dialogs.
Histogramming
Histograms graphically divide data points into intervals, or bins. These bins are plotted on a bar chart
such that the bar height relates to the number of data points within each bin.
Histograms can be created to visualize the results of measurement parameters or
math functions. Regardless of the source, the histogram is created as a Histogram
function (Fx) trace, and the number of sweeps (k#) comprising the histogram is
shown on the function descriptor box. The Phistogram function creates a histogram
of a persistence display.
The range of a histogram is limited to the portion of the (measurement or math) source trace that is
visible on screen. If you zoom in on a trace, the histogram does not contain data for the no longer
visible parts of the original trace.
Thumbnail versions of measurement parameter histograms are called
. They are available
as a checkbox option on the Measure dialog. Histicons appear on the measurement parameter table,
rather than as a new math trace.
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