Operating at just 1.35 V this circuit was found in a 1969 Electronic Design. The circuit makes use of transistors of the time but can be implemented with current equivalents.
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...