Mini Organ (CB21653E)

This toy organ was found in Popular Electronics from January 1967. It can be constructed from modern equivalent transistors.

Vibrato (CB23942E)
This sound effect circuit was obtained from an article in the April 1969 issue of Radio...
Robot Eyes (CB12397E)
Found in a 1990 Electronics Handbook, this circuit causes an LED to flash when the phototransistor receives...
Sound Effects (CB26015E)
Found in the May 1997 issue of Electronics Now, this circuit produces a variety of sound effects for...