This high-sensitivity circuit was found in a 1980s documentation. The source can be a 9 V battery with a splitter to make it symmetrical. The shock can be 200 uH or more.
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....