This circuit was suggested by National Semiconductor in one of its manuals. The LM108 integrated circuit, uncommon nowadays, can be replaced by an equivalent. The power supply must be symmetrical.
This configuration, found in many other circuits in this section, was obtained in a 1970s American...
This circuit for incandescent lamps was found in an American documentation from the 80s. The...
Found in old English documentation this circuit can be made with a BF245 or equivalent. Coils are...