Configuring the RF signal
R&S
®
SMM100A
365
User Manual 1179.1341.02 ─ 05
Since you need to determine an LF signal source for all modulations, "Source" and
"State" are described in general. These parameters apply to the modulation modes
AM, FM and
Φ
M. The following description explains the specific settings for the
appropriate modulation modes.
State
Activates a modulation.
Note:
Some modulations exclude each other and cannot be performed simultaneously.
For more information, see data sheet.
Remote command:
Source
Selects the LF signal source.
You can vary the signal sources for each of the modulations.
"LF Generator 1/2"
Selects one or both of the internally generated LF signals.
"External 1/2"
Selects an externally supplied LF signal.
"Noise Generator"
Selects the internally generated noise signal.
Remote command:
FM settings
The following settings are dedicated to FM.
Deviation ← FM settings
Sets the frequency modulation deviation in Hz.
The maximal deviation depends on the RF frequency and the selected modulation
mode (see data sheet).
Maximal possible deviation is selected automatically, if one of the following applies:
●
The selected deviation is too high for the particular frequency
●
The selected frequency is outside of the range where deviation is possible.
A warning message indicates this situation, too.
Remote command:
[:SOURce<hw>]:FM<ch>[:DEViation]
Deviation Mode ← FM settings
Enables you to couple the LF signal of both paths and determines the mode for fixing
the total deviation.
The total deviation is the sum of both paths. When the sum is exceeded, the
R&S
SMM100A reports a settings conflict, but does not change the settings.
Analog modulations