Nikola Tesla AC Motor (1883): Tesla carried detailed plans for this AC motor in his head (a particular talent of his) until he could build a physical model the next year. The alternating current created magnetic poles that reversed themselves without mechanical aid, as DC motors required, and caused an armature (the revolving part of any electromechanical device) to whirl around the motor. This was his rotating magnetic field put into practice as a motor; within two years, he would use it in AC generators and transformers as well.
"Marconi is a good fellow. Let him continue. He is using seventeen of my patents. "
TESLA'S AC MOTOR - Works with The Principle
of Rotating Magnetic Field
EGG OF COLUMBUS TO DEMONSTRATE THE POWER OF THE
ROTATING MAGNETIC FIELD
TESLA COIL 1890
Tom and Donna Blog Spot
From Harry Lavern Twining 1909 - Streamer Going Through Boy's Body Experiment
The electrical coil named for its inventor is one of Tesla's showiest inventions, and he used it to its full dramatic extent in demonstrations held in his New York City lab. The coil uses polyphase alternating currents -- another of Tesla's discoveries -- to create a transformer capable of producing very high voltages. It brought forth impressive crackling sparks and sheets of electric flame that impressed the electrically savvy and the layman alike. They're primarily used for entertainment today.
Radio (1897): Tesla first sent a wireless transmission from his lab at Houston Street in New York City to a boat on the Hudson River -- 25 miles (40 km) away -- in 1897; he would've done this sooner but for a fire that destroyed his previous lab in 1895. Tesla invented everything we associate with radio -- antennas, tuners and the like -- but an inventor named Guglielmo Marconi was given the actual credit. In 1943, the U.S. Supreme Court ruled that Tesla's patent had precedence, but the public already considered Marconi the father of radio.
Apparatus in action illustrating the first step in the evolution of the magnifying transmitter in the laboratory at 35 South Fifth Avenue. (Article by T.C. Martin ["Tesla's Oscillator and Other Inventions"], Century Magazine, April 1895.
"This coil, which I have subsequently shown in my patents Nos. 645,576 and 649,621, in the form of a spiral, was, as you see, [earlier] in the form of a cone. The idea was to put the coil, with reference to the primary, in an inductive connection which was not close—we call it now a loose coupling—but free to permit a great resonant rise. That was the first single step, as I say, toward the evolution of an invention which I have called my "magnifying transmitter." That means, a circuit connected to ground and to the antenna, of a tremendous electromagnetic momentum and small damping factor, with all the conditions so determined that an immense accumulation of electrical energy can take place." NT
Tesla built on these discoveries and inventions to create the first wireless remote control boat, fluorescent and neon lights (which he did indeed bend into letters), wireless bulbs that were lit by energy from the earth and an AC power plant that harnessed the hydroelectric power of Niagara Falls. He even had a hand in the creation of robotics. His system of delivering power to homes and businesses using AC eclipsed the DC power advocated by his former employer Thomas Edison. (We still receive AC power in our homes today.) By the time Tesla died in 1943, his money and fame were on the wane, but his inventions and discoveries have made much of our current technology possible.
Tesla Remote Control Boat
Tesla's tublike craft powered itself there were several large batteries on board. Radio signals controlled switches, which energized the boat's propeller, rudder, and scaled-down running lights—simple enough in concept, but quite difficult to accomplish with existing devices. Even registering the arrival of a radio signal pulse taxed the rudimentary technology. Tesla invented a new kind of coherer (a radio-activated switch) for this purpose, essentially a canister with a little metal oxide powder in it. The powder orients itself in the presence of an electromagnetic field, like radio waves, and becomes conductive. If the canister is flipped over, after the pulse's passage, the powder is restored to a random, nonconductive state.
Tesla contrived for a number of things to happen when the coherer conducted, most importantly for a disk bearing several differently organized sets of contacts to advance itself one step. Thus, if the contacts had previously connected the combination "right rudder/propeller forward full/light off," the next step might combine "rudder center/propeller stop/lights on." And with the aid of a few levers, gears, springs, and motors all would be accomplished, including a final step, flipping the coherer over so that it was ready to receive the next instruction.
Applications The world of 1898 had little understanding or use for Tesla's brilliant idea. Though he rather darkly imagined a military clamor for such things as radio-guided torpedoes, government interest did not materialize. (In one of history's curious footnotes, Tesla's good friend Mark Twain wrote immediately to say he was anxious to represent Tesla in the sale of this "destructive terror which you have been inventing" to England and Germany.) The navy did finance some trials in 1916, but the money went to one of Tesla's competitors. He remarked bitterly he could find no listeners until his patent had expired.
Tesla's fears (and Twain's business hopes) were misplaced. The world's military establishments discovered many destructive terrors, but radio-controlled devices didn't number among them in any significant way until late in the twentieth century, with refinements in rocketry and guided bombs. Radio control remained a novelty, an exciting field for experimentalists and specialists, until the launching of the Space Age and the orbiting of myriad commercial and military satellites, all under remote control.
Inside the Lab Index
Example of Tesla's Fluorescent Light Invention Powered by Electricity Without Wire from The Tesla Coil Resonant Transformer.
AC power circuit is a sine wave. Audio and radio signals carried on electrical wires (such as an antenna) are also examples of alternating current. Presscore.ca
A Tesla coil is an electrical resonant transformer circuit invented by Nikola Tesla around 1891. It is used to produce high-voltage, low-current, high frequency alternating-current electricity. Tesla experimented with a number of different configurations consisting of two, or sometimes three, coupled resonant electric circuits.
Tesla used these coils to conduct innovative experiments in electrical lighting, phosphorescence, X-ray generation, high frequency alternating current phenomena, electrotherapy, and the transmission of electrical energy without wires. Tesla coil circuits were used commercially in sparkgap radio transmitters for wireless telegraphy until the 1920s, and in medical equipment such as electrotherapy and violet ray devices. Today their main use is for entertainment and educational displays, although small coils are still used today as leak detectors for high vacuum systems.
Questacon Lightning Simulator
A fluorescent lamp or a fluorescent tube is a low pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapor which produces short-wave ultraviolet light that then causes a phosphor coating on the inside of the bulb to glow. A fluorescent lamp converts electrical energy into useful light much more efficiently than incandescent lamps. The luminous efficacy of a fluorescent light bulb can exceed 100 lumens per watt, several times the efficacy of an incandescent bulb with comparable light output.
Fluorescent lamp fixtures are more costly than incandescent lamps because they require a ballast to regulate the current through the lamp, but the lower energy cost typically offsets the higher initial cost. Compact fluorescent lamps are now available in the same popular sizes as incandescents and are used as an energy-saving alternative in homes.
Nikola Tesla is the father of fluorescent lighting. In the 1890s he experiment with filament-less, gas-filled tubes and bulbs that glowed in the presence of high voltage. He saw these as a progression from the small, hot light bulbs invented by his rival Thomas Edison. Fluorescent lighting still works on principles established by Tesla: house current is stepped up by a small transformer to much higher voltages, which excites the mercury vapor sealed into the tube. The vapor fluoresces, or glows, using much less wattage than the incandescent system.
Tesla experimented with what he called "phosphorescent" lamps, it was French physicist Alexandre-Edmond Becquerel (1820-1891) who first conceived the idea of placing a fluorescent coating on the inner surface of a high voltage gas discharge tube. Tesla's investigations in the area of high-voltage RF power processing techniques did result in the very first high efficiency, high frequency lighting ballasts. His seminal lectures on the topic of high frequency lighting are, "Experiments With Alternate Currents of Very High Frequency and Their Application to Methods of Artificial Illumination," "Experiments with Alternating Currents of High Potential and High Frequency" and "On Light and Other High Frequency Phenomena" all to be found in the book Inventions, Researches and Writings of Nikola Tesla. It's interesting to note that the world's first commercial fluorescent lamps, introduced by the Westinghouse Electric Company at the 1939 New York World's Fair, were of the low-voltage 50-60 Hz hot cathode type still in common use today. Only since the late 1980s have more efficient high-frequency ballasts—some with great similarities to those developed by Tesla over 100 years ago—begun to gain wider acceptance.
A radio communication system requires two tuned circuits each at the transmitter and receiver, all four tuned to the same frequency."
So, the next time you pick up a wireless telephone, listen to your car radio or turn on a television set, give a quick thought to Nikola Tesla — the true father of radio.
Radio is that form of wireless communications in which the transmitter output takes the form of dissipating electromagnetic radiation, the radio waves spreading outward in all directions from an elevated antenna. Because the signal strength drops off quite rapidly as the distance from the source of radiation increases, faraway radio receivers have to be very sensitive to detect signals that may measure only a fraction of a microvolt per meter in strength. These radio waves had remained practically unknown until the 19th century when a number of important steps were taken by early investigators who developed techniques for their detection and measurement. This led to the 1886-1888 experiments of Heinrich Hertz which firmly established their existence.
Nikola Tesla's contribution to this story involved reworking the primitive sources of radio frequency current and crude tuned receiving circuits developed by his predecessors. A most important step was introduction of the coupled tuned circuit into his preliminary transmitter design. Some might recognize this as the configuration of the now familiar Tesla coil, with its primary and secondary circuits both tuned to vibrate together in harmony. By 1896 further refinements had resulted in a transmitter that could have signaled across the Atlantic, had such an attempt been made. Additional work resulted in the development of wireless receivers that also included two synchronized circuits. Between 1898 and 1903 Tesla was granted 10 U.S. patents covering his inventions in these two areas.