Configuration
R&S
®
FSW-K7
91
User Manual 1173.9240.02 ─ 23
Note:
Electronic attenuation is not available for stop frequencies (or center frequencies
in zero span) >
13.6
GHz.
In "Auto" mode, RF attenuation is provided by the electronic attenuator as much as
possible to reduce the amount of mechanical switching required. Mechanical attenua-
tion may provide a better signal-to-noise ratio, however.
When you switch off electronic attenuation, the RF attenuation is automatically set to
the same mode (auto/manual) as the electronic attenuation was set to. Thus, the RF
attenuation can be set to automatic mode, and the full attenuation is provided by the
mechanical attenuator, if possible.
Both the electronic and the mechanical attenuation can be varied in 1 dB steps. Other
entries are rounded to the next lower integer value.
For the R&S
FSW85, the mechanical attenuation can be varied only in 10
dB steps.
If the defined reference level cannot be set for the given attenuation, the reference
level is adjusted accordingly and the warning "Limit reached" is displayed in the status
bar.
Remote command:
Input Settings
Some input settings affect the measured amplitude of the signal, as well.
For details see
Chapter 5.3.1, "Input Source Settings"
Preamplifier ← Input Settings
If the (optional) Preamplifier hardware is installed, a preamplifier can be activated for
the RF input signal.
You can use a preamplifier to analyze signals from DUTs with low output power.
This function is not available for input from the (optional) Digital Baseband Interface.
For R&S
FSW26 or higher models, the input signal is amplified by 30 dB if the pream-
plifier is activated.
For R&S
FSW8 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:
Input Coupling ← Input Settings
The RF input of the R&S
FSW can be coupled by alternating current (AC) or direct cur-
rent (DC).
This function is not available for input from the optional Digital Baseband Interface or
from the optional Analog Baseband Interface.
Input and Frontend Settings
