These light up paper circuit cards were much easier to make than I expected and only need a few inexpensive materials.

Discover how to build a simple wireless power transfer system at home using readily available components like enameled copper wire, an LED, a 2N2222A transistor, and a 9V battery. This step-by-step ...

A blast from the Elektor archives: this 1998 battery tester uses a simple LED display to reveal a battery’s true condition under load — even below 1 V.

This design idea (Figure 1) shows how easily “new flesh can be added to the old bones” and how some new functions can be added to the simple LED display that was published earlier. Figure 1 Upgraded ...

This expandable LED display for a microcontroller in Figure 1 has a simple interface with only 6 data/control wires and can be easily accommodated to a DIY design. The display has static indication.