Magnifying transmitter

The magnifying transmitter is an advanced version of Tesla coil transmitter. It is a high power harmonic oscillator that Nikola Tesla intended for the wireless transmission of electrical energy. In his autobiography, Tesla stated that ". . . I feel certain that of all my inventions, the Magnifying Transmitter will prove most important and valuable to future generations." The magnifying transmitter is an air-core, multiple-resonant transformer that can generate very high voltages.

The first "Magnifier" was assembled in New York City between 1895 - 1898. In 1899 a larger magnifier was constructed in Colorado Springs, Colorado. This machine was used to conduct fundamental experiments in wireless telecommunications and electrical power transmission. Measuring fifty-one feet (15.5 m) in diameter, it developed a working potential estimated at 3.5 million to 4 million volts and was capable of producing electrical discharges exceeding one hundred feet (30 m) in length.

In 1899, Tesla moved his research to Colorado Springs. He chose this location because the polyphase alternating current power distribution system had been introduced there and he had associates who were willing to give him all the power he needed without charging for it. He kept a handwritten diary of his experiments in the Colorado Springs lab where he spent nearly nine months. It consists of 500 pages of notes and nearly 200 drawings, recorded chronologically between June 1, 1899 and January 7, 1900, as the work occurred, containing explanations of his experiments.

While in Colorado, Tesla constructed many smaller resonance transformers and conducted further research on concatenated tuned electrical circuits. Tesla also designed various sensitive devices for detecting received electrical energy, including rotating coherers. These used a clockwork mechanism of gears driven by a coiled spring-drive which rotated a small glass cylinder containing metal filings. These experiments were the final stage after years of work on synchronized tuned electrical circuits. These instruments were constructed to demonstrate how a wireless receiver could be "tuned" to respond to a specific complex signal while rejecting others. Tesla logged in his diary on January 2, 1900 that a separate resonance transformer tuned to the same high frequency as a larger high-voltage resonance transformer (which acted as a transmitter) received energy from the larger coil, one of many demonstrations of the wireless transmission of electrical energy.

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