Selecting a
Sweep
Trigger
There are three modes of sweep triggering provided
for analog sweep and step sweep—automatic, exter-
nal, and single. The sweep trigger is selectable from
the trigger menu. The following is a description of
each mode.
qAuto (Automatic)–The sweep continually
sweeps from its start frequency to its stop fre-
quency with optimal retrace time.
qExternal–The sweep recurs when triggered by
an external TTL-compatible clock pulse to the
rear panel AUX I/O connector.
qSingle–Asingle sweep starts when the trigger
key is pressed. If a sweep is in progress when
the key is pressed, it aborts and resets.
Togo to the Sweep Trigger Menu (below) from the
Analog Sweep Ramp menu, press TriggerMenu .
Toselect a sweep trigger mode, press its menu soft-
key.A message showing the sweep trigger mode se-
lected appears on the right side of frequency title
bar.When you are finished, press Previous Menu to
return to the Analog Sweep Ramp Menu display.
If you select the single sweep trigger mode, the
menu display adds the menu soft-key Trig. Press-
ing Trig startsa single sweep. If a single sweep is
in progress, pressing Trig causesthe sweep to abort
and reset.
3-28 681XXC OMLOCAL (FRONT SWEEP FREQUENCY
PANEL) OPERATION OPERATION