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Operation 34
4.3.7 Time >
To enter the Time menu press the icon then select the Time tab.
Timebase
Controls the timebase, horizontal scale, of the Trace View. The Timebase pulldown
menu permits selection of fixed timebase ranges from 5 ns/div to 50 ms/div (sensor
series dependent) in a 1-2-5 progression.
Position
Sets the location of the trigger point on the acquired trace waveform. The Trig Delay
setting is in addition to this setting, and will cause the trigger position to appear in a
different location.
Figure 4.13
Time Setttings
Trig Delay
The trigger delay time is set in seconds with respect to the trigger. Positive values means that the trace display shows a
time interval after the trigger event. This positions the trigger event to the left of the trigger point on the display, and
is useful for viewing events during a pulse, or some fixed delay time after the rising edge trigger. Negative trigger delay
mean that the trace display shows a time interval before the trigger event, and is useful for looking at events preceding
the trigger edge.
4.3.8 Trigger >
To enter the Trigger menu press the icon then select the Trigger tab.
Trigger Holdoff
Set the trigger holdoff time. Trigger holdoff is used to disable the trigger for a spec-
ified amount of time after each trigger event. The holdoff time starts immediately
after each valid trigger edge and will not permit any new triggers until the time has
expired. When the holdoff time is up, the trigger re-arms, and the next valid trig-
ger event (edge) will cause a new sweep. This feature is used to help synchronize the
power meter with burst waveforms such as a TDMA or GSM frame. The trigger hold-
off resolution is 0.01 microseconds, and it should be set to a time that is longer than
the burst duration but shorter than the frame repetition interval.
Trigger Level
Sets the threshold level for the trigger signal used in the Auto and Normal trigger
modes. The trigger level can be entered numerically or changed by using arrow keys.
The trigger level range has a range that is sensor model dependent (see the sensor
specifications for your specific sensor model).
Figure 4.14
Trigger Setttings
The trigger range is automatically adjusted to include the dB Offset parameter set for the
source channel. For example, if the trigger level = 10 dBm and the dB Offset is changed