R&S SMJ100A, Operating Manual

Page: 263 / 874

Instrument Function
R&S
®
SMJ100A
247 Operating Manual 1403.7458.32 ─ 14
Remote command:
[:SOURce<hw>]:FM:STATe
on page 712
FM Source
Selects the source for the FM signal.
"Internal" Uses the internal LF generator as modulation signal source for FM.
"External" Uses an externally applied modulation signal.
The external signal is input via the EXT MOD connector.
"In External"
Uses both, the internal and externally applied modulation signal, for
example to perform two-tone FM.
Remote command:
[:SOURce<hw>]:FM:SOURce
on page 711
FM Mode
Selects the mode for the frequency modulation.
"Normal" The maximum range for modulation bandwidth and FM deviation is
available.
Remote command:
[:SOURce<hw>]:FM:MODE
on page 710
FM Deviation
Sets the modulation deviation in Hz.
The deviation is given as the absolute deviation in relation to the set center frequency,
for example a deviation 5
MHz at a center frequency of 1 GHz leads to a frequency
modulation between 995 MHz and 1005 MHz.
The maximum deviation depends on the RF frequency set and the selected modulation
mode (see data sheet). It is possible to enter a deviation that is too high for a certain
RF frequency or to vary the RF frequency to a range in which the deviation can no lon-
ger be set. In this case the maximum possible deviation is set and an error message is
displayed.
The deviation of the internal source must not exceed the deviation of the external
source in case of modulation source "Int+Ext".
Remote command:
[:SOURce<hw>]:FM[:DEViation]
on page 709
LF Gen Frequency
Sets the frequency of the LF generator.
This setting affects all analog modulations which use the LF generator as the internal
modulation source.
Remote command:
[:SOURce]:LFOutput:FREQuency
on page 738
FM Sensitivity
Displays the input sensitivity of the externally applied modulation signal at the EXT
MOD input in Hz/V.
RF Signal and Analog Modulations - RF Block