This circuit is from the 80's integrated circuit manual itself. The component is not as common today as the MOS transistor used. The circuit can be adapted for modern applications.
The CK722 transistor used in this circuit is one of the first commercial types in the world. The...
This automatic dimmer for incandescent lamps was found in a European publication from the 1980s. The...
This traditional doubler configuration with the 555 can be found in other articles on the author’s site....