DI-770 Oscilloscope provides five virtual instruments in one

DI-770 and WINDAQ/Scope Manual
is changed to the new value. Then a vertical line is drawn between the lowest and highest value. So a glitch is always
captured.
Envelope mode is reset each time when the setting of the instrument changes (sensitivity, offset, record length etc.),
when the window size changes and when the pre defined reset number is reached. To set the reset number, enter the
Envelope menu, which can be found in the Measure menu or by clicking the right mouse button on the Envelope
mode button ( ). Select the item Reset envelope after and a menu with the possible option pops up. When the
choice 32 measurements is selected, envelope mode will be reset after 32 measurements. When the choice infinite
measurements is selected, envelope mode will not be reset automatically, only by changes in the instrument settings
or by a window size change.
Envelope mode can be switched on by clicking the envelope button, by pressing the key or be selecting the item
Envelope mode from the Measure menu. When envelope mode is switched on, the Envelope button stays down.
Envelope mode is switched off by pressing the button again, pressing the key again or by selecting the Envelope
mode menu item again.
Note: Envelope mode is only a display function. The envelope signal is not stored to disk or printed in a hardcopy
operation.
Averaging
When a noisy signal is measured, the influence of the noise can be eliminated by averaging several measurements.
The noise component(s) will disappear and the actual signal remains.
Averaging can be switched on by selecting the item Perform averaging of from the Measure menu. In the next menu a
number of measurements can be selected that have to be averaged. The item 1 measurement will switch off averaging.
Averaging can also be switched on or off by pressing the Averaging button ( ).
When averaging is set to e.g. 20 measurements and the oscilloscope is set to Pause, pressing the One shot button will
result in taking 20 measurements which are averaged
Averaging is reset each time when the setting of the instrument hardware changes (sensitivity, coupling, sampling frequency,
record length etc.) and when the pre defined reset number is reached.
Note: When a number of pre samples is set, averaging will have a large effect on the shape of the signal in the pre
samples because this part of the measured record changes much.
Math mode
The oscilloscope is equipped with a special Math channel. This channel can display the following signals:
Ch1 + Ch2
Ch1 - Ch2
Ch2 - Ch1
These are display added or subtracted signals. This means that the on screen signal sizes are added or subtracted. The
position and size of the math signal can be controlled by the software offset and software gain of both channels.
To get a math channel, both channels have to be on. Selecting a math channel is done by selecting a menu item from
the Math menu. The Math menu can be found in the main menu or can be called by clicking the math button ( ).
Hint: When the oscilloscope operates in split screen mode and ch1 uses the upper half of the screen and ch2 uses the
lower half of the screen, the math channel comes in the center of the screen.
The math channel can be switched off again by selecting the item No math from the Math menu.
The Oscilloscope
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