Tektronix CSA8000B Manuel d'utilisateur télécharger pdf (Page 115)

Triggering

CSA8000B & TDS8000B User Manual

3-41

Positive-going edge Negative-going edge

Trigger slope can be positive or negative, with

trigger point occurring on the slope specified.

Trigger level

can be adjusted

vertically.

Figure 3- 11: Slope and level define the trigger event

Trigger Modes. The trigger modes control the behavior of the instrument when

not triggered:

H Normal mode sets the instrument to acquire a waveform only when

triggered. Normal mode does not acquire data if triggering stops, rather the

last waveform records acquired remains “frozen” on the display (if the

channels containing them are displayed). If no last waveform exists, none is

displayed. See Figure 3--12, Normal trigger mode.

H Auto mode sets the instrument to acquire a waveform even if a trigger event

does not occur. Auto mode uses a timer that starts after trigger rearm. If the

trigger circuit does not detect a trigger after this timeout (about 100 ms), it

auto triggers, forcing enough trigger events to acquire all active channels. In

the case of repetitive acquisitions in automatic trigger mode, waveform

samples are acquired, but at different places in the data stream (synchroniza-

tion is lost). See Figure 3-- 12, Automatic trigger mode. If you do not apply a

signal to any channel displayed, a baseline is displayed for that channel.

Triggered waveform Untriggered waveforms

Normal trigger mode Automatic trigger mode

Figure 3- 12: Triggered versus untriggered displays

1 2 ... 110 111 112 113 114 115 116 117 118 119 120 ... 353 354

Pas de commentaire

Tektronix CSA8000B Manuel d'utilisateur Page 115