This circuit is from an old Signetics documentation. It can be implemented with modern operational amplifiers. The power supply must be symmetrical.
This circuit with the LM339 voltage comparator was found in an American documentation from 1991....
With an output of 7.5 W at 110 V this circuit was found in a 1968 Motorola documentation. The circuit has...
This circuit is from old American documentation, but the components used can still be found quite...