Configuration
R&S
®
VSE-K149
32
User Manual 1179.3315.02 ─ 01
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.
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 information on other input settings see
Chapter 4.2.1.1, "Radio Frequency Input"
Preamplifier ← Input Settings
If the (optional) internal preamplifier hardware is installed on the connected instrument,
a preamplifier can be activated for the RF input signal.
Note that if an optional external preamplifier is activated, the internal preamplifier is
automatically disabled, and vice versa.
For an active external frontend, a preamplifier is not 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.
Depending on the connected instrument, different settings are available. See the
instrument's documentation for details.
Remote command:
Impedance ← Input Settings
For some measurements, the reference impedance for the measured levels of the con-
nected instrument can be set to 50
Ω
or 75
Ω
.
Select 75
Ω
if the 50
Ω
input impedance is transformed to a higher impedance using a
75
Ω
adapter of the RAZ type. (That corresponds to 25
Ω
in series to the input impe-
dance of the instrument.) The correction value in this case is 1.76 dB = 10
log (75
Ω
/
50
Ω
).
Remote command:
Input and Frontend Settings
