This circuit was obtained in an old Elektor and can be adapted to use white power LEDs. The transistor must be equipped with a heat sink. The circuit has a battery charger.
April 2017 - Mouser Electronics already has the MAX4007 from Maxim Integrated in its inventory, an...
This circuit was obtained from an English magazine from 1979, but can be easily assembled today...
Found in a 1978 publication, this circuit uses germanium transistors and drives a small 20 to 50...