R&S SMJ100A, Operating Manual, Page: 264 / 874

Instrument Function
R&S
®
SMJ100A
248 Operating Manual 1403.7458.32 ─ 14
The modulation deviation entered with FM Deviation is achieved 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 711
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 522
FM External Coupling
(Source External only)
Selects the coupling mode (AC or DC) for the externally applied frequence modulation
signal.
Note: Coupling for external feed via input EXT MOD can be set independently for all
modulations using the external modulation signal.
"AC" Disconnects the DC voltage component and uses only the AC com-
ponent of the modulation signal.
"DC" Uses the modulation signal with both components, AC and DC.
Remote command:
[:SOURce<hw>]:FM:EXTernal:COUPling
on page 710
External Input Impedance
(Source External only)
Sets the impedance for the external modulation signal, applied at the EXT MOD con-
nector.
You can select 50 Ohm or high (>100 kOhm).
Note: The selection of 50 Ohm to ground requires that your instrument is equipped
with the extended synthesis assembly (SynEx).
This setting affects all analog modulations which use the external modulation signal.
Remote command:
[:SOURce<hw>]:INPut:MODext:IMPedance
on page 721
5.5.11.5 Phase Modulation (PhiM)
Phase modulation (
ɸ
M) requires option R&S SMJ-B20 (FM/
ɸ
M Modulator).
It is not possible to use phase modulation simultaneously with frequency modulation.
See
"Simultaneous Operation of Several Modulations or Other Operating Modes"
on page 241 for an overview in detail.
RF Signal and Analog Modulations - RF Block