Here I would like to introduce a simple circuit for a LED flasher. Two
transistors of the BC 546A series, which are connected to a multi-vibrator, form the core. The circuit is also called astable flip-flop and can be used very versatile. In addition to the flasher
circuit shown here, it is also used for tone generators or electronic organs. A circuit diagram is shown in the following.
Alternatively, the NE555 timer IC can also be used to set up a simple flasher circuit. In addition to two light-emitting diodes, only a few common components are required to set up the flasher
circuit. The flashing frequency can be changed over a wide range by varying the resistance values and the capacitance of the electrolytic capacitor. According to the following scheme the circuit
was realized on a breadboard.