ELECTRONICS

B. D. McKay was a master of vacuum tube electronics, the precursor to today's solid-state circuitry.

	Electronic Symbols And Pictures An overview of schematic symbols for various parts, along with pictures of what they really looked like. Some of these parts predate solid-state electronics, such as the wire-wound resistor, and of course the vacuum tube!
	Radio-Receiver Diagram A diagram of a radio receiver from the days of vacuum tube electronics!
	Bicycle Diagram A look at all the parts of the bicycle and what they do.

The Electronics Papers

What started it? In 1979, B. D. came to visit my family in Kingsport, TN and that's about the time when the electronics lessons started for me. I can remember us going to a video arcade. I remember him playing a game in which the player looked through a periscope, but I can't remember the details. My enthusiasm for these games must have been apparent. (I was nine years old at the time.) Could my interest in video games have sparked him to begin to teaching me about electronics?

The first papers from 1979:

• Electricity, Electronics, Etc.
  From August, 1979.
• What Is Electronic Switching? And Who Cares? (Page 1)
• Basic Electricity (Page 2)
• Alternating Current (Page 3)
  The third picture under "Many Do", where it says "Toys, Games, Flashlights" is Hit and Missile.

The 1980s papers:

• A parts list
  Undated and cryptically labeled "ETCO", this list puzzles me. Although the paper is a form with a Candler address, this doesn't mean anything since BD was using this paper as late as 1984. (This paper is what most of the two-panel cartoons and handwritten bits of wisdom are on: the other side is blank. BD had boxes of it he used as scratch paper.) This may be an order BD put together for a mailorder catalogue when he was teaching me electronics in the 81-83 range. (ETCO is a mail-order electronics parts retailer, originally Electric Terminal Corporation est. 1947; at the time, in Hendersonville, mailorder was about the only way to get obscure parts, such as the tubes and tube sockets in this list..)
• An unlabeled schematic
  This is for a cigar-box power supply BD built for me. It had an old transformer he had gotten from somewhere which stepped down wall current to 6 volt AC. It also had a 6v DC battery pack in it. Eventually, this box got an AC to DC converter for the AC power source (not shown; it was a later addition) so I could use the wall current to power projects and not have to buy so many batteries! The top ("110V AC") is not just the box itself, but also a project: the red circles show where the project attaches to the power supply.
• A 4-Page Tech Book page 1
• A 4-Page Tech Book page 2
• A 4-Page Tech Book page 3
• A 4-Page Tech Book page 4
  Without question, this page demonstrates B. D.'s pedagogic trademark: plain language. His teaching most often took a precise, scientific definition and translated it into words normal people could understand.
• The Basis Of Electronics page 1
• The Basis Of Electronics page 2
• How Does A Buzzer or Bell Work?
• Dictionary page 1
• Dictionary page 2
• Dictionary page 3
• Dictionary page 4
• Explanation Sheet page 1
  These explanations are augmenting "Quiz page 2" below. I have always had trouble conceptually with the manipulation of orders of magnitude, and frequently make mistakes with decimal places and zeroes on the end without even realizing it. I did not, at the time, appreciate (or even understand) the feedback of making mistakes and having a teacher explain why I was wrong so that I could learn from it; the modus operandi at public school was the opposite, with the teachers presenting a certain amount of material and then giving a test, which was returned with wrong answers marked, while the class went on to the next unit of material. B. D. was more concerned with my learning than he was in how much material I was exposed to.
• Explanation Sheet page 2
• Fact (on magnetic fields) page 1
• Fact (on magnetic fields) page 2
  I wrote the "me, I'm not". At that time, I took everything quite literally and did not understand an ironic or rhetorical question of this nature.
• How A House Is Wired page 1
• How A House Is Wired page 2
• More Electronic Stuff page 1
• More Electronic Stuff page 2
• More Electronic Stuff page 3
• More Electronic Stuff page 4
• How An Oscilloscope Works
  Unfortunately we did not have one.
• Quiz page 1
  I did pretty good to know one of the four! I answered the third question with a picture of AC current, since I could not articulate what I was trying to say. Remember I had not even had algebra, let alone geometry or any kind of physics, in the 82-4 time period! (B. D. explained inverse feedback later. A "heterodyne" is used to mix signals together in a tube-based radio, and B. D. likely omitted it from his simplified explanations of how the transmitter combines microphone input with a modulator. RMS voltage is the average of the AC voltage from zero to peak on the sine wave; it's used to calculate the average amount of useful work an AC current can do. I am not sure how one derives a percentage from an average. You calculate it by sampling the positive and negative swings over time, squaring them, averaging them, and taking the square root so the average won't be negative.
• Quiz page 2
  I answered all the questions correctly in a fashion, except for #4 which was obviously wrong. (However, it's a normal error for me; given two alternatives like this, even knowing the right one would not prevent me from picking the wrong one without even realizing it. I likely knew the right answer.) I did not know the word "solenoid" for #2 at the time, or if I did I couldn't remember it. We had done the experiment in question (creating an electromagnet with a coil and battery, and watching a nail jump when the magnetic field was created; this is really the exact opposite of a solenoid which moves metal in a coil to create current).
• Resistor Color Code
• Review page 1
• Review page 2
  On the back of this page is the caution for dry cells.
• A Caution For All Dry Cells
• Some Random Thoughts page 1
  Although this started out as a collection of thoughts on different topics, other than the first item they all relate to electronics and therefore it has always been kept with the electronics papers.
• Some Random Thoughts page 2
• Some Random Thoughts page 3
• Reception Ratings
• Sheet Of Electronics Facts To Understand And Remember
• Simplified Diagram Of Standard 5-Tube AC Radio
• 5 Tube AC Radio
• 5 Tube AC Radio (back of page)
• (Solder) Facts About Soldering
• (Solder) Some Soldering Facts
• (Solder) Soldering Iron Tips
• (Solder) Fact
• (Solder) Illustration
• Simple Continuity Checker
  This is the "over" side of the (Solder) Illustration page.
• Schematic Symbols
• Troubleshooting Electronics page 1
• Troubleshooting Electronics page 2
• How Does A Tube Work page 1
• How Does A Tube Work page 2
• Test
  I made a perfect score on this test. Most of these questions were easy, even at the time (before I had a formal science class) since a speaker couldn't push air in a vacuum, fire could not use oxygen, and similarly the oxidation chemical reaction could not occur without oxygen. Number 5 was something we'd talked about (wind resistance, or drag, increases, but not air pressure). I do remember that I took a guess on #6. The distinction between "in" and "into" was a pet peeve of BD's. I liked it for the same reason I liked the doctor in his Hickory, Dickory, Doc cartoon; I liked absurd images such as loading a gun with ducks and shooting them into the pond.
• Test page 2
  Concerning #8, I believe this refers to the question in the On Aviation section, "By The Numbers' Problem". At the time, I did not notice that this was a test I was supposed to complete and hand in.
• The Transmitter page 1
• The Transmitter page 2
• The Transmitter page 3
• Variable Resistor
• What Things Are Called
  Although "integrated circuit" appears in this list, I do not believe B. D. ever worked with them. He likely had in mind operational amplifiers, etc and not digital electronics.
• What's A Wafer Switch?

Ohm's Law: Resistor Color Code Card front
Ohm's Law: Resistor Color Code Card back
The card is old, and one B. D. already had at the house in Hendersonville and had likely been around for many years.

Schematic Diagram from Dec. 1957.
This would appear to be a diagram for how to construct an analog reverb sound effect.

Hit and Missile
Background information.

Electronics Artifacts From Hendersonville

The following are some of the artifacts that have been preserved from Hendersonville. Many of these are ones B. D. and I would have worked with together.

A dime has been placed by the components for scale. One of the most notable features of tube electronics is the amount of power that was used. All components had to be heavy-duty to withstand the wear and tear of the electrons coursing through them. The switch to low-power transistorized electronics meant that other components could also shrink, because they had to handle much less power than before.

	Electronics Artifacts This is a sample of some of the more representative of the electronics parts B. D. had in Hendersonville.
	Electronics Artifacts: Big Resistors Right to left: the wafer capacitor discussed later, a 10-ohm resistor, and another capacitor rated at 600 volts.
	Electronics Artifacts: Box And Fuzzy Capacitor The diodes no longer survive, but this box had two diodes (rectifier is another word for diode) in it. Interesting to see the RCA box and stock number. The white thing is some sort of capacitor.
	Electronics Artifacts: Top Hat Transistor And Others From clockwise, starting at the dime, is: A wafer-style capacitor. Two other capacitors. The plastic container for the transistor. A top-hat style transistor (these were used for a while before the tiny transistors I knew were in use). A resistor (interesting example of a large resistor with a high power capacity, with the color code still visible).
	Electronics Artifacts: Tube Mounts These are three tube mounts. Tubes were prone to failure, so these mounts would be wired into the circuit and a tube plugged into them. When a tube failed, it could be unplugged and a new one plugged in.
	Electronics Artifacts: Wiring Post This is very likely one of the wiring posts which B. D. used to teach me how to solder.
	Electronics Artifacts: Small Tube B. D. and I never progressed far enough for me to actually build tube radios. He did, however, have a few extra tubes around in his supply bin. This is a small one. Tube with box Box (one side) Box (other side) Tube Tube (Brightly Lit)
	Electronics Artifacts: Large Tube This is a larger tube which did not have a box. Tube Closeup On Glass Closeup On Base
	Electronics Artifacts: Suspended Parts Of A Tube In Glass This was one of B. D.'s favorites, a tube and its parts encased in glass. Tube Parts In Glass Etched Signature

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