We found this circuit in a 1969 General Electric documentation. The circuit uses transistors of the time and the diodes in the dotted board must be mounted on the output transistor heatsinks.
This amplifier was found in a Japanese publication in 1972. Transistors are uncommon today, and...
The current of this source is 200 mA at the most, and the output depends on the zener that may...
Found in Mallory documentation from 1968 this circuit uses an integrated circuit from that time. The...