User manual

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A jumper wire is also included in the learning package. It is used to build short connecting bridges to which
the contact rows on the breadboard are connected. Cut the wire with a wire cutter to the appropriate length,
as described in the individual experiments. We recommend cutting the wires slightly at an angle, so that they
form a wedge-shape, which allows you to insert the wires into the breadboard more easily. Remove the
insulation at both ends over a length of roughly half a centimeter.
2.1.3 Resistors and colour codes
Resistors are used in digital electronics primarily to limit the current at the ports of a microcontroller as well
as series resistors for LEDs. Resistance is measured in Ohm. 1,000 ohms are one kilo Ohms, and is
abbreviated kOhm.
The resistance values are indicated by colored rings on the resistors. Most resistors have four such colored rings.
The first two colored rings stand for numerals, the third is a multiplier and the fourth is the tolerance. This
tolerance ring has usually a gold or silver color - these are colors you will not find on the first rings, so the
reading orientation becomes clear. The tolerance value itself has barely any significance in digital electronics.
Resistance value in Ohm Colour
1. Ring
(Tenth)
2. Ring
(Ones)
3. Ring
(Multiplier)
4. Ring
(Tolerance)
Silver
10
−2
= 0.01 ±10 %
Gold
10
−1
= 0.1 ±5 %
Black
0 10
0
= 1
Brown 1 1 10
1
= 10 ±1 %
Red 2 2 10
2
= 100 ±2 %
Orange 3 3 10
3
= 1,000
Yellow 4 4 10
4
= 10,000
Green 5 5 10
5
= 100,000 ±0,5 %
Blue 6 6 10
6
= 1,000,000 ±0,25 %
Violet 7 7 10
7
= 10,000,000 ±0,1 %
Grey 8 8 10
8
= 100,000,000 ±0,05 %
White 9 9 10
9
= 1,000,000,000
Tab. 2.1: The table shows the significance of the coloured rings on the resistors.