This circuit appeared in the May 1983 issue of Radio Electronics magazine. It is based on the dedicated integrated circuit CEM3340. The circuit provides signals with various waveforms.
For those who like experimental circuits, here is a sequential flasher system with LEDs, which can be...
This circuit was found in an ancient American documentation. The integrated circuit is of the time...
This circuit was found in a 1977 Radio Shack documentation. The circuit is tuned to 1.4 kHz, but...