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R&S FSH
Spectrum Analyzer Mode
Configuring Spectrum Measurements
Operating Manual 1173.6275.12 - 30
106
In some cases it may be sufficient to get the results over a single sweep only, e.g. if a
particular trigger condition is met. In single sweep mode, the R&S FSH performs the
sweep a certain number of times (depending on the number of averages you have set)
over the defined range of the horizontal axis (frequency or time) and then stops
measuring. It performs another sweep only after you tell it to. For more information on
setting the number of sweeps included in a single sweep see "
Mode (Average)
".
► Press the SWEEP key.
► Press the "Single Sweep" softkey.
The R&S FSH activates single sweep mode.
► Press the "Cont Sweep" softkey.
The R&S FSH again starts to measure continuously.
3.2.4.3 Working with Trigger Functionality
If you have to perform measurements according to certain signal conditions, you can
use a trigger. A trigger responds to certain events. If a trigger is active, the R&S FSH
starts to measure if the trigger conditions are met. The trigger can be generated either
externally or internally.
Selecting the trigger source
► Press the SWEEP key.
► Press the "Trigger" softkey.
The R&S FSH opens a submenu to select the trigger source.
► Select the trigger source you need.
The R&S FSH activates the trigger.
The R&S FSH provides the following trigger functions.
●
Free Run
A new sweep starts on completion of the previous sweep. This is the default state
of the R&S FSH.
●
Video Trigger
A sweep starts when the video voltage exceeds a particular level. The video trigger
is available only in the time domain (span = 0).
In the frequency domain, the R&S FSH would never start a measurement with the
video trigger because there is no guarantee that there is a signal that generates
video voltage present at the start frequency.
●
External Trigger
(rising or falling slope)
A sweep starts on the rising edge (RISE) or on the falling edge (FALL) of an
external trigger signal. The external trigger signal is fed in via the BNC connector
"Ext Trigger". The switching threshold is 1.4 V, i.e. a TTL signal level.