Christophe P. Basso has written a new book: Linear Circuit Transfer Functions—An Introduction to Fast Analytical Techniques.

A nonlinear parity–time-symmetric circuit is used to enable robust wireless power transfer to a moving device over a distance of one metre without the need for tuning.

Commercial curve tracers have existed for decades. But designers without access to one can create a simple circuit that uses a function generator and oscilloscope to generate JFET transfer and ...