This benchtop power supply with various output voltages from 1.5 to 12 V was found in Radio Electronics magazine from August 1960. The circuit uses power transistors of the time.
This oscillator, from an old Argentine publication from 1973, uses the inductance of the 500 ohms...
Found in Popular Elecronics, this configuration also appears in this section, but obtained from other...
The operational ones used in this project are old types from National Semiconductor, since the...