Tektronix 6 series, Печатная инструкция

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Scaling and positioning
The scaling and positioning controls determine the portion of the input signal received by the acquisition system. Set vertical
scaling, positioning, and DC offsets to display the features of interest on your waveform and to avoid clipping.
Each waveform Slice or Graticule contains ten major divisions. This represents the maximum digitizing range of the instrument
for any given vertical scale. Vertical waveform data that is outside (above and/or below) of the waveform Slice or Graticule is
clipped; that is, the data values exceed the digitizing capability of the ADC at the current settings. This causes inaccuracies in
amplitude-related measurements. For more information see
Vertical acquisition considerations on page 416.
Set the horizontal scale, position, and resolution (record length) to include the acquired waveform record waveform attributes of
interest with good sampling density on the waveform. These settings define the horizontal acquisition window, described in
Horizontal acquisition considerations on page 417.
NOTE. The terms vertical acquisition window and horizontal acquisition window refer to the vertical and horizontal range of the
segment of the input signal that the acquisition system acquires. The terms do not refer to any display windows on screen.
Vertical acquisition considerations
You can set the vertical scale, position, and offset of each channel independently of other channels. Vertical scale and offset
specify the vertical parameters of the waveform display for each channel. The oscilloscope only acquires signals that fall within
these parameters.
The offset control subtracts a constant DC level from the input signal before the vertical scale factor is applied, and the vertical
position control adds a constant number of divisions of signal after the scale factor is applied to the resulting difference.
The vertical scale and position controls have the following effects on the waveform display and the displayed waveform:
The vertical volts per division you set determines the vertical size of the waveform display, allowing you to scale it to contain all of
a waveform amplitude or only part.
NOTE. Amplitude-related automatic measurements (for example, peak-to-peak and RMS) will be accurate for vertical windows if
the waveform is not clipped (that is, the waveforms are acquired). But if signal amplitude were to extend outside the vertical
acquisition window, the data acquired is clipped. Clipped data causes inaccurate results if used in amplitude-related automatic
measurements. Clipping also causes inaccurate amplitude values in waveforms that are stored or exported for use in other
programs.
Waveform acquisition concepts
416 MSO54, MSO56, MSO58, MSO58LP, MSO64 Help