Tektronix TDS7254 Stereo System User Manual


 
Creating and Using Math Waveforms
CSA7000 Series, TDS7000 Series, & TDS6000 Series Instruments User Manual
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Sources. Math Waveforms can incorporate the following sources:
H Channel waveforms
H Reference waveforms
H Measurements (automated measurements) that measure channel, reference,
histogram, or math waveforms
H Math waveforms
Source Dependencies. Math waveforms that include sources as operands are
affected by updates to those sources:
H Shifts in amplitude or DC level of input sources that cause the source to clip
also clips the waveform data supplied to the math waveform.
H Changes to the vertical offset setting for a channel source that clips its data
also clips the waveform data supplied to the math waveform.
H Changes to the acquisition mode globally affects all input channel sources,
thereby modifying any math waveforms using them. For example, with the
acquisition mode set to Envelope, a Ch1 + Ch2 math waveform will receive
enveloped channel 1 and channel 2 data and, therefore, will also be an
envelope waveform.
H Clearing the data in a waveform source causes a baseline (ground) to be
delivered to any math waveform that includes that source until the source
receives new data.
Expression Syntax. You build math waveforms using the Define/Edit Expression
control window. To help you create valid math waveforms, this window blocks
most illegal entries by disabling any window element that would create an
invalid entry in the math waveform expression.