There are no electrons by Kenn Amdahl

• No one really understands electricity. But no one wants to admit it. Once I realized that truth, it became easy to learn about electricity.
• Just about every area of human activity, from sports to medicine to electronics, has its own specialized vocabulary, it’s own “little language”. These words and phrases are the “jargon” of the activity.
• Remember that most education is based on the premise that “speaking the language is more important than having something to say”.
• As a practical matter, jargon serves two rather wonderful purposes. First, it’s a shorthand for the people who understand it. [...] It’s poetry. Unless, of course, you don’t understand the vocabulary. Which brings up the other wonderful thing about jargon: It can be used to confuse and exclude people who are not members of the club. I call this “The Pig Latin Principle”.
• Perhaps eighty-five percent of the task of learning electronics is simply remembering about two dozen neat words. And there are, indeed, wonderful words, masterpieces of jargon.
• Like charges repel each other. Opposites attract.
• The truth is that electricity always moves from negatively charged things toward positively charged things.
• In static electricity, things with the same kind of charge (“like charges”) will repel each other, while things with opposite charges (a positive and a negative) will attract each other. And when electricity, whatever it is, moves, it always moves from negative things toward positive things.
• Man thinks in analogies, in fables, in parables. That is, he compares things he doesn’t understand the things he does. This makes facts understandable and easy to remember.
• We take subtle, confusing or complicated phenomena and translate them into simple little picture stories. These “scientific models” are useful teaching tools and handy communications aids, but they are also dangerous, because no model is perfect.
• When we use an analogy or model too much we risk losing sight of the reality that the model tries to represent.
• Scientific thought has always been limited by the imperfections of its various analogies.
• Voltage is the force that pushes electricity, the reason it moves, or wants to move.
• Voltage is measured in units called volts.
• Voltage is sometimes called “potential” because, whenever there is voltage, there is the potential for electricity to move.
• Voltage is the force behind electrical movement. Current is the movement of electrons through something. Electricity can have both voltage and current at the same time, and usually does. We measure voltage in volts and current in amperes or amps.
• Since everything electricity goes through has some resistance, everything heats up, at least a little.
• The fact that electricity always produces heat when it moves through resistance is extremely handy.
• If an electrical device is producing heat, some current is probably moving through some resistance.
• Heat produced by resistance is one of the most common and valuable products of electricity. Unwanted heat is also one of the principal causes of equipment failure.
• To get current to flow, there has to be a return path, a closed loop, a “circuit”.
• We have known for a long time that electrical current is always surrounded by a magnetic field. We also know that whenever a magnetic field moves past a conductor, it creates an electric current.
• The most important thing to remember is this: Self-induction opposes any increases or decreases in current.
• You can think of capacitance as both the ability of something to store a charge and the attraction of a current to a place where it can’t get through. If you direct a current onto something that has lots of capacitance, but no electrical path out the other side, current will flow until that something becomes full. Once it’s full, or charged completely, no current will flow.
• AC is better than DC for long distances because of self-induction.
• Direct current travels in one direction. Alternating current reverse direction rhythmically. These reversals are measured in “cycles per second” also known simply as “cycles”. Each cycle represents a round trip, and includes two current reversals.
• Generators produce DC, alternators produce AC.
• The part of a generator or alternator that spins is called the “rotor”. The part that is stationary is called the “stator”. [...] The electromagnet may be either on the stator or the rotor. The electromagnet itself is called the “field” and the coil of wire you’re trying to produce electricity within is called the “armature”.
• Life would be a lot different if [electrons] didn’t get angry and hot when forced to move through resistance. If an electrical device is supposed to produce heat, there’s probably a high-resistance heating element lurking in it somewhere.
• Life would also be a lot different if every electrical current wasn’t surrounded by magnetism. Most of the electrical devices that move in one way or another use an electromagnet to do the moving. Think about that: if an electrical device is moving, an electromagnet is probably at work.
• Magnetism is the only practical way to get much physical motion out of electricity.
• If it turns or spins, there is probably an electric motor turning it, working because of magnetism.
• Heat and magnetism are the main links between the world of the [electron] and the world of the humans.
• Except for a few wonderful by less common tricks, the final product of all electrical devices involves either magnetism, heat, or phosphorescence.
• “Components” is a fancy word that means “little electrical parts”.
• To determine the total amount of resistance of resistors in series, just add them up.
• If all your resistors are the same size, the more of them you put into a circuit parallel to each other, the less total resistance you’ll see in your circuit.
• The total resistance of resistors in parallel will always be less than the smallest resistor.
• If you add a capacitor in parallel to another, you effectively increase the surface area. You know that more surface area means more capacitance.
• When you put capacitors in series you are effectively increasing the distance between the plates. Since increasing the distance between the plates decreases the amount of capacitance, putting capacitors in series actually decreases the total capacitance.
• To increase a coil’s self-induction, add more loops of wire, squeeze the loops together tightly, or add an iron core.
• When we want more self-induction in a circuit, we add a coil of wire.
• Maybe you want to protect your other components from a violent surge of current. No problem. Add a coil. Surges of current are the things that coils stop the best.
• Soils tend to stabilize the current in a circuit. They tend to oppose any change in the status quo.
• Coils that are used to eliminate AC above a certain frequency are called “chokes”.
• Inductance is measured in “henrys”.
• Coils in parallel act like resistors in parallel.
• When two coils are placed close to each other for the specific purpose of letting the current in one induces a current in the other, we call the thing a “transformer”.
• Transformers can be used to connect two circuits together when one might have some DC which you want to isolate from the other. Only the AC will induce current. Whatever DC might have been in the first circuit will be left behind, while the AC continues onward.
• If you send a pulse of electricity through a closed loop of a superconducting material, it will keep going “round and round” forever.
• Electricity moves across a P-N junction in the “N” to “P” direction fairly easily. It does not move the opposite direction easily at all. This is why a P-N junction diode works.
• A transistor is a sandwich made of “P” material and “N” material.
• A triode is just a diode with a metal screen or grid between the cathode and the plate. By itself, the screen has no effect on the circuit. [Electrons] stream right through it. However, a slight negative charge on this grid will stop the current.
• Electrical amplifiers don’t really increase anything. They are devices in which a small current or voltage controls a larger voltage or current.
• That’s what a transistor is, really. A variable resistor. Transistors can be used as either little electronic switches or as amplifiers.