Common measurement settings
R&S
®
FSVA3000/ R&S
®
FSV3000
427
User Manual 1178.8520.02 ─ 08
Mismatched settings on multiple connected instruments
When multiple instruments are connected to the same frontend at the same time, both
channels use the same internal LO and thus both signal paths operate on the same
frequency. Therefore, if you want to analyze the signal from the generator using the
same frontend, make sure the
instruments.
If multiple instruments use the same frontend at the same time, the frequency conver-
sion settings are identical for all connected instruments. Thus, if you change a fre-
quency setting on one instrument while the other is performing a measurement, the
measurement results no longer match the original measurement settings. In this case,
an error message is displayed ("Settings mismatch"). To restore the original measure-
ment settings on the frontend, change a frontend setting in the R&S
FSV/A dialog. See
also
Activation
External frontends are activated for each application on the R&S
FSV/A individually.
Only one application can use the frontend at the same time.
Activation is a two-step process. First, global activation allows for the general use of an
external frontend for the application. The application adapts the available measure-
ment settings to the connected frontend, for example the available frequency range,
reference level and attenuation. If no frontend is configured yet, the configuration set-
tings become available. The channel bar indicates "Inp: ExtFe".
In a second step, the configured frontend is connected. Due to the two-step process,
the frontend can be deactivated temporarily for use by another connected instrument,
for example if the frontend has two signal paths. The measurement settings on the
R&S
FSV/A remain untouched.
If global activation is stopped, the application adapts the measurement settings to the
common settings supported by the R&S
FSV/A.
Calibration and alignment
The calibration data for the RF input and output signal paths of the frontend are stored
on the device. The R&S
FSV/A reads out the data from the connected frontend and
aligns the measured data accordingly. The IF cable used to transfer data from the
external frontend to the RF input of the R&S
FSV/A must be calibrated during initial
connection. Usually, this cable is part of the fixed test setup and is not changed regu-
larly. The calibration data for the IF cable is often provided with the cable as a touch-
stone (
.s2p
) file. The R&S
FSV/A can read such files and adapt the measurement
results to the frequency response of the cable. To provide valid results, the frequency
response file must cover the used frequency range of the external frontend.
Frequency response files are usually provided with the IF cable. The calibration data
for the IF cable provided with the R&S
FSV/A is installed on the instrument at the fac-
tory.
Data input and output
