These are analogous to the terminals on a bipolar transistor, in that the source fulfills a similar role to the emitter, the gate to the base, and the drain to the collector. Thus the three basic ...

The transistor acts like an insulator or a switch that is turned off. When a positive voltage is applied to the base, electrons are pulled out of the junctions and they no longer act as barriers.

Electricity can race through. The transistor base (the "meat" of the sandwich) acts like the handle on a faucet. Turn it one way and current will gush through like water through a hose.

Speaking of the Pinecil, it uses an unorthodox driving circuit – it has an NPN transistor, but its base driven through a capacitor, so that only the AC component of the driving signal gets through.

Also called a "bipolar junction transistor" (BJT), it is one of two major transistor categories; the other is "field-effect transistor" (FET). Although the first transistor was bipolar and the ...