Raytheon Pathfinder ECDIS Operator's Manual page 48

2.3.7 Using Option Buttons
Option buttons are the small circular buttons with labels beside them. Option
buttons are either selected or cleared. Selected option buttons have dark
centers; cleared option buttons have empty centers. Option buttons are usually
mutually exclusive − that is, only one button in a group can be selected at a time.
2.3.7.1 Select or Clear an Option Button with Trackball
Point and click on the option button or its label.
2.3.7.2 Select or Clear an Option Button with Keyboard
Press [Tab] until the focus rectangle (dotted box) surrounds the label of the
option button.
Or, if multiple option buttons are grouped together in a box, press [Tab] until the
focus rectangle (dotted box) outlines the label of one of the buttons in the group.
Then, use the arrow keys to move from one option button to the next. As you
move from button to button, they are alternately selected, then cleared.
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Operator Manual
Figure: 1−15 Option Buttons
2−18
Option Buttons
Edition: 30.MAR.2007