3-13
Triggering the Oscilloscope
To use Edge triggering
Analog source Press the analog channel source softkey to select an analog
source. Adjust the trigger le vel for the sele cted analog ch annel by turni ng the
Trigger Level knob. The position of the trigger level for the analog channel is
indica ted by the tr igger level icon (if the analo g chan nel is on) at the f ar lef t
side of the display when DC coupling is selected. The value of the analog
channel trigger level is displayed in the uppe r-right corner of the display.
Digital source (mixed-signal oscilloscope) Press the digital source
softkey or turn the Entry knob to select a digital channel (D15-D0) as the trigger
source. Select Threshold in the D7 Thru D0 or D15 Thru D8 menu to set the
threshold level (TTL, CMOS, ECL, or user define d) for the selected digital
channel group. The threshold value is displayed in the upper-right corner of the
display.
External/Line source Ext (external trigger) and Line (trigge rs off the po wer
line frequency) trigger share the same softkey on the display. Toggle the softkey
to select the source you want.
The external trigger input is on the front pa nel of the 2-channel oscilloscope
and on the rear-panel of 4-channel and mixed-signal oscilloscope. You can
connect the trigger output of other instruments to this external trigger input,
or use an oscilloscope probe, such as the 10073C or 10074C.
Adjust the external trigger level for the selected analog channel by turning the
Trigger Level knob. The trigger level for Line is not adjustable.
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