PMX40 RF Power Meter – INSTRUCTION MANUAL
4-8
4.4.6
MAIN
Time
Timebase:
Controls the timebase or horizontal scale of the acquisition
and is noted on the horizontal axis label 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.
Trig Delay:
The trigger delay time is set in seconds with respect to the
trigger. Positive values mean 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.
4.4.7
MAIN
Trigger
Trigger Holdoff:
Set the trigger holdoff time. Trigger holdoff is used to disable the trigger for a specified
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 trigger 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
holdoff 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).
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 from 0 to 20 dB, then
the offset-adjusted trigger level will be displayed to the user as 30 dBm. Likewise, the maximum trigger
level range will be extended to 40 dBm. The trigger level set point and setting range are both shifted
upward by 20 dB.
