This was a training topic by AC4HH for the YL Net
YL Lesson: Resistors, Capacitors, and Semi-Conductors
Tonight we’re going to go over the exercise about identifying resistors in your booklet that came with the soldering kit. But first, I thought I’d define some of the components in the kit.
First is the RESISTOR. The resistor as defined in the soldering practice kit is a “component used to control the flow of electricity in a circuit. It is made of carbon.” Definition from the Internet is: The resistor is a component that resists the flow of current. It is a passive device that doesn’t do anything actively in the circuit, but resistors allow you to have the current and voltages you want in your circuit. It goes back to Ohm’s Law beginning with the formula: I=E/R. Where (I) is the current – sometimes given as (P) for power – equals voltage (E) or (V), divided by resistance (R). The current is the amount of charge flowing through a certain point, and the resistor slows down the flow of the current or charge.
Now let’s talk about CAPACITORS. Our soldering kit booklet defines a capacitor as an electrical component that can store electrical pressure (called voltage) for release when needed. The Internet states that capacitors are energy-storing devices similar to a battery except the capacitor releases its energy much more rapidly. For example, a capacitor if fully charged, can release its energy all at once, such as in a flash bulb. You can charge a capacitor simply by wiring it up in an electrical circuit. When you turn on the power, an electrical charge gradually builds up on the plates – it contains a positive plate and a negative plate. Capacitors are often used as timing devices.
The last component for today is a SEMI-CONDUCTOR. Semi-conductors are like voltage regulators. They are made of a material (often silicon) that has an electrical conductivity falling between that of a conductor –metals, such as copper or gold and an insulator such as glass. Probably you have seen power poles with glass insulators near the top. The semi-conductor conducts current, but only partially.
Quick review: A Resistor resists the flow of current, allowing you to set the current and voltage you want in your circuit.
A Capacitor stores electrical current and can release it much more rapidly. It contains a positive and a negative metal plate.
A Semi-conductor acts as a voltage regulator. It conducts current, but only partially.
Now, let’s look at page 3 of the soldering kit booklet and do the exercise. You will notice that the sketches of the resistors on page 3 give the colors of each band. The chart on page 2 gives the value in Ohms for each color with a multipler. So for each color band, pick out that color from the chart and write its value in on page 3.