This circuit fires with the noise captured by the touch of a sensor. Signal shapes are given next to the diagram. The circuit is from the 80s, using components from that time.
This circuit was obtained from an American 80's documentation. The balanced mixer can be shown in...
Found in a 90s Electronic Design, this circuit generates harmonics from a sinusoidal input signal....
Published in an old Popular Electronics, this circuit makes use of components that are still...