This circuit was found in an American documentation from 1975. The components of the time can no longer be found easily, but they can be tested equivalent.
This is the traditional configuration of a 6 or 12 V source with 7806 or 7812 integrated circuits, for a...
This fader or guitar fading circuit was found in an American documentation from the 1980s. The...
Found in documentation from the 1960s, this power supply employs germanium diodes from the time....