This voltage inverter circuit was found in a Mullard transistor manual from 1960. Information on the transformers was given. Transistors are germanium types.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...