This 1.5W tube amplifier was found in an American documentation from 1947. It is a direct rectification circuit without the need for a power transformer.
This circuit was found in an old Electronic Design. It makes use of sidacs and operational not very...
Although it was found in a British magazine 1976, this circuit can be easily upgraded with the...
This circuit that uses only transistors that are still common was found in a 1995 documentation. The TIP41...