This PNP transistor power stage was found in the May 1969 issue of Radio Electronics magazine. The circuit uses a transformer for excitation and requires 10W input for full output power.
This switched or switched regulator was suggested by Texas Instruments in one of its application manuals....
This is one of the possible configurations using the LM139, 239 or 339 voltage comparators. The...
In the old original version of this circuit from 1989, the LED is common (we recommend 330-ohm...