This circuit was found in a Popular Electronics from the 90s. The effect circuit uses components that are still common today. In fact, the circuit has only 3 channels of 12 LEDs.
This circuit uses half of the LM158 operational double but can be used in the series as the LM258,...
This circuit generates audio tones in a speaker with controlled frequency and volume. The...
This circuit was obtained from an article in Radio Electronics magazine in October 1966. It...