Making Measurements

To capture glitches or narrow pulses with peak detect and infinite persistence

3 Press the Display key then press the Persist (infinite persistence) softkey.

Infinite persistence updates the display with new acquisitions but does not erase previous acquisitions. New sample points are shown at normal intensity while previous acquisitions are displayed in minimum intensity. Waveform persistence is not kept beyond the display area boundary. Any time you change a waveform setting such as sweep speed, delay time, vertical sensitivity, or offset, the previous acquisitions will be erased, then begin to accumulate again.

Use infinite persistence to measure noise and jitter, to see the worst-case extremes of varying waveforms, to look for timing violations, or to find infrequent events.

Press the Clear Display softkey to erase previously acquired points. The display will again accumulate points until Clear Display is pressed or Persist is turned off.

4Characterize the glitch with delayed sweep.

To characterize the glitch with delayed sweep, follow these steps:

Press the Main/Delayed key, then press the Delayed softkey.

To obtain a better resolution of the glitch, expand the time base.

Use the horizontal delay time knob ( )to pan through the waveform to set the expanded portion of the main sweep around the glitch.

To characterize the glitch, use the cursors or the automatic measurement capabilities of the oscilloscope.

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Agilent Technologies 41A, 54621D, 24A, 42A, 54621A, 22A manual Characterize the glitch with delayed sweep