Common Measurement Settings
R&S
®
FSW
399
User Manual 1173.9411.02 ─ 19
The parameters "Input Coupling" and "Impedance" are identical to those in the "Input"
settings, see
chapter 6.2.2, "Input Source Settings"
Preamplifier (option B24) ← Input Settings
If option R&S
FSW-B24 is installed, a preamplifier can be activated for the RF input
signal.
You can use a preamplifier to analyze signals from DUTs with low input power.
For R&S
FSW 26 or higher models, the input signal is amplified by 30 dB if the pream-
plifier is activated.
For R&S
FSW 8 or 13 models, the following settings are available:
"Off"
Deactivates the preamplifier.
"15 dB"
The RF input signal is amplified by about 15 dB.
"30 dB"
The RF input signal is amplified by about 30 dB.
Remote command:
Noise cancellation
The results can be corrected by the instrument's inherent noise, which increases the
dynamic range.
In this case, a reference measurement of the instrument's inherent noise is carried out.
The measured noise power is then subtracted from the power in the channel that is
being analyzed (first active trace only).
The inherent noise of the instrument depends on the selected center frequency, resolu-
tion bandwidth and level setting. Therefore, the correction function is disabled when-
ever one of these parameters is changed. A disable message is displayed on the
screen. To enable the correction function after changing one of these settings, activate
it again. A new reference measurement is carried out.
Noise cancellation is also available in zero span.
Currently, noise cancellation is only available for the following trace detectors (see
●
RMS
●
Average
●
Sample
●
Positive Peak
Remote command:
6.4.3 Scaling the Y-Axis
The individual scaling settings that affect the vertical axis are described here.
Amplitude and Vertical Axis Configuration
