This circuit was obtained in an old Popular Electronics. It makes use of quite common components. The speed of the effect is set to R7. The circuit drives 20 LEDs.
This automotive circuit was found in the September 1992 issue of Radio Electronics magazine. The...
This 80's circuit uses an integrated amplifier of the era, but nothing prevents it from being...
This VCO with a common operational amplifier was found in an old American documentation. The...