This simple charger was found in a 1980s documentation. The transistor may be the TIP42 with a heat sink. R1 adjusts the load current. The transformer has 1 A of secondary current.
This circuit was found in a 1986 publication. However, it can still be easily assembled, as the...
This circuit was published in Radio Electronics magazine in June 1959. The circuit uses an...
This circuit is based on an old Siemens integrated that can now be found very easily. It allows the...