Agilent Technologies 41A, 54621D, 24A, 42A, 54621A, 22A To capture a single event, Operating Hints

MegaZoom Concepts and Oscilloscope Operation

To capture a single event

To capture a single event

To capture a single event, you need some previous knowledge of the signal to set up the trigger level and slope. For example, if the event is derived from TTL logic, a trigger level of 2 volts should work on a rising edge. These steps show you how to use the oscilloscope to capture a single event.

1Connect a signal to the oscilloscope.

2 Set up the trigger.

a Define an edge, pulse width, pattern, or other advanced trigger type.

b Press the Mode/Coupling key and set trigger Mode to Normal.

cIf you are using the analog channels to capture the event, turn the trigger Trigger Level knob to the trigger threshold where you think the trigger should work.

3Press the Single key.

Pressing the Single key arms the trigger circuit and the Single key will be illuminated. When the trigger conditions are met, data appears on the display, representing the data points that the oscilloscope obtained with one acquisition and the Run/Stop key will be illuminated red. Pressing the Single key again re-arms the trigger circuit and erases the display.

Operating Hints

When Trigger Mode is set to Auto or AutoLvl (auto-single mode), each time Single is pressed the oscilloscope will wait for a valid trigger. If no trigger is found after about 40 ms, the oscilloscope will force a trigger, acquiring whatever signal is present. This is a handy mode to look for totally unknown situations.

When Trigger mode set to Normal, pressing Single will arm the trigger circuit and do a single acquisition when a valid trigger is seen.

You can use recalled traces to compare several single-shot events. See the "Saving and Recalling Traces and Setups" section later in this chapter.

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