US patent 1119732 Nikola Tesla 1907 Apparatus for transmitting electrical energy

Drawing from US patent no. 1119732, "Apparatus for transmitting electrical energy", filed May 4, 1907 by inventor Nikola Tesla. It consists of a design for a wireless power transmitter. The circuit is an advanced version of his Tesla coil which he called a "magnifying transmitter" which Tesla had been developing since around 1896 and in 1900 installed in his Colorado Springs laboratory. At the base of the tower, a capacitor (G) is connected to the primary winding (C) of an air core transformer. When an oscillating current from a generator (not shown) is applied to the primary, it creates resonant oscillating currents that induce a very high oscillating voltage in the secondary winding (A). One end of the secondary is grounded (E) while the other end is connected to a tall, thin "resonator" coil (B) The top end of the resonator coil is connected through a vertical metal pipe (B') to a large torus-shaped sheet metal capacitive terminal (P) at the top of the tower. The resonator coil is tuned to resonance with the transformer and steps up the voltage still further, to millions of volts on the top terminal. The rounded shape of the top terminal is designed to prevent air breakdown and arc discharges. Tesla believed this device could transmit power long distances without wires into homes and factories by exciting standing waves of current in the Earth. In 1901 Tesla began construction of a wireless transmitter based on this design, now called the Wardenclyffe tower, at Shoreham, Long Island, New York. The station was never finished and was torn down in 1916. There is no evidence he achieved long distance power transmission.