Rohde & Schwarz SMB100A - Phase Modulation (Phim)

Instrument Function
R&S
®
SMB100A
175Operating Manual 1407.0806.32 ─ 13
The modulation depth entered under "FM Depth" is reached with 1 Volt (= U
peak
) of the
input signal.
Note: The input voltage should not exceed 1.1 V
p
otherwise modulation distortions might
occur.
Remote command:
[:SOURce<hw>]:FM:SENSitivity? on page 302
Adjust FM Offset
Starts the adjustment for the FM/PhiM modulator. The option is adjusted with respect to
DC-offset.
Remote command:
:CALibration<hw>:FMOFfset[:MEASure]? on page 250
FM External Coupling
(Source External only)
Selects the coupling mode (AC or DC) for external feed.
Note: Coupling for external feed via input MOD EXT is set for all modulations with external
source.
"AC"
The d.c. voltage content is separated from the modulation signal.
"DC"
The modulation signal is not altered.
Remote command:
[:SOURce<hw>]:FM:EXTernal:COUPling on page 300
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.
Remote command:
[:SOURce<hw>]:INPut:MODext:IMPedance on page 310
5.4.4 Phase Modulation (PhiM)
It is not possible to use phase modulation simultaneously with frequency modulation.
An internal and/or external source can be selected for phase modulation. The LF GEN
modulation generator is available as the internal source.
The MOD EXT input connector for external feed of analog modulation signals is at the
front of the instrument. The coupling mode of the input (AC or DC) and the impedance
can be selected.
Modulation