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 ...

Using a CMOS 555 timer and a single NPN transistor, you can drive as many as seven LEDs using a minimal amount of voltage and power from a single NiMH (nickel-metal-hydride) AA cell. The circuit works ...

Take this Christmas tree for example, which uses a 555 timer and a CB4017 decade counter in order to drive some blinking LEDs. The ICs are through-hole, making the circuit fairly accessible to new ...

If you’re not familiar with the 555 timer ... Although using an RC relaxation oscillator at tens of MHz is not a very practical thing to do, using this circuit for very short one-shot pulses ...