Tektronix DPO7054, Руководство пользователя

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Pinpoint Triggers
Trigger Coupling
Trigger coupling determines what part of the signal is passed to the trigger circuit. Edge triggering can use all available
coupling types: AC, DC, Low Frequency Rejection, High Frequency Rejection, and Noise Rejection. All other trigger types
use DC coupling only. Your instrument may not offer all coupling types.
Select the trigger coupling in the Trig > A Event (Main) Trigger Setup menu. For more information, see the instrument
online help.
Horizontal Position
Horizontal position defines where the trigger occurs on the waveform record. It lets you choose how much the instrument
acquires before and after the trigger event. The part of the record that occurs before the trigger is the pretrigger part. The
part that occurs after the trigger is the posttrigger part.
Pretrigger data is valuable when troubleshooting. For example, if you are trying to find the cause of an unwanted glitch
in your test circuit, trigger on the glitch and make the pretrigger period large enough to capture data before the glitch.
By analyzing what happens before the glitch, you may uncover information that helps you find the source of the glitch.
Alternatively, to see what is happening in your system as a result of the trigger event, make the posttrigger period large
enough to capture data after the trigger.
Slope and Level
The slope control determines whether the instrument finds the trigger point on the rising or the falling edge of a signal. The
level control determines where on that edge the trigger point occurs.
Delayed Trigger System
You can trigger with the A (Main) trigger system alone or combine the A (Main) trigger with the B (Delayed) trigger to
trigger on sequential events. When using sequential triggering, the A trigger event arms the trigger system, and the B
trigger event triggers the instrument when the B trigger conditions are met. A and B triggers can (and typically do) have
separate sources. The B trigger condition is based on a time delay or a specified number of events. (See page 74,
Using A
(Main) and B (Delayed) Triggers .)
68 MSO70000/C, DPO/DSA70000B/C, DPO7000, and MSO/DPO5000 Series User Manual