This circuit was found in a 1967 Raytheon manual. The transistors are from the time. Equivalent modern transistors can be tried out.
This circuit, well known, since it is already present in other points of this website, is from an...
This 12 V source provides 12A of maximum current and is suitable for powering mobile equipment. The...
This circuit is from a 1976 documentation. It uses an operation that is still common in our...