This movie shows how to count encirclements of the -1 point by the Nyquist diagram. Whenever another counterclockwise encirclement is realized, the counter on the bottom increases by 1.

Note: This is actually the opposite of the convention used in this tutorial. For our convention (clockwise encirclement positive), each anti-clockwise encirclement of -1 actually DECREASES N by 1. We apologize for any confusion this may cause.

This movie is also available in Quicktime format for the Macintosh.