Ronde & Schwarz 1304.0004K03, User Manual

Page: 316 / 1071

The Spectrum Application (RF Measurements)
R&S
®
FPL1000
316 User Manual 1178.3370.02 ─ 11
For GSM and Avionics measurements, the impedance is always 50
Ω
and cannot be
changed.
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
).
This value also affects the unit conversion (see "Reference Level" on page 313).
Remote command:
INPut<ip>:IMPedance
on page 780
Preamplifier
If the (optional) internal preamplifier hardware is installed, a preamplifier can be activa-
ted for the RF input signal.
You can use a preamplifier to analyze signals from DUTs with low output power.
Note: If an optional external preamplifier is activated, the internal preamplifier is auto-
matically disabled, and vice versa.
The input signal is amplified by 20 dB if the preamplifier option is activated.
Remote command:
INPut<ip>:GAIN:STATe
on page 768
6.5.3 Scaling the Y-Axis
The individual scaling settings that affect the vertical axis are described here.
Access : "Overview" > "Amplitude" > "Scale" tab
Or : [AMPT] > "Scale Config"
The remote commands required to define these settings are described in Chap-
ter 10.8.3, "Configuring the Vertical Axis (Amplitude, Scaling)" , on page 765.
Amplitude and Vertical Axis Configuration