Triode Common Cathode Stages, the Oracle Equation, and Theodosian Objections

For those readers interested in tube amplification, this article proposes a simplified equation of what might appear to be multiple mathematical factoids into a single concept, intended to help characterize and understand triode circuits.

- Christopher Paul

About the Author

Christopher Paul was born in the US the year before the Nobel prize was awarded for the invention of the transistor, the development of which he claims no credit for. His love of music from an early age led to some puzzling experiments with musical instrument amplifiers, and from there to an interest in electronics. Chris finds it interesting to delve into relatively simple circuits and to investigate and write about aspects of their performance that are little known or appreciated. He enjoys deriving equations that can be used to evaluate and design them, although he admits to being in therapy for this. Chris has worked for companies whose products are in the fields of communications, electronic article surveillance, and enterprise hand-held computers. He holds two M.Sc. degrees in electrical engineering from Brooklyn Polytechnic (now part of New York) University.

With a title like this, you're probably wondering what you're in for. My motivation for writing this article is to propose a simple, straightforward means of enhancing the understanding of specific triode circuits and to settle certain controversies, some of which are well-known and long-standing. I hope you'll find this approach to be a mixture of simplicity, elegance, and technical accuracy. For completeness, I'll also cover disagreements with some of the conclusions it reaches.