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Electronic circuit theory - Understanding resistors

The resistor is arguably one of the most important components in an electronic circuit. Without them then many circuits would not work and components could be destroyed. It is therefore essential to understand what a resistor is, why it is needed and how to calculate the correct resistor. If not then you may find components going up in smoke as shown in this video.

resistor colour code example

The basic through-hole resistor is shown in the diagram above. This also shows the 4-colour resistor color code. See the resistor electronic component reference guide for details of how the 4-color code works .

The resistor, resists the flow of current this is useful for reducing the current to protect devices, or as a voltage divider.

Resistors are measured in ohms with the Omega symbol Ω. The value of the resistor can be as low as zero ohms (essentially a wire in a resistor package) up to 100 MΩ or even higher.

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