Suggested by Motorola in 1968 documentation, this circuit has an efficiency of 70%. Power transistors are types of the time as are transformers.
This regulator is equivalent to 2 AA batteries providing a 5 V output voltage. The circuit is from...
Found in a 1970 publication by General Electric, this circuit makes use of a mobile...
Found in Popular Electronics, this sophisticated short-wave receiver requires a lot of skill from...