 Resistors
Crib Sheets
Hit = 104

DigitalDan

Contact Site
Resistor Codes
Resistor Colour Codes Note If there is only 3 colour bands, the missing one will be band d.
The absence of band d implies the resistor accuracy is ±20%

1. Write down the digit provided by the colour of band a
2. Write down the digit provided by the colour of band b
3. Write down the multiplier provided by the colour of band c
4. You have found the resistance in Ohms
5. If band d is present, this indicates the accuracy of the component.
abcd 0 0 x100Ω 1 1 x101Ω ±1% 2 2 x102Ω ±2% 3 3 x103Ω 4 4 x104Ω ±5% 5 5 x105Ω 6 6 x106Ω 7 7 x107Ω 8 8 x108Ω ±10% 9 9 x109Ω

Three Digit Resistor Number Codes 1. Write down the first 2 digits (shown as a on the diagram)
2. Write down "x10"
3. Write down the x10 multiplier given by the third digit
4. This is the resistance in Ohms

Here are some examples
234 = 23 x104Ω = 230kΩ
170 = 17 x100Ω = 17Ω
135 = 13 x105Ω = 1.3MΩ

Number and One Letter Resistor Codes 1. Write down all digits before the letter. (If there are no digits before the letter then write "0")
2. Write down a decimal point "."
3. Write down all the digits after the letter
4. Look the letter up in this table and write down the answer