This 5V power supply with a 1.5 to 3 A current was found in Maxim documentation from the 90s. The integrated circuit is the MAX741D.
I found this circuit in a 1986 English magazine. It can still be easily assembled, exchanging Q1...
We found this circuit in an Argentine publication from the 70s. The coil can be made with 80 turns...
Found in General Electric documentation from 1967, this circuit makes use of an unusual...