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However, signal noise
and the use o
can give a jagged and spiky histogram, making meaningful pe
histogram data to identify peaks from background nois
which are due to very narro
Binning and Measurement Accuracy
Histogram bins represent a sub-rang
may have a value anywhere within its sub-range. However, param
as average, assume that all events in a bin have a single value. T
bin's sub-range in all its calculations. The greater the number of bins used to subdivide a histogram's range, the
less the potential deviation between actual event values and those values assumed in histogram parameter
calculations.
Nevertheless, using more bins may require that you perform a gre
measurements, in order to populate the bins sufficiently for the identification of a characteristic histogram
distribution.
In addition, very fine grained binning will result in gaps between populated bins that may make it difficult to
determine peaks.
The oscilloscope's 20,000-parameter buffer is very effective for determining the optimal number of bins to be
used. An optimal bin number is one where the change in parameter values is insignificant, and the histogram
distribution does not have a jagged appearance. With this buffer, a histogram can be dynamically redisplayed as
the number of bins is modified by the user. In addition, depending on the number of bins selected, the change in
waveform parameter values can be seen.
WAVEFORM MEASUREMENTS
Measuring with Cursors
Cursors are important tools that aid you in measuring signal values. Cursors are markers — lines, cross-hairs, or
arrows — that you can move around the grid or the waveform itself. Use cursors to make fast, accurate
measurements and to eliminate guesswork. There are two basic types:
1. Horiz(ontal) (generally Time or Frequency) cursors are markers that you move horizontally along the
waveform. Place them at a desired location along the time axis to read the signal's amplitude at the selected
time.
2. Vert(ical) (Voltage) cursors are lines that you move vertically on the grid to measure the amplitude of a
signal.
Cursor Measurement Icons
The Readout icons depict what is being measured for each measurement mode.
Each cursor locates a point on the waveform. The cursor values can be read in the descriptor label for
the trace. Use the Position data entry fields at the right side of the dialog to place the cursors precisely.
This is the difference in Y values. The value can be read in the descriptor label for the trace.
Displays absolute and delta cursors together.
This gives the slope between cursors.
If there are non-time-domain waveforms displayed, there will also be a menu offering choices of x-axis units: s or
Hz, for exam
ple.
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the number of parameter values
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nd histogram definition artifa
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