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The Electron Theory

by Mike Fratus,

{This is a limited-content document that will be used in my upcoming Tube Amp Class and Book.}

I remember that when I was little, I wondered how stuff worked, and had wild ideas about how things worked without any knowledge of even what was inside things. It took many years to get around to electronic things, and delving into how they worked.

So, I am attempting to pass on what I had to learn to understand electronics the way I do, without all the false starts and side trips.

Atoms and their parts

Atoms are the building blocks that make up everything we can see and a lot of things we can't. But even the atoms are made up of smaller building blocks. Every atom has at least one proton and one electron. The element Hydrogen has only these two particles. These two fundamental particles are the charged particles of the atom. The proton has a positive charge, and the electron has a negative charge.

Atoms are also known as "The Elements." You have heard their names before, I'm sure. Most science classrooms have the chart called "The Periodic Table" posted somewhere. The table starts with Hydrogen, Helium, Lithium, and so on, in the order of how many protons they have. Hydrogen has one, Helium has two, Lithium has three. They also have more-or-less the same number of electrons, as well. The third particle, the Neutron, has properties that we won't consider important for our subject here. But it is necessary. It sort of balances the atom, because of what the electron does in its very important job. More about that in a minute.

The universe is an illusion - really!

What we see as we look around is not really the way things are. What we are really seeing when we look at any object is actually the fields and forces between atoms. Atoms themselves are vanishingly small. The distance between atoms are enormous compared to the atoms themselves, but that just shows how important these forces and fields of energy are to our universe.

Electrons and their job

Protons and neutrons are stuck in the center of the atom, called the Nucleus. Electrons, however, are free to come and go. They spend most all of their time orbiting the nucleus, which is their job - orbiting some nucleus somewhere. They can jump to another atom, and start orbiting it, or keep going, hopping from atom to atom, as they are attracted or pushed out. That is their job. They represent the energy content of the atom, and define bonds between atoms that they visit regularly. The forces that bind atoms together into the things we see and touch and use are carried by the electron. They are important.

Conductors and non-conductors

Electrons travel in a most peculiar way. Each atom has a "normal" number of electrons that orbit it. They also have something called Valence that is a sort of "fudge factor" character of the atom. It means that atoms will accept or donate a number of electrons. This is important because it also determines which atoms the electrons will travel to or come from.

If another atom will accept electrons or provice them, it is considered a Conductor. If it will neither accept or provide electrons, it is considered an Insulator. We use these properties to control where electrons go, and where they don't.

Two ways electrons travel

1. Electrons go hopping from atom to atom according to whether there is a "hole" for it to move to. A hole is where an electron CAN be, but is missing. They can also be inclined to move when an extra electron arrives from another electron, and the valence number for that atom is already reached. So one of the electrons has to move on - it does not matter which one - but there are only so many electrons allowed orbiting an atom.

2. Electrons can become "mobile" when they have too much energy to stay in orbit around an atom. Instead, they act like a swarm of insects, looking for a place to land, where there is an electron hole.

Those are the two major modes of movement. The first way happens inside metallic wires and other conductive substances. The second way happens in a air around a conductor or in a vacuum around a conductor.

What is a battery, then?

A battery is really an electron pump. One terminal "wants" electrons (by having holes), and the other terminal provides electrons. In what we will call a "closed circuit," the electrons come out one terminal, travel through the circuit, and return to the battery at the other terminal. Which is which is a matter of a very short sentence, but tends to turn common thinking on its head because it is the opposite of conventional thinking. Here's how:

Electrons are provided by the Negative terminal of a battery, and return to the Positive terminal.

"Conventional" current flow says that "electricity" comes out the Positive or Plus terminal and travels to the Negative or Minus terminal. But when you see how tubes work, you will understand why things are really different.

Note: This is an appropriate place to define two terms: Voltage and Current. The way I learned it seems to work: Voltage is how badly electrons want to get somewhere; Current is how many want to travel at the same time. (That is why the cables on your car battery are so thick... many electrons need to travel at the same time to turn the starter motor. That is a lot of current.)