Phillip H. Smith: A Short Biography

Phillip H. Smith (April 29, 1905 – August 29, 1987) was an American electrical engineer who made significant contributions to the field of RF engineering. He is primarily known for his work on transmission line theory and impedance matching. Smith's research in the 1930s while working at Bell Labs led to the development of the Smith Chart, which is a graphical representation of complex impedance values.

The Smith Chart is a polar plot that helps engineers analyze and design RF circuits, such as impedance matching networks and transmission lines. It provides a visual representation of impedance and reflection coefficient values, allowing engineers to easily determine the impedance characteristics of a system and make necessary adjustments to optimize performance.

The Smith Chart has become an essential tool in RF engineering, and it is widely used in various applications, including antenna design, RF filter design, and microwave circuit design. It simplifies calculations and provides a intuitive way to understand and manipulate complex impedance values.

Here is "The Oral History: Phillip H. Smith," and interview by Engineering and Technology History Wiki. This January 1939 issue of Electronics magazine might be the first appearance of the most recognized version of the Smith Chart.

This content was generated by primarily with the assistance of ChatGPT (OpenAI), and/or Gemini (Google), and/or Arya (GabAI), and/or Grok (x.AI), and/or DeepSeek artificial intelligence (AI) engines. Review was performed to help detect and correct any inaccuracies; however, you are encouraged to verify the information yourself if it will be used for critical applications. In all cases, multiple solicitations to the AI engine(s) was(were) used to assimilate final content. Images and external hyperlinks have also been added occasionally - especially on extensive treatises. Courts have ruled that AI-generated content is not subject to copyright restrictions, but since I modify them, everything here is protected by RF Cafe copyright. Many of the images are likewise generated and modified. Your use of this data implies an agreement to hold totally harmless Kirt Blattenberger, RF Cafe, and any and all of its assigns. Thank you. Here is Gab AI in an iFrame.

AI Technical Trustability Update

While working on an update to my RF Cafe Espresso Engineering Workbook project to add a couple calculators about FM sidebands (available soon). The good news is that AI provided excellent VBA code to generate a set of Bessel function plots. The bad news is when I asked for a table showing at which modulation indices sidebands 0 (carrier) through 5 vanish, none of the agents got it right. Some were really bad. The AI agents typically explain their reason and method correctly, then go on to produces bad results. Even after pointing out errors, subsequent results are still wrong. I do a lot of AI work and see this often, even with subscribing to professional versions. I ultimately generated the table myself. There is going to be a lot of inaccurate information out there based on unverified AI queries, so beware.

Electronics & High Tech Companies | Electronics & Tech Publications | Electronics & Tech Pioneers | Electronics & Tech Principles | Tech Standards Groups & Industry Associations | Societal Influences on Technology