In lecture TDT06, we explore how to analyzer a transmission line in a circuit with a pre-existing charge. This material is important in the world of high-speed digital electronics, where logic pins that suddenly switch low or high can propagate peculiar transients on signal lines … even if they are only used to load an initially-charged line.
As a side note, my first preparation of this lecture led to the four basic equivalent circuits for time-domain transmission lines, summarized in the figure on the left. These useful equivalents (specifically the general equivalent circuit) had never, to my knowledge, been reported in a textbook or subject paper before. But the GT students found them particularly useful, especially for working the infamous sequencer problems.