In this lesson, students build two circuits and explore how transistors function. When Bell Labs introduced the transistor in June of 1948, a spokesman proudly announced "This cylindrical object . . .

A previous Design Idea describes a circuit that uses an astable multivibrator to drive an LED (Reference 1). The circuit in Figure 1 uses a simpler alternative approach. The circuit uses a 2N3904 NPN ...

If you open up the perennial favourite electronics textbook The Art Of Electronics and turn to the section on transistors, you will see a little cartoon. A transistor is shown as a room in which ...

[Kevin Darrah] wanted to make a simple 3.3V regulator without using an integrated circuit. He wound up using two common NPN transistors and 4 1K resistors. The circuit isn’t going to beat out a cheap ...

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 ...