A teacher I know is stuck, with only npn transistors in the supply cupboard and the need to create a reversible motor drive for an Arduino project. Reversing ‘bridges’ have four switches (relay ...

Using a transistor ... control circuits. We’ve embedded his twenty-minute video after the break. In it he talks about the use of transistors, the difference between NPN and PNP transistors ...

William Shockley improved on this design with his junction transistor, a three-layer sandwich of different types of semiconductor. The diagram illustrates the basic design of an NPN junction ...