54
Burst
General
All waveforms can be run using the Burst function with the exception of Noise. The burst function
allows the carrier waveform to be triggered, produce a user specified number of cycles and then
stop and wait for the next trigger. For a PRBS waveform burst the count is PRBS clocks and not
PRBS cycles. This allows the generation of incomplete or multiple sequences. A new trigger always
restarts the PRBS from the start.
Alternatively the number of cycles may be Infinite. In this case the trigger starts the waveform and
the next trigger stops the waveform. As above, PRBS waveforms will be triggered from the start.
The Gated Burst function causes the carrier waveform to run while the trigger is true and stop while
the trigger is false. The gated function is also available with Noise as the carrier waveform.
In all the above cases, except Noise and PRBS, the operation will always produce an exact number
of cycles of the carrier waveform.
The trigger signal for the burst can be internal from the trigger generator, the other channel,
external from the TRIG IN connector or manual by pressing the TRIGGER key.
Pressing the BURST key will apply the currently selected burst parameters to the currently selected
carrier waveform and the BURST key will glow yellow. The screen below shows the effect of
pressing the BURST key when sine is the selected waveform.
The Parameters Box now shows the current burst parameters of
TYPE
,
PHASE
, and
TRIGGER
and
Burst
is shown in the
FCN
field. The Graph Box shows the burst waveform trigger below a
representation of the carrier waveform. The Edit Box contains the selected parameter, in this case
type.
To change the carrier waveform parameters press the highlighted carrier waveform key which will
return the display to the carrier menu as shown below.
Notice that
Burst
still shows in the
FCN
field of the Parameters Box and the BURST key still
glows yellow indicating that burst is still active. To return to the Burst menu to edit the burst
parameters press the BURST key again. To turn off burst press the BURST key while the Burst
menu is displayed.
The following sections discuss the parameter choices for burst.
