Resistors are electrical components that exhibit a specific amount of resistance on a circuit. The higher the resistance (measured in ohms) the lower the current will be in the circuit. Resistors are used to limit circuit current and as voltage dividers. Resistors come in a range of values and power ratings. The 1/4W type work well for diy. Resistor types include: carbon composition, carbon film, metal film, wire-wound, etc. Metal-film resistors are more temperature stable than carbon types and come in tighter tolerances. Click the color buttons to set resistor bands, then click the "Show" button to display the value. If the value is a standard selection then the value display box turns light green, if not it turns yellow.
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5% Tolerance Resistors
Standard 5% Values
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1% Tolerance Resistors
Standard 1% Values
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| Resistors with a 5% tolerance are usually carbon film or carbon composition type. The first two bands are resistance value bands and the third band is the multiplier band. The gold tolerance band tells you this is a 5% tolerance resistor. For example a 10K 5% resistor can vary in initial value between 10.5K and 9.5K. The multipler band tells you how many zeroes to add to the first two numbers to arrive at the coded value. For example brown, black, yellow means 1, 0 and four zeroes 0000 or 100,000 ohms (100K). A gold multiplier band means to multiply the value by 1/10th. It is seen on low value resistors. I suggest you don't buy resistors with less value tolerance than 5%. | Metal film resistors have tighter tolerance (2%, 1% and better) and much better immunity to value drift due to temperature variation. You can always replace a 5% carbon film resistor with the same (or closest) value 1% metal film resistor and improve your circuits immunity to temperature related drift. The tolerance band is brown indicating 1%. The first three bands are value bands and the fourth band is the multiplier band. The multipler band tells you how many zeroes to add to come up with the final resistance. For example brown, black, black, brown means 1, 0, 0, and one more zero 0 or 1000 ohms (1.0K). A gold multiplier band means multiply the number made up by the value bands by 1/10th. |