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Magnifying transmitter - Nikola Tesla
Magnifying transmitter - Nikola Tesla

The Colorado Springs lab possessed the largest Tesla Coil ever built, known as the “Magnifying Transmitter”. This was not identical to the classic Tesla Coil. According to accounts, Tesla managed to transmit tens of thousands of watts of power without wires using the magnifier. Tesla posted a large fence around the coil with a sign, “Keep Out – Great Danger”.

Tesla’s Magnifying Transmitter, at fifty-two feet in diameter, generated millions of volts of electricity and produced lightning bolts one-hundred-thirty feet long (forty-one metres). It was a three-coil magnifying system requiring alternative forms of analysis than lumped-constant coupled resonant coils presently described to most.

The Magnifying Transmitter resonated at a natural quarter wavelength frequency.

Tesla also worked with the magnifying transmitter in a continuous-wave mode and in a damped-wave resonant mode. The Magnifying Transmitter produced thunder which was heard as far away as Cripple Creek. He became the first man to create electrical effects on the scale of lightning.

People near the lab would observe sparks emitting from the ground to their feet and through their shoes. Some people observed electrical sparks from the fire hydrants (Tesla for a time grounded out to the plumbing of the city).

The area around the laboratory would glow with a blue corona (similar to St. Elmo’s Fire). One of Tesla’s experiments with the Magnifying Transmitter destroyed Colorado Springs Electric Company’s generator by back feeding the city’s power generators, and blacked out the city. The city had a backup generator and company officials denied Tesla further access to their feed if he did not repair the city’s primary generator at his own expense.

The generator was working again in a few days.

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About Author


Edvard Csanyi

Electrical engineer, programmer and founder of EEP. Highly specialized for design of LV/MV switchgears and LV high power busbar trunking (<6300A) in power substations, commercial buildings and industry fascilities. Professional in AutoCAD programming. Present on


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  2. Jonah Lissner
    Jun 25, 2014

    Proposal for Unitary Iono-Magnetospheric Power Generation Theory
    Jonah Lissner
    Copyright 2014 by Jonah Lissner. All rights reserved by the Author.


    We of this planet have the basics for regular energy generation: Sun, Trees, Water and Earth. Yet how can we utilize the physical world to regenerate power at low economic and material cost? How much energy is needed for our power-usage projects and how will we engineer the power systems of this century? How is power most efficiently relayed in an open system? One can answer by generation, transmission, or transduction, and the associated principles of harmonic oscillation of radio frequency wavefunctions of electronic and magnetic band-energy in an open system.

    Ionospheric and geophysical seismic, tectonic asymmetries associated with solar and geophysical energetic storms of the interaction between Van Allen radiation belts and Tesla-Schumann Resonances, radiative and induced negative electronic plasma-physics and -weather anomalies, peaks or nadirs are the relevant problem to be addressed regarding problems of power-generation -relay and power-loads in new engineering technology.

    Feb 15, 2014

    Iam impressed…. give me more details

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