Tektronix DPO2304SX, Printable Help

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■ When working with reference waveforms, if one or more reference waveforms are used as part of a math waveform, the
number of frames in the math waveform is the smallest of all source waveforms (reference, math, or channel waveforms).
■ If one or more reference waveforms are used in a math waveform, the record length is equal to the smallest of all the source
waveforms (reference, math, or channel waveforms). The math is calculated using the first point from each source, followed
by the next point, and so forth. This is true even if the sources have different times between points in the record.
High
The high level measurement is the value used as 100% 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 maximum value found. The histogram method uses the most common value found above
the midpoint. This value is measured over the entire waveform or gated region.
High impedance probes
Most general-purpose probes have high input impedance.
The high input resistance of passive probes (typically 10 MΩ) provides negligible DC loading and provides accurate DC
amplitude measurements.
Most passive probes require the instrument input impedance to be 1 MΩ. However, their 8 pF to 12 pF (over 60 pF for 1X)
capacitive loading can distort timing and phase measurements.
Use high resistance passive probes for measurements involving the following:
■ Device characterization (above 15 V, thermal drift applications)
■ Maximum amplitude sensitivity using 1X probe
■ Large voltage range (between 15 V and 500 V)
■ Qualitative or go/no-go measurements
High reference
The High Reference defines the high reference level of a waveform; the default level is 90%. This reference level is used with the
Low 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.
Histogram box limits - horizontal
1. Select a mode:
2. Specify the adjustment:
Oscilloscope reference
DPO70000SX, MSO/DPO70000DX, MSO/DPO70000C, DPO7000C, and MSO/DPO5000B Series 763