This circuit was found in December 1983 Radio Electronics magazine. The maximum output current is 1 A and the supply voltage ranges from 4 to 28 V.
In the figure we have an improved method of varying the voltage of a 7812 regulator. The circuit is...
This 5-range current measurement circuit was found in the September 1989 issue of Radio...
Found in an old English publication this circuit uses a dual gate MOSFET. Coils not specified....