DI-770 Oscilloscope provides five virtual instruments in one

DI-770 and WINDAQ/Scope Manual
Setting up a channel
The two channels of the oscilloscope are completely configurable. Both channels are identical, each has its own menu
item in the main menu. Since the possibilities for both channels are equal, channel 1 is explained here. Where channel
1 is described, the same applies to channel 2.
With the menu item Ch1 (or Ch2) from the main menu a popup menu is called with all settings for a channel.
Setting the sensitivity of a channel
The input sensitivity of a channel determines how large a certain signal will be displayed, the lower the full scale
value, the larger the signal will be displayed. It is also possible to enable an autoranging function.
The sensitivity can be set through the Sensitivity menu. The Sensitivity menu is called by enabling the Ch1 menu and
then selecting the Sensitivity menu. In this menu the input sensitivities are available. Also an Autoranging setting is
available. The Sensitivity menu can also be entered by clicking the right mouse button over one of the Ch1 or Ch2
controls and readouts.
To switch on Autoranging, a special button is available. When auto ranging is switched on, the button caption is Auto,
otherwise it holds the current set input sensitivity. Pressing the right mouse button on this button will bring up a menu
with all sensitivities.
Note: When autoranging is switched on, several measurements might be needed to set the input sensitivity, depending
on the input signal.
Another way to set the sensitivity is by using the keyboard. A few keys have been reserved for setting the input sensitivity
of the channels. These keys are:
Increase Ch1 sensitivity
Decrease Ch1 sensitivity
Increase Ch2 sensitivity
Decrease Ch2 sensitivity
Setting the signal coupling of a channel
The input signal can be coupled directly to the ADC (DC) or through a capacitor to the ADC (AC). In the hardware, a
capacitor is switched into (AC) or out of (DC) the signal path.
In COUPLING DC the complete signal (AC+DC) at the input is passed through. In COUPLING AC only the AC
component of the input signal is passed through. It is then possible to examine e.g. a ±20 mV ripple on a 30 V DC
voltage, since only the ripple is passed through and the DC voltage not. AC voltages with a frequency lower than ±4
Hz are not coupled correctly.
There are three different ways to set the coupling. Two ways are: by clicking the coupling button or by pressing keys.
The third way is through the Signal coupling menu.
The Signal coupling menu is called by enabling the Ch1 menu and then selecting the Signal coupling menu. In this
menu the settings Coupling AC and Coupling DC can be found. The menu can also be entered by clicking the right
mouse button over one of the Ch1 or Ch2 controls and readouts.
In the tool bar for each channel a coupling button is found, the coupling button for Ch1 at the left hand side of the
screen, for Ch2 at the right hand side of the screen. The picture at the button indicates the state of the coupling setting.
The left button of the two buttons below is indicating AC coupling, the right button is indicating DC coupling.
The current coupling state is displayed in the coupling button.
The Oscilloscope
32