Nikola Tesla German Patent 93255 - Circuit Controller for Converting Currents with a Low Number of Turns into Currents with a High Number of Turns by Means of Capacitor Discharges
Nikola Tesla German Patent 139465 - Method and Device for the Utilization of Electrical Impulses or Vibrations Sent from a Distance by the Ether or the Earth or Both
Nikola Tesla U.S. Patent 462,418 - Method of and Apparatus for Electrical Conversion and Distribution
Nikola Tesla German Patent 87269 - Device for Generating Electrical Currents with a Constant Number of Vibrations