Found in documentation from the 1980s, this circuit can have several adaptations to use modern transistors and LEDs instead of the lamp. The power supply voltage can also be changed.
This circuit is from an Italian publication from 1988 but can still be easily assembled....
We found this circuit in a Japanese publication in 1967. The circuit consists of a 15 W audio...
This charger circuit provides an initial voltage of 2.5 V and when the current reaches 180 mA the...