We found this touch control on a Popular Electronics from 1970. The circuit makes use of an integrated of the time. It can be adapted to use modern equivalent components.
This circuit is from an Electronics World of 1964. The circuit can be made with modern...
The Variable Frequency Oscillator (VFO) or Variable Frequency Oscillator shown in the figure can...
This guitar effect circuit was found in a 2002 documentation. The circuit can be powered by a 9 V...