Tektronix 6 series, Печатная инструкция

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Math waveform differentiation
The math capabilities of the instrument include waveform differentiation. This allows you to display a derivative math waveform
that indicates the instantaneous rate of change of the waveform acquired.
Derivative waveforms are used in the measurement of slew rate of amplifiers and in educational applications. You can create a
derivative math waveform and then use it as a source for another derivative waveform. The result is the second derivative of the
waveform that was first differentiated.
The math waveform, derived from the sampled waveform, is computed based on the following equation:
Yn = (X( n + 1) - Xn) * 1/T
Where: X is the source waveform, Y is the derivative math waveform, and T is the time between samples.
Since the resultant math waveform is a derivative waveform (see the next figure), its vertical scale is in volts/second (its
horizontal scale is in seconds). The source signal is differentiated over its entire record length; therefore, the math waveform
record length equals that of the source waveform.
Math waveform offset, position, and scale
The settings that you make for offset, scale, and position affect the math waveform you obtain. Here are some tips for obtaining a
good display:
■ Scale and position the source waveform so that it is contained on the screen. (Off-screen waveforms may be clipped,
resulting in errors in the derivative waveform).
■ Use vertical position and vertical offset to position your source waveform. The vertical position and offset will not affect your
derivative waveform unless you position the source waveform off screen so that it is clipped.
Measurement concepts
436 MSO54, MSO56, MSO58, MSO58LP, MSO64 Help