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 obtained in a General Electric documentation from the 80's, and can be used as a...
This circuit appears in various parts of this site and this section, with diverse origins. This is from...
November 2016 - The TL3780 ultra-miniature E-switch touch switches can now be obtained from Mouser...