[Ernie]

Well Tinks a diode is a component on a circuit board that allows electricity to flow through it one way but not the other, like a one way valve in a water pipe. They are usually used in hi-fi equipment and radio and television and they come in various sizes dependant on what they are being used for, the larger ones are normally used in rectifiers and the smaller ones are used in low current devices. (A rectifier converts A/C alternating current to D/C direct current).