This circuit was obtained from an American documentation from the 80s. Integrated circuits are from that time and are not easy to find today.
The output voltages of this power source are selected by a switch according to the capacitors. The...
This circuit is from a 90s Popular Electronics. The circuit employs a ZN461E that is not a common...
This circuit was found in Siliconix documentation from the 1980s. Equivalent operational...