This old 4-channel circuit was found in the December 1994 Electronics Now magazine. The circuit uses a 556 as a modulator. Note the code programming key.
This conventional astable uses two NPN transistor and was found in a publication of the year 1968. The...
This simple effect circuit for musical instruments and stereos was found in a 1987 publication. Powered by...
This circuit is a suggestion from a Radio Electronics from October 1964. We found it in the patent...