This circuit drives 4 sequences of 5 LEDs that can be of any color. The frequency depends on the characteristics of the photosensor. The circuit is from an 80's documentation.
This circuit was found in a 1977 documentation. With it we have the direct indication, through LEDs...
In the figure we have the CMOS logic test circuit developed with the 4049. The circuit activates three...
This headlight reminder for your car was found in the May 1970 issue of Radio Electronics...