Hardware Reference
In-Depth Information
C/Resistor Reference
If you're doing basic hobby electronics, you'll typically use resistors with four
color bands. The first three bands indicate resistance in ohms, according to
Table C-1
. The fourth band indicates tolerance, which will usually be gold (5%)
or silver (10%), but could also be brown (1%) or red (2%).
The
tolerance
of the resistor indicates the possible amount of variance be-
tween the indicated value and the actual value of the resistor. If no tolerance
is indicated, it's assumed that it's 20%.
Table C-1.
Basic four-band resistor reference
Color
First Band
Second Band
Third Band (Multiplier)
Fourth Band (Tolerance)
Black
0
0
x1
Brown
1
1
x10
1%
Red
2
2
x100
2%
Orange
3
3
x1K
Yellow
4
4
x10K
Green
5
5
x100K
Blue
6
6
x1M
Purple
7
7
x10M
Gray
8
8
White
9
9
Gold
5%
Silver
10%
To determine the value of a typical resistor, follow these steps:
1. Orient the resistor so that the gold or silver band is on the right side.
2. For the first band, get the first digit of the resistance value from
Table C-1
.
3. For the second band, get the second digit of the resistance value from
Table C-1
.
4. For the third band, get the multiplier from
Table C-1
.
