THE CARBON COMPOSITION RESISTOR

By grinding carbon into a fine powder and mixing it with resin, a material can be made with different resistive values. Conductive leads are placed on each end of a cylinder of this material and the unit is then heated or cured in an oven. The body of the resistor is then painted with an insulating paint to prevent it from shorting if touched by another component. The finished resistors are then measured and sorted by value. If these resistors are overloaded by a circuit, their resistance will permanently decrease. It is important that the power rating of the carbon composition resistor is not exceeded.