Simply place the tool or object you want to magnetize inside the coil and briefly press S1. The generated single polarity field should magnetize the object if the material it is made to allow.
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....