High Power Amp Teaching Resources
www.kitronik.co.uk/2143
Resistor Values
A resistor is a device that opposes the flow of electrical current. The bigger the value of a resistor, the more it
opposes the current flow. The value of a resistor is given in (ohms) and is often referred to as its ‘resistance’.
Identifying resistor values
Band Colour
1st Band
2nd Band
Multiplier x
Tolerance
Silver
100
10%
Gold
10
5%
Black
0
0
1
Brown
1
1
10
1%
Red
2
2
100
2%
Orange
3
3
1000
Yellow
4
4
10,000
Green
5
5
100,000
Blue
6
6
1,000,000
Violet
7
7
Grey
8
8
White
9
9
Example: Band 1 = Red, Band 2 = Violet, Band 3 = Orange, Band 4 = Gold
The value of this resistor would be:
2
(Red)
7
(Violet) x
1,000
(Orange)
= 27 x 1,000
=
27,000
with a 5% tolerance (gold)
=
27K
Resistor identification task
Calculate the resistor values given by the bands shown below. The tolerance band has been ignored.
1st Band
2nd Band
Multiplier x
V
alue
Brown
Black
Yellow
Green
Blue
Brown
Brown
Grey
Yellow
Orange
White
Black
Too many zeros?
Kilo ohms and mega
ohms can be used:
1,000 = 1K
1,000K = 1M
