Tektronix TDS5000B Series, Онлайн руководство пользователя

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Logic State Trigger Criteria
Use the Trigger When Pattern selection to determine when the instrument should trigger. Select
True to trigger the instrument when the logic patterns go true. Select False to trigger the
instrument when the logic patterns go false.
Low
The low level measurement is the value used as 0% whenever high reference, mid reference, or
low reference values are needed, such as in fall time or rise time measurements. This value can be
calculated using either the min/max or histogram method. The min/max method uses the minimum
value found. The histogram method uses the most common value found below the midpoint. This
value is measured over the entire waveform or gated region.
Low Reference
The Low Reference defines the low reference level of a waveform; the default level is 10%. This
reference level is used with the High Reference level in the calculation of rise and fall times. To
change this level, click the control and then, set the level with the multipurpose knob.
Magnitude
Inserts the text SpectralMag( ) into the math expression. Select one of the waveforms as an
argument to the function. This function creates an FFT magnitude waveform.
Maximum
This voltage measurement is the maximum amplitude. It is typically the most positive peak
voltage and is measured over the entire waveform or gated region.
Maximum Value
Inserts the text MAX( into the math expression. The MAX function accumulates over time the
maximum value at each point in the vector.
Mean
This voltage measurement is the arithmetic mean over the entire waveform or gated region.
Mean ± 1 StdDev
The percentage of points in the histogram that are within one standard deviation of the histogram
mean.
Mean ± 2 StdDev
The percentage of points in the histogram that are within two standard deviations of the histogram
mean.
Mean ± 3 StdDev
The percentage of points in the histogram that are within three standard deviations of the
histogram mean.
Median
The middle point of the histogram box. Half of all acquired points within or on the histogram box
are less than this value and half are greater than this value.