History of Radio

By kchaemker

  • Heinrich Hertz detects and produces radio waves.

    Heinrich Hertz detects and produces radio waves.
    Heinrich Hertz conducted an experiment, using a high voltage induction coil. He was able to transmit radio waves through his experiment.

  • Marconi establishes first radio link between England and France.

    Marconi establishes first radio link between England and France.
    He managed to do this through multiple experiments consisting of a patent through England, and through his own developed company "Wireless Telegraph & Signal Company Limited". This was later re- named "Marconi’s Wireless Telegraph Company Limited".

  • Valdemar Poulsen patents an arc transmission that generates continuous radio waves, producing a frequency of 100 kHz and receivable over 150 miles.

    Valdemar Poulsen patents an arc transmission that generates continuous radio waves, producing a frequency of 100 kHz and receivable over 150 miles.
    He was an electrical engineer, who managed to produce a frequency of 100 kHz, which was recievable for over 150 miles. He did so through an improved continuos arc transmitter.

  • Audion Tube

    Audion Tube
    The Audion Tube is an electronic amplifying vacuum tube invented by American electrical engineer Lee De Forest in 1906. The Audion Tube allowed for signals to be amplified over radio waves.

  • First radio program of voice and music broadcast in the U.S. (by R.A. Fessenden)

    First radio program of voice and music broadcast in the U.S. (by R.A. Fessenden)
    On Christmas Eve, he used a synchronous rotary-spark transmitter for the first radio program broadcast. This is the first known amplitude modulation or AM radio.

  • R.A. Fessenden invents a high-frequency electric generator that produces radio waves with a frequency of 100 kHz.

    R.A. Fessenden invents a high-frequency electric generator that produces radio waves with a frequency of 100 kHz.
    Canadian radio pioneer who developed a generator through an oscillation tank and an antenna circuitry. He did so off of the works based off of Marconi, Alexander Bell, and Thomas Edison.

  • Edwin Armstrong develops the superheterodyne radio receiver.

    Edwin Armstrong develops the superheterodyne radio receiver.
    The principle of his basic receiver design is now the basis for all radios in use now. This allowed for mixed signals to be ran through an oscillator to produce sun and difference frequency components.

  • FM Radio is born

    FM Radio is born
    FM was born because of Edward Armstrong, who got the first patent for frequency modulation, otherwise known as FM radio. It equates a modulation method with a range of frequencies.