---
title: Insights from Venable's Vault | Wayne H. Tuttle
description: Wayne H. Tuttle | A collection of key papers, course material, and documentation notes from Dr. Middlebrook and H. Dean Venable.
---

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*By Wayne H. Tuttle - February 10, 2020*

#### Why Conditionally Stable Systems Do Not Oscillate

Nyquist's 1933 paper on regeneration stated that a feedback control system could, at some frequencies, have 360 degrees of phase shift and more than unity gain without instability. At first glance it appears that this cannot be true. At these frequencies, the signal would progress around the loop...

[Read More](https://www.venableinstruments.com/venable-vault/why-stable-systems-do-not-oscillate)

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#### Venable Vault

Content from H. Dean Venable and Dr. R. David Middlebrook

to further education and research.  This content may not be used commercially 

#### About Venable

Venable provides scalable energy storage and power systems test solutions for precise voltage, current, and frequency measurements, partnering with engineers to ensure battery and power systems around the world will meet stringent field performance demands. 

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**Low-Entropy Expressions: The Key to Design-Oriented Analysis**

 20 January 2022 

](https://www.venableinstruments.com/venable-vault/low-entropy) [![The Two Extra Element Theorem](https://www.venableinstruments.com/hubfs/Bridged-T%20Filter_sm-1.jpg)

**The Two Extra Element Theorem**

 04 January 2022 

](https://www.venableinstruments.com/venable-vault/2eet)

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