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PWM
PWM is applicable to pulse only so select Pulse then select PWM by pressing the MOD key to
show the display below.
Note that PWM is the only modulation type applicable to pulse so there is no
Type
soft-key to
allow selection of any other type.
To select the modulation source press the
Source
soft-key. The options are
Internal
or
External
. Internal will use the waveform specified in the shape parameter and the Graph Box will
show that shape as the modulating waveform. External will use the signal present at the MOD IN
connector and the
Freq
and
Shape
soft-keys will disappear. The Graph Box will always show a
sinewave as the modulating waveform if the source is set to external.
To set the pulse width deviation press the
Deviatn
soft-key. The deviation parameter will
appear in the Edit Box and the modulating waveform in the Graph Box will show that deviation is
being edited.
The deviation may be changed in either of the ways detailed in General: Numeric Editing.
To set the modulation frequency press the
Freq
soft-key. The frequency parameter will appear in
the Edit Box and the modulating waveform in the Graph Box will show that frequency is being
edited.
