[Eric Wasatonic] had a box of SWB2433 transistors that he had very little information about. In order to discover their properties, he fired up his curve tracer to compare these transistors with more ...

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 ...

Frank Hertel’s project: three individually dimmable LED lights. (Frank is the master of recycling; the wooden mounting pedestals are the panels from a decommissioned ATI console!) Thanks for your ...

The circuit has been constructed to provide an in-circuit system that will test the integrity of electronic components such as Silicon Controlled Rectifiers, diodes, and PNP or NPN transistors. 4093 – ...

With cycling safety in mind, I bought a pair of low power red LED things that replace the bungs in the end of drop handlebars. They are a neat way to get a bit of extra visibility – and to give a ...

Light-emitting diodes (LEDs) are often used with a voltage source from a power-supply output voltage. The output voltage increases until the current through the LEDs reaches the value of the ...

Transistors, the tiny switches that flip on and off inside computer chips, have long been the domain of electricity. But scientists are beginning to develop chip components that run on light. Last ...