[MSDN Library April 2000] Sonar Feature Leaves Rings on the Screen (57.0238095238095%)

MSDN Library - April 2000 > Knowledge Base > Hardware > Microsoft Natural Keyboard

[MSDN Library April 2000] Sonar Feature Does Not Appear in MS-DOS Prompt Session (42.6719576719577%)

MSDN Library - April 2000 > Knowledge Base > Hardware > Microsoft Natural Keyboard