PMX40 RF Power Meter – INSTRUCTION MANUAL
4-9
Trigger Mode:
Set the trigger mode for synchronizing data acquisition with
pulsed signals. Normal mode will cause a sweep to be triggered each time the
power level crosses the preset trigger level in the direction specified by the
trigger slope setting. If there are no edges that cross this level, no data
acquisition will occur. Auto mode operates in much the same way as Normal
mode but will automatically generate a trace if no trigger edges are detected
for a period of time (100 to 500 milliseconds, depending upon timebase). This
will keep the trace updating even if the pulse edges stop. The Auto PK-PK
mode operates the same as Auto mode but will adjust the trigger level to
halfway between the highest and lowest power or voltage levels detected.
This aids in maintaining synchronization with a pulse signal of varying level.
The Freerun mode forces unsynchronized traces at a high rate to assist in
locating the signal.
Trigger Source:
Set the trigger source used for synchronizing data acquisition.
The CH # settings use the signal from the associated sensor. Ext setting uses
the signal applied to the rear panel TRIG IN connector.
The trigger source can be any of the resource channels (CH1, CH2, etc.), or the Ext(ernal) trigger input
signal. The Ind(ependent) trigger setting allows each connected sensor to trigger independently from its
own RF input.
The external trigger is attached to the Trig In BNC connector on the rear of the PMX40 Power Meter and
requires a TTL signal level, minimum pulse width of 10 ns, and maximum frequency of 50 MHz.
Note
Connecting the Sync cable from the Multi I/O port on the sensor to the corresponding
Sync port on the instrument for the sensor in use is necessary if using an external trigger
or when performing measurements across multiple channels.
Trigger Slope:
Set the trigger slope or polarity. When set to +, trigger events will be generated when a
signal’s rising edge crosses the trigger level threshold. When – is selected, trigger events are generated
on the falling edge of the pulse.
4.4.8
MAIN
Markers
Marker #:
Set the time position of marker 1 or 2 relative to the
trigger. Note that time markers must be positioned within the time limits of
the trace window in the graph display. If a time outside of the display limits
is entered, the marker will be placed at the first or last time position as
appropriate.
Δ
Time:
Displays the result of Marker 2 - 1 in seconds. This item is
read only.