Tektronix TDS5000B Series, Онлайн руководство пользователя

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Process Overview
1 The instrument starts in the idle state; it
enters this state upon power up, upon
receiving most control setting changes, or
upon finishing acquisition tasks.
2 Control settings are implemented as they
are requested. When you toggle the
RUN/STOP control to RUN, the
instrument starts the hardware.
3 The instrument acquires samples until the
pretrigger portion of the waveform record
(channel) being acquired is filled.
4 The instrument then begins looking for a
trigger. Acquiring continues to take
place, keeping the pretrigger points
current, until triggering criteria are met or
a trigger is forced (Auto trigger mode
only). The instrument accepts the trigger.
5 The instrument acquires samples until the
posttrigger portion of the waveform
record (channel) being acquired is filled.
6 If averaging or enveloping is on, the
record becomes part of the multi-
acquisition record that these modes
produce. The process loops back to step 3
to acquire additional records until the
number of acquisitions required for the
acquisition mode currently set are
processed, and then processing continues
to step 7.
7. At this point the acquisition record is in memory and is available to the instrument for
measurement of its parameters, display, and so on.
8. The instrument then checks for a user-specified stop condition and either returns to its idle
state or continues at step 3, according to what it finds.
Keep in mind that this instrument samples in real time or random equivalent time; both sampling
systems provide pretrigger information by using the trigger to stop an already running acquisition.
Both sampling systems also sample the input after it is scaled, providing improved input
protection and dynamic range.