This 5 V power supply for TTL, Shields and microcontrollers is old, and the components can be replaced by modern equivalents. Transistor Q1 can be a TIP31 and Q2 can be a BD135.
This version of an astable CMOS with the 4069, and which appears elsewhere on this site and in...
Found in na 1970 EDN this circuit has a parallel regulation providing a symmetrical output of 15 V....
This circuit is the receiver for the previous remote-control transmitter. We found it in the same...