Rohde & Schwarz SMU200A - Automatic Level Control Menu

Instrument Function
R&S
®
SMU200A
222Operating Manual 1007.9845.32 ─ 15
Automatic Level Control is deactivated with pulse modulation!
When pulse modulation is activated, the ALC state of the R&S SMU is automatically
changed to "ALC OFF" ("Sample & Hold"). In this state, the ALC loop is opened and the
output level is not regulated but the level modulator is set directly. In order to set the
correct output level, a sample & hold measurement is executed after each frequency or
level setting.
The level is decreased by 30 dB during "Sample&Hold" measurement.
5.5.8.1 Automatic Level Control Menu
To open the "Automatic Level Control" menu, select "RF/A Mod > Configure > Automatic
Level Control" or use the MENU key under "RF/A Mod".
The combined menu "ALC / UCOR" is divided into the several sections and provides
access to the "Automatic Level Control" settings and to function "User Correction", see
chapter 5.5.9, "User Correction", on page 223).
The top sections of the dialog provide access to the level and attenuator settings (see
chapter 5.5.7.3, "Power-On/EMF Settings", on page 220 and chapter 5.5.7.2, "RF
Level", on page 217).
External Level Control is possible using R&S NRP power sensors, see chapter 5.5.6,
"NRP-Z Power Viewer", on page 210.
State - ALC
Activates/deactivates internal level control.
Note: Automatic Level Control is deactivated with pulse modulation!. When pulse mod-
ulation is activated, the ALC state of the R&S SMU is automatically changed to "ALC
OFF" ("Sample & Hold"). In this state, the ALC loop is opened and the output level is not
regulated but the level modulator is set directly. In order to set the correct output level, a
sample & hold measurement is executed after each frequency or level setting.
in Auto mode if the level is in the High Power range, i.e. the mechanical relay bypass is
switched.
RF Signal and Analog Modulations - RF Block