Common Measurement Settings
R&S
®
FSW
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User Manual 1173.9411.02 ─ 19
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Remote command:
Adjusting the Center Frequency Automatically (Auto Freq)
This function adjusts the center frequency automatically.
The optimum center frequency is the frequency with the highest S/N ratio in the fre-
quency span. As this function uses the signal counter, it is intended for use with sinus-
oidal signals.
Remote command:
Setting the Reference Level Automatically (Auto Level)
Automatically determines the optimal reference level for the current input data. At the
same time, the internal attenuators and the preamplifier (for analog baseband input:
the full scale level) are adjusted so the signal-to-noise ratio is optimized, while signal
compression, clipping and overload conditions are minimized.
In order to do so, a level measurement is performed to determine the optimal reference
level.
You can change the measurement time for the level measurement if necessary (see
"Changing the Automatic Measurement Time (Meastime Manual)"
Remote command:
Resetting the Automatic Measurement Time (Meastime Auto)
Resets the measurement duration for automatic settings to the default value.
(Spectrum application: 1
ms)
Remote command:
Changing the Automatic Measurement Time (Meastime Manual)
This function allows you to change the measurement duration for automatic setting
adjustments. Enter the value in seconds.
Remote command:
Upper Level Hysteresis
When the reference level is adjusted automatically using the
internal attenuators and the preamplifier are also adjusted. In order to avoid frequent
adaptation due to small changes in the input signal, you can define a hysteresis. This
setting defines an upper threshold the signal must exceed (compared to the last mea-
surement) before the reference level is adapted automatically.
Remote command:
Adjusting Settings Automatically
