Pen and Ink of Yin-Yang Smith Chart

This was done while I was a graduate student at MIT studying Microwave Engineering. If I did this today it would have been done with something like Adobe Illustrator, but those programs did not exist in 1975 or 1976. The Smith Chart is used to plot amplitude and phase reflections of microwaves in complex coordinates. They were a thing of beauty to techno-nerds and I was quite expert at them.

Pen and Ink of Smith Chart
Pen and Ink of Yin-Yang Smith Chart