---
title: The Two Extra Element Theorem
description: The Two Extra Element Theorem by Dr. R.D. Middlebrook.
image: https://www.venableinstruments.com/hubfs/Bridged-T%20Filter_sm-1.jpg
---

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## The Two Extra Element Theorem

*By Dr. R. D. Middlebrook - January 04, 2022*

Abstract

The Two Extra Element theorem (2EET), a logical extension of the single EET, enables a transfer function to be assembled, essentially in final form, from separate calculations on a circuit model that is simpler by the absence of two elements.  The 2EET provides not only a potentially shorter, simpler, and easier analysis method, but also contributes a Low-Entropy Expression in which the ordering and grouping of terms contains useful design-oriented information.  As an example, the 2EET is employed in design-oriented analysis of a bridged-T filter.

[R.D. Middlebrook, “The Two Extra Element Theorem”, *IEEE Frontiers in Education*, *Twenty-First Annual Conference*, Purdue University, Sept 21-24, 1991, pp. 702-708.](https://www.venableinstruments.com/hubfs/The%20Two%20Extra%20Element%20Theorem_Middlebrook.pdf)

 

 

 

 

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