User manual

Publication No. 980935 Rev. M 3152B User Manual
Astronics Test Systems ArbConnection 4-21
FM
The FM panel (Figure 4-14)
contains parameters for controlling the
amplitude modulat
ion function. To turn the FM function on and off,
click on the FM button in the State group. The various groups in the
FM panel are described below.
State
The State button turns the FM function on and off.
FM Parameters
This group contains parameters that allow complete control over the
FM function. These are:
CW Frequency – The CW Frequency is the frequency of the pre-
modulation carrier waveform. In case the modulating waveform is
one of the built-
in standard waveforms, the modulation will be
symmetrical about the CW frequency setting.
Baseline –
The Baseline parameter affects the output
characteristics in one of the interrupted run modes (i.e., triggered,
burst). In this case this parameter defines where the signal idles
between triggers. There are two op
tions: CW and DC. The DC
option will set the idle state to a DC level, meaning that in between
triggers, the output resides on a DC
level and generates modulation
when a trigger is accepted. The CW is similar except the signal
idles on the pre-trigger CW f
requency setting, executes the
modulation upon receipt of a legal trigger signal and returns to
continuous CW frequency output.
Figure 4-14, FM Panel
Standard FM Parameters -
These parameters are active only
when one of the built-in
waveforms is selected as the modulating
signal. These are: Sine, Triangle, Square, or Ramp. The modulation
frequency, deviation and marker frequency control the standard FM
modulation scheme.
Modulating Wave - Defines the shape of the modulating waveform.
There are two basic options: Standard (built-in) waveforms and