Using the Oscilloscope
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Measurement Using the Tri gger Control Fields:
•From Controls select the desired trigger source:
•Internal uses the signal being displayed.
•Ext (TTL) uses the signal con nec te d t o t he r ear p ane l EXT SCOP E
TRIGGER INPUT connector.
•Encoder uses the optional signaling encoder.
• Trigger mode is selected as follows:
• In Auto, a trigger is automatically generated every 50ms (unless a
normal trigger is received).
• In Norm, a defined trigger required.
• In Cont, the oscilloscope sweeps on each trigger occurrence.
• In Single, the oscilloscope sweeps once on a trigger occurrence af-
ter Reset is selected.
•Level (div) sets the internal trigger level (vertical divisions). Pos selects
triggering for positive going signals. Neg sele cts trig gering for ne gative
going signals. Pointer indicates level.
•Pre-Trig sets the number of horizontal divisions to be displayed prior
to the trigger. Pointer indicates pre-tr igger point.
Indicators:
•Marker Time ms changes the units that the marker position is dis-
played in. Displayed value is the time elapsed from the trigger poin t
to the current position.
•Marker Lvl V/kHz/% changes units that the marker position is dis-
played in. Displayed value is signal level at current position.