Tabor Electronics 5064, Руководство пользователя

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2074
User Manual
3-54
The final step before the modified pulse shape will be available at
the output connector is pressing the Apply Changes soft key.
NOTE
No change will be made on the pulse shape and at the
output connector before the Apply Changes button has
been pressed, except when the High and Low Level
buttons are exercised. This was done to let the internal
computing circuit do the calculation of the pulse
parameters only once every time one or more
parameters have been modified.
Adjusting the pulse shape with the required characteristics can only
be done if all of its parameters can be adjusted both in the time and
amplitude domain. The Model 2074 provides all the necessary
controls to do just that. However, always bear in mind that the pulse
is being generated digitally and therefore there are some limitations
that would have to be observed. These limitations will be discussed
later in this chapter. Below you will find a list of all pulse parameters
that you’ll be able to access though the soft key menus.
Pulse Generator
Menus
Apply Changes
This, by far, is the most important key to understanding the pulse
generation process. The 2074 is actually an arbitrary waveform
generator, not a pulse generator however, with some firmware
changes, the same memory that is being used by the arbitrary
waveform function can be converted to design pulse shapes. In this
case, every change of pulse period, parameter or transition,
requires re-computation of the pulse shape and download
sequence to the arbitrary waveform memory. The process is critical
to assure that the pulse design was done within the legal
boundaries and generation capabilities of the model 2074. To avoid
multiple design conflicts and tedious exploration of why a pulse
cannot be designed with this or that parameter, the Apply Changes
button makes the choice only once at the end of the pulse design.
Therefore, always make sure that after you complete the design of
your pulse, press the Apply Changes soft key button to end the
design process and to route the new pulse design to the output
terminal.
Period
The period defines the repetition rate of the pulse. The period is
programmable from 80 ns.
Delay
The delay defines the time the pulse is delayed from its start to the
first transition. The delay times is computed as part of the pulse
period and therefore, if you do not plan to have a delayed pulse,
change its value to 0 s.