Zum Selbermachen einstellbare Geschwindigkeit NE555 + CD4017 laufendes LED-Licht Lötprojekt - UK Post
This kit is mainly composed of a clock generation circuit and a decimal counter circuit. It is a self-excited multi-vibrator with NE555 as the core. The clock oscillation signal of NE555 is continuously added to pin 14 of CD4017.