Pulse Modulation Settings - R&S SMB100A Operating Manual

®
R&S SMB100A
Automatic Level Control is deactivated with pulse modulation!
When pulse modulation is activated, the R&S SMB deactivates ALC automatically
("ALC OFF", i.e. switches to "Sample & Hold" state).
The "Sample&Hold" state opens the ALC loop, and disables the automatic control of
the output level. The level modulator is set directly.
However, to correct the output level, the R&S SMB executes a "Sample & Hold" mea-
surement after each change of frequency or level settings.
The level is decreased by 30 dB during "Sample & Hold" measurement.
5.4.5.1

Pulse Modulation Settings

► To access the "Pulse Modulation" settings, select "Modulation > config... > Pulse
Modulation".
The dialog contains all parameters for configuring a pulse modulation signal, com-
prising the signal source, pulse generator and trigger settings.
Depending on the selected modulation source, the provided parameters vary:
●
"Source Pulse Generator"
Displays the parameters for configuring the pulse generator signal, which in turn
vary according to the selected "Mode > Single / Double ...".
Note: Extended features as the generation of double pulse signals or selectable
trigger mode require option R&S SMB-K23.
●
"External"
Enables you to configure the polarity of an externally supplied pulse modulation
signal.
Additionally, you can use the internally generated Valid Signal for synchronization of
the pulse modulation, and assign this signal to the VALID SIGNAL connector, see
Chapter 5.5.4.1, "Pulse Generator
Note: The pulse generator settings in this dialog are mirrored from the actual "Pulse
Generator" dialog of the "Mod Gen" block. Therefore find the description on the access
Operating Manual 1407.0806.32 ─ 21
Settings", on page 226 for description.
Instrument Function
Modulation
210