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 is from an article in Radio Electronics magazine from August 1972. The circuit is...
Found in 1969 RCA documentation, this circuit maintains constant current in the filament of a lamp...
The integrated circuit used in this application is uncommon today. The circuit is from American...