This constant current charger from 1997 Linear Technology Applications uses common components at the time. The transformer is the critical component, being designed according to the load voltage.
This circuit is from a Radio Electronics magazine from August 1990. The circuit uses components from the...
The circuit we show is part of an article that taught its complete assembly. The article is from...
This ultra-simple polarity indicator uses common green and red LEDs and can work with 3 to 9 V...