Learn DC voltage regulator circuit, Types of, Fixed and Adjustable. How it works, for example, circuits using Zener diodes, transistors, and more.
Learn Unregulated power supply! Here an important basic. You should know. Diodes rectifier, Designing, reduce ripple, capacitors filter.
This is a 15V DC Regulator circuit at 400mA using IC-748 and 2N3055. Although it is an ancient circuit, but if you have the equipment ready. we may try to build it.
When I need to use DC regulator power supply 18V 1A for the transistors pre tone control circuits.