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.
This oscillator circuit for sinusoidal audio signals with operational 741 requires a symmetrical power...
Found in a 1974 Radio Shack documentation. This circuit must have a connection to the ground of...
This sensitive circuit detects the live pole of a power grid or outlet. The circuit makes use of a high...