Tabor Electronics 5251, Руководство пользователя

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3
ArbConnection
Generating Waveforms Using the Equation Editor
3-45
Equation
The Equation group has four buttons and the equation field. You will
be using the Equation field for writing your equations. Equation
syntax and conventions are discussed in the following paragraphs.
The
Remove button clears the equation field so you can start typing
a new equation. Click on the Store button to store your equation if
you intend to use it again. The Browse button provides access to
waveform pre-stored files in your computer for combining them in
new equations. The
Operands button expands the bottom of the
dialog box to show the operands you can use with your equation.
While you type and store equations, they are collected in a history
file and can be used again by expanding the history log from the
equation field.
Control Buttons
There are four control buttons at the right corner of the dialog box.
Use the
Preview button to preview an image of your equation, or
use the OK button to place your waveform on the waveform screen
and to leave the dialog box on the screen. The Default button
restores the parameters in the equation editor to their original
factory default values. The
Cancel button will remove the dialog box
from the screen and will discard of any waveforms that you
previewed with your Equation Editor.
Writing Equations
The Equation Editor lets you process mathematical expressions
and convert them into waveform coordinates. As you probably
already know, waveforms are made of vertical samples. The
number of samples on your waveform is determined by the
wavelength parameter. For example, if you have 1024 horizontal
points, your equation will be computed along 1024 points as a
function of the vertical scale. Each vertical sample is computed
separately and placed along the horizontal axis. The points are
graphically connected to form a uniform and continuous waveform
shape however, if you zoom in on a waveform line, you’ll see that
the points are connected like a staircase. In reality, the 5251
generates its waveforms exactly as shown on the screen but, if the
waveform has many horizontal points, the steps get smaller and
harder to see without magnification.
Equations are always computed as a function of the vertical
(Amplitude) axis therefore the left side of your equation will always
look as Amplitude(p)=, where “p” is the equation variables in units of
waveform points. You can write equations with up to 256
characters. If the equation is too long to fit in the visible field, parts
to the left or right will scroll off the ends.