Tektronix DPO2304SX, Печатная инструкция

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■ The horizontal scale determines the horizontal size of the window relative to any waveform, allowing you to scale it to
contain a waveform edge, a cycle, or several cycles.
What do you want to do next?
Learn more about Horizontal Setup.
Horizontal acquisition window interrelated parameters
Horizontal Scale, Record Length, Sample Interval, and Resolution are related parameters that specify the horizontal acquisition
window.
Because the horizontal acquisition window must fit in the 10 horizontal division display, for most cases, you can set the Time
Duration of the horizontal acquisition window (10 divs × the scale setting) as described below. By also setting a Record Length in
samples, you indirectly set the Resolution, Sample Interval, and Sample Rate for the horizontal acquisition window (waveform
record).
The relationship between these horizontal elements is as follows:
■
Time Duration (seconds) = 10 divs (window size) × Horizontal Scale (sec/div)
■ Time Duration (seconds) = Sample Interval (seconds/sample) × Record Length (samples), where Time Duration is the
horizontal acquisition window time duration, and Sample Interval (sec/sample) = Resolution (sec/sample) = 1/Sample Rate
(samples/sec)
Note that it is the Sample Interval that changes to accommodate the window Time Duration (and its scale setting) and the Record
Length setting.
The elements behave as follows:
■ If the Record Length or Time Duration change, the Sample Interval will vary to accommodate the change. The Sample
Interval can vary up to the highest Sample Rate, (this corresponds to the lowest Sample Interval, and the highest
Resolution).
■ If the Sample Interval reaches its lower limit, the Record Length must decrease if the Time Duration decreases (you set
faster scale settings), or Time Duration must increase (forcing slower scale settings) if Record Length increases (you set
longer record lengths. The equation becomes: Maximum Record Length = Time Duration ÷ Min Sample Interval.
NOTE. Resolution and the equivalent elements, Sample Interval and Sample Rate, are derived and cannot be set directly. You
can, however, check the Resolution at anytime in the resolution readout. Also note that the front-panel Resolution knob actually
adjusts the Record Length to increase sample density.
This discussion assumes that Horizontal Scale is held constant. You can hold the Sample Rate constant instead by clicking Hold
Sample Rate constant on the Record Length tab of the User Preferences control window.
What do you want to do next?
Oscilloscope reference
DPO70000SX, MSO/DPO70000DX, MSO/DPO70000C, DPO7000C, and MSO/DPO5000B Series 657