Instrument Function
R&S
®
SMBV100A
199
Operating Manual 1407.6062.32 ─ 08
Note:
Coupling for external feed via input EXT MOD can be set independently for all
modulations with external source.
"AC"
The DC voltage content is separated from the modulation signal.
"DC"
The modulation signal is not altered.
SCPI command:
External Input Impendance
(Source External only)
Selects the impedance for external feed via the EXT MOD input.
Selection 600 Ohm and high (>100 kOhm) is available.
Note:
This setting affects all analog modulations which use the external modulation
source.
SCPI command:
5.4.12.5
Pulse Modulation (PM)
External and internal Pulse modulation requires options R&S SMBV-K22, Pulse Modu-
lator and R&S SMBV-K23, Pulse Generator.
An internal or external source can be selected for pulse modulation. In case of external
source, the external signal is input via the PULSE EXT connector at the rear of the instru-
ment. In case of internal source, this connector can be used as external trigger or gate
signal input for internal pulse modulation. The polarity and input impedance of the con-
nector can be selected.
The pulse signal is output at the PULSE VIDEO connector at the rear of the instrument.
Automatic Level Control is deactivated with pulse modulation!
When pulse modulation is activated, the ALC state of the R&S SMBV 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.
Pulse Modulation Settings
To open the "Pulse Modulation" menu, select "RF/A Mod > Configure > Pulse Modula-
tion" or use the MENU key under "RF/A Mod".
In the upper section of the menu, the modulation source is selected and the modulation
switched on. The configuration of the selected external and/or internal modulation source
is performed in the lower section of the menu.
The menu varies according to the selected modulation source.
RF Signal and Analog Modulations - RF Block
Summary of Contents for SMBV100A
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