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 ...

An astable 555 multivibrator circuit, where the timing characteristics are determined by the interplay of an inductor, resistor, and diode.

The project is aimed at Arduino-based circuits, but any chip with an ADC will work. The 555 timer is used as a free running oscillator.

Three new Star Simpson’s Circuit Classics boards have arrived at the Adafruit online electronic store in the form of the Dual-LED Flasher, the Stepped Tone Generator, and the Bargraph Voltage ...