**Engineering and Design lecture series**

Loe Feijs of the Technical University of Eindhoven describes his work simulating electronic circuits with CA rules.

Loe explores the expressive power of CAs as an alternate basis for electrical engineering. As his first goal, he has designed several CA systems that attempt to emulate an RC phase-shift oscillator, with the assumption that if this is possible, more complex circuits will also be possible.

In his first attempt, each cell is assigned a voltage value. Rules define a diffusion and flow of voltage. This system was then extended to 2D with a graphical grid-based circuit specification (made using MS Paint!) and appropriate 2D rules. This system was successful at modeling a simple resistive system like a voltage divider. However, problems arose when trying to add a model for capacitor plates.

His second attempt utilized block CAs, and like the first used special colors to position the ground plane and input-level voltage, as well as to overlay voltmeters and ammeters. This method was again successful in modeling voltage dividers, and could also model capacitor plates using a special, larger rule. However, this model failed when trying to model FETs, but was instead able to model beam-deflection transistors, also known as vacuum tubes. This allowed the successful modeling of a phase-shift oscillator.

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