Here is a 1Hz pulse/frequency generator using the popular timer IC 555 which is wired as an Astable Multivibrator. The output pulses can be indicated visually by the LED. An Astable Multivibrator, ...

Used in a variety of timer, pulse generation, and oscillator applications, the 555 was designed in 1971 by Hans Camenzind. A favorite for many engineers, the 555 is still in widespread use due to its ...