184 Keysight M8000 Series of BER Test Solutions User Guide
4 User Interface - M8020A Display Views
Notice that the icon appears on the top right of the Impairment
Setup View which indicates that the filter has been applied.
If the channels are selected but their corresponding parameters are not
selected, a message that no parameters are selected will be displayed.
The icon also appears in front of each item whose corresponding
parameters are not selected. If you move the mouse pointer on this icon, a
tool-tip message is displayed as shown in the following figure:
It is mandate to select at-least one channel. Failing this will display a
message on the Impairment Setup View window that no channels are
selected.