The Spectrum Application
R&S
®
FPC
112
User Manual 1178.4130.02 ─ 07
●
For TDMA Power measurements.
●
For measurements with a gated trigger.
●
If the frequency span is smaller than the resolution bandwidth (RBW).
●
If the the resolution bandwidth (RBW) is greater than 300 kHz.
14.7
Trigger Configuration
Access
: "Sweep"
Access
: "Setup" > "Config Overview" > "Trigger" (selected settings)
Remote commands to trigger measurements:
●
It often makes sense to capture data only when interesting events occur in the spec-
trum or only capture parts of a signal. In such cases, you can use a trigger. A trigger
responds to certain events. When you use a trigger, the analyzer starts a measurement
only when certain trigger conditions are met.
Selecting the trigger source
The trigger source selects the type of event whose condition must be met to start data
acquisition.
1. Press the "Sweep" key to open the sweep menu.
2. Select the "Trigger" menu item to open the trigger menu.
3. Select one of the trigger sources.
● "Free Run"
No trigger source is considered. You can start the measurement manually any
time and stop it as required.
● "Video Trigger"
A measurement starts when the voltage of the video signal exceeds a certain
level.
When you select the video trigger, the R&S
FPC opens an input field to define
the trigger level that the video signal must meet or exceed. The video trigger
level is a percentage of the diagram height (0
% to 100
%). A small symbol on
the diagram's y-axis ( ) indicates the absolute trigger level.
The video trigger is available for time domain measurements (span = 0). (In the
frequency domain, a measurement would never start with the video trigger
because there is no guarantee that there is a signal that generates video volt-
age at the start frequency.)
● "External Rise" / "External Fall"
A measurement starts on the rising or falling edge of an external trigger signal.
"External Rise": the measurement starts when the trigger signal rises above
1.4
V (a TTL signal level).
Trigger Configuration
