The red light-emitting diode was made cheap enough (barely) for commercial use in 1968, but you didn't see many of them in cars until well into the 1980s. The leaders at Honda, though, must have ...

If you’re working with 3.3V or 5V circuits, it’s easy for you to throw on a power or status LED here or there. [Tom Gralewicz] has found himself in a pickle, though, often working on projects with ...

This Design Idea gives two versions of an indicator light that changes from green to red as a battery discharges. There are many circuits that do this sort of thing, but all the ones I have seen are ...