RESISTORS (R)

RESISTORS obstruct the flow of electric current. They have no polarity (+/-) and can be connected either way in a circuit, so you can't really mess them up. For most of my projects, they are used to control the pitch of the oscillator. The resistance value is measured in ohms. The tolerance is the degree of sway from the value listed. Electronics aren't perfect.

You can identify the resistance and tolerance value from the color bands on the side of a resistor. The first band represents the first digit of the number, the second band represents the second digit, the third band represents the multipler, and the forth band is the tolerance value. For example, a resistor whose first band is yellow, second band is violet, third band is orange, and last band is gold would have a value of 47K with a tolerance of +/-5%.

1. FIRST DIGIT
2. SECOND DIGIT
3. THE MULTIPLIER
4. THE TOLERANCE

Here is a chart I made which explains what each color means. The colors are arranged chromatically, with darker colors having the lowest value and lighter colors have the highest value. Metallic colors go into decimals, with gold being the best, and silver being second.
















Resistors come in really strange values because they work within the tolerance percent ranges, because of the these ranges there isn't a need to make every value of resistor. There are two different series of resistors, but they both repeat in multiples of 10 for higher values.

The E6 series has six values : 10, 15, 22, 33, 47, 68
The resistors from this series all have a 20% tolerance value.
The values go up roughly 50% between each increasing value.

The E12 series has twelve values : 10, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82
The resistors from this series all have a 10% tolerance value.
The values go up in smaller increments in this series to compensate for the lower %.

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This is the symbol for another kind of resistor, a variable resistor or POTENTIOMETER. Really, this is just a knob that you can turn to change the amount of resistance going through a circuit. Different types of potentiometers have different ranges, but they are rated according to the maximum potential value.

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