Tube Electronics

MIT IAP 2025

Hi.

Welcome to the homepage for the 2025 IAP offering of 6.S917, "Tube and Early Transistor Circuits."

Syllabus/info is here. Office Hours Calendar is below and all the course material will appear below that in reverse chronological order as it is released.

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Week 1

• Lecture 1: Background
  • Technology: The Emergence of a Hazardous Concept by Leo Marx
• Lab 1: Electromechanical Amplifiers
  • Claude Shannon's 1938 Thesis linking logic to relays
  • Konrad Zuse's Early Computers
• Lecture 2: Detectors and Nonlinearity
  • Early Radio Wave Detectors (V.J. Phillips)
  • From Branly Coherer to Chua Memristor (Chap 1 from Fractional Dynamics, Anomalous Transport, and Plasma Science)
  • Electrical conductivity in granular media and Branly's Coherer: A Simple Experiment
  • "The Italian Navy Coherer Scandal Revisited" by Probir K. Bondyopadhyay
  • "The Dynammo and the Virgin" Chapter from Henry Adams' The Education of Henry Adams
  • The Future Eve by Auguste Villiers de'Isle-Adam (in French Sorry, English translation somehow not out of copyright...just view it in Chrome and use Google to translate the page, though.)
  • Edison's Conquest of Mars by Garrett P. Serviss
  • The Saga of the Vacuum Tube (chapters 1-2) by Gerald F.J. Tyne
• Lab 2: Germanium FM Detector

Week 2

• Lecture 3: Diodes and Triodes
  • Diode Applications: (Power supplies, voltage regulators & limiters)
    • Tube Power Supplies usually used a center-tapped transofmer and dual triode tube such as the Type 80
    • Alternatively later they would often use something like the 5Y3GT
  • Early triodes were relatively simple, for example the Type 26
  • Later triodes got more complicated such as the 12AU7A medium-mu double triode, the 12AT7 high-mu double triode, or the 6J6 common-cathode twin triode which we'll use in Lab 4
  • The 1951 Film Adaptation of A Streetcar Named Desire. At 33:31, Vivienne Leigh turns ona tube radio and it starts to play music after < three seconds. Then does that again at 38:20. The rest of the movie is great, though, and a classic.
  • Triode Equation Derivation (great, great site)
  • Article About Magnetic Amplifiers (from Lecture)
• Lab 3: Vacuum Fluorescent Displays
• Lecture 4: Designing with Tubes
  • 866A Mercury Vapor Rectifier
  • 822 High-Power Triode
  • Chapter 1 of Designing Valve Preamps for Guitar and Bass, Second Edition by Merlin Blencowe. Really great book if you want a tube book, this is the one to buy
  • Article on Vibrator Power Supplies
• Lab 4: Tube Audio Amplifier

Week 3

• Lecture 5: Tetrodes, Pentodes, and Other Things
  • "Dependence of the input impedance of a three-electrode vacuum tube upon the load in the plate circuit" Scientific Papers of Bureau of Standards (1920) by John M. Miller (of Miller Capacitance Fame)
  • Type 24A Tetrode
  • 12AU6 Pentode (a standard normal voltage pentode)
  • 12CN5 Pentode (a later, low-voltage (12V) pentode designed for car usage)
  • Man of High Fidelity: Edwin Howard Armstrong. Out of print since 1969...copy included here
  • "Mesure en valeur absolue des périodes des oscillations électriques de haute fréquence" by Henri Abraham, Eugène Bloch 1919 J. Phys. Theor. Appl.
  • "100 years of multivibrator-history, circuits, and mathematical analysis" Wolfgan Mathis 2019
  • Good paper on oscillator theory (also cites a lot of papers so good jumping off point)
  • Cool paper linking some interesting concepts of oscillation to biology and engineering. Another good paper with lots of juicy references in it for further reading.
• Lab 5: Oscillators, Pentodes
• Lecture 6: Further Circuits
  • Somebody rebuilt the first flip-flop (Jordan-Eccles Circuit) using period-accurate tubes
  • "Stabilized feed-back amplifiers" by H.S. Black Electrical Engineering vol. 53, pp. 114-120, Jan. 1934
  • Very Nice Writeup on Basic Concepts in Automatic Gain Control
  • 1940's Western Electric Newsreel "Vacuum Tube Electronics at Work"
• Lab 6: An Operational Amplifier

Week 4

• Lecture 7: Solid-State Triodes
  • Technical Note by Bob Widlar (famous EE) on Transistor Design
  • Note from Motorola on possible future with transistor supplanting tubes
  • Raytheon Transistor Applications
  • Great early book on "Transistor Circuits" by Turner
  • Really fascinating documentary on Japan's electronics industry buildup...which replaced a huge portion of the US share. Japan's share has in turn largely been replaced by China/Taiwan since this documentary was written. Also super weird, but the background music starting at 0:34 sounds like "Orinoco Flow" by Enya right? I'm not crazy about that?
  • "The Long Corridor", 1955 Documentary by Zenith on their Solid State Research
  • 1978 Documentary on the Closing of the last major Zenith Assembly plant in the US. Note they were still largely assembling by hand up until this point (the last manufacturer to be doing so at any significant scale). The focus on this piece is the socio-economic angle of larger trends in US labor at the time.
  • Western Electric Site. Last state-side maker of vacuum tubes (300-B, about $700 a piece)
  • Reflection article on ENIAC
• Lab 7(last): Solid State Triode Amp

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Calendar