This circuit supplies a voltage of 42 V, plus a symmetrical voltage of 12 V with 1 A. The voltage regulators must be mounted on heat sinks. The transformer is 35 + 35 V with 3 A.
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...