This is a small size led flasher built with the 555 timer IC that is powered from 2 x 1.5V batteries. The circuit can be used as a flashing metronome, dark room timer, memo-reminder or other similar ...

You know how it is. You’ve got that new project running, and while it doesn’t consume much power, it also doesn’t give much indication of whether it’s functioning or just sitting there with a dead ...