Front-Panel Overview

To operate the time base controls

To operate the time base controls

The following exercise guides you through the time base keys, knobs, and status line.

Turn the Horizontal sweep speed (time/division) knob and notice the change it makes to the status line.

The sweep speed knob changes the sweep speed from 5 ns/div to 50 s/div for the 54620-series and 1 ns/div to 50 s/div for the 54640-series in a 1-2-5 step sequence, and the value of the sweep speed is displayed in the status line at the top of the display.

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

The Vernier softkey allows you to change the sweep speed in smaller increments with the time/div knob. These smaller increments are calibrated, which results in accurate measurements, even with the vernier turned on.

Turn the delay time knob ( ) and notice that its value is displayed in the status line.

The delay knob moves the main sweep horizontally, and it pauses at 0.00 s, mimicking a mechanical detent. At the top of the graticule is a solid triangle () symbol and an open triangle () symbol. The symbol indicates the trigger point and it moves with the Delay time knob. The symbol indicates the time reference point and is also where the zoom-in/zoom-out is referenced. If the Time Ref softkey is set to Left, the is located one graticule in from the left side of the display. If the Time Ref softkey is set to Center, the is located at the center of the display. If the Time Ref softkey is set to Right, the is located one graticule in from the right side of the display. The delay number tells you how far the time reference point is located from the trigger point .

All events displayed left of the trigger point happened before the trigger occurred, and these events are called pre-trigger information. You will find this feature very useful because you can now see the events that led up to the trigger point. Everything to the right of the trigger point is called post-trigger information. The amount of delay range (pre-trigger and post-trigger information) available depends on the sweep speed selected.

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Agilent Technologies 54621A, 24A To operate the time base controls, Press the Main/Delayed, then press the Vernier softkey