This circuit makes use of a mechanical delay line to produce the reverberation effect. This is a '80s setup, showing both channels for a stereo system.
This circuit is from an American documentation from 1975. The single junction transistors can be...
This circuit is of an old Argentine magazine of the 70's. The difficulty for its assembly is in...
This small control for DC motors up to approximately 1 A uses an operational amplifier that admits...