Found in a magazine 73 for radio amateurs of the 90s, this circuit converts a continuous voltage and another continuous voltage, but with insulation between the circuits.
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...