This charger was found in the February 1978 issue of Radio Electronics magazine. The circuit is for low current, only 150 mA, and has a 12 V transformer in the power source.
This circuit, from the 90's, is intended for operation with vinyl record players of the time, as...
Using a zener diode it is possible to change the linearity of the scale of an analog instrument by...
Found in American documentation from the 1980s, this circuit prolongs the ringing of a doorbell or chime...