Transmitted microwaves over distance of 75 feet in 1895.
Had transmitted microwaves nearly a mile by 1896.
|Did not pursue commercialization.
||Invented closed circut and coupled coils for transmitters.
||Did not recognize the significance when Hertz published his findings in 1888.
||Developed the triode amplifier and the Audion tube.
||Late upon beginning research into space telegraphy.
||First audio transmission by radio (1900). Also, the first two-way transatlantic radio transmission (1906), and the first radio broadcast of entertainment and music (1906)
||Not the first to transmit Morse code.
||Henry detected electromagnetic effects at a distance of two hundred feet.
||He was focused on wired telegraphy and researched self-inductance.
||By 1888, Hertz had studied and understood the work of Maxwell and, by design, produced the first clear and undisputed experimental evidence for the transmission and reception of radio waves.
||Hertz took this work no further, did not exploit it commercially, and famously did not consider it useful.
||In 1879, Hughes began research into radio waves. He noticed electrical interference in an induction balance he was working with. The observed effect was due to radio waves and he discovered and improved the coherer.
||Hughes was not trying to design equipment for wireless communication. His discovery was taken no further.
||On 14 August 1894 Lodge sent a radio message in Morse code.
||Did not pursue further.
||In 1872, received a patent for a "wireless telegraph". Patent utilizes atmospheric electricity to eliminate the overhead wire used by the existing telegraph systems.
||His patent U.S. Patent 129,971 was for the purpose of receiving and imparting atmospheric electricity.
||In summer 1895, Marconi sent signals 1.5 km.
In 1896, applied for British patent protection for a radio system. In 1900, he was granted British patent No. 12,039.
Transmission over 6 km in March and May 1897.
Transatlantic transmission on 12 December 1901.
Transmission over 3,378 km in February 1902.
Transatlantic message on 17 December 1902.
In 1897 Marconi founded "Wireless Telegraph and Signal Company" and exploited the "Marconi System" of radio commercially.
He shared the 1909 Nobel Prize in Physics with Karl Ferdinand Braun, "in recognition of their contributions to the development of wireless telegraphy".
|His 1901 transatlantic transmission is disputed.
Many of Marconi's system components were developed by others. Oliver Lodge claimed British patent of 1900 to contain his own ideas which he failed to patent.
||By 1864 Maxwell had become the first person to demonstrate theoretically the existence of radio (electromagnetic) waves, which are used by all radio equipment.
||Maxwell did not generate or receive radio waves.
||Confirmed laboratory demonstration of radio on 7 May 1895. In 1896 or 1897 publicly demonstrated the sending of a signal 250 m between two campus buildings. By 1900 he had reliable communications over 25 miles.
||Was not the first to send signals significant distances.
Tesla developed means to reliably produce radio frequency currents.
In 1891 and afterwards, lectured about high-frequency devices and demonstrated devices using power without the use of wires.
Referring to a demonstration of his wireless equipment in 1893 the IEE said "the apparatus that he employed contained all the elements of spark and continuous wave that were incorporated into radio transmitters before the advent of the vacuum tube".
By 1895, stated that he had the ability to transmit signals under 50 miles.
In 1897, Tesla applied for protection for the radio arts. In 1900 Tesla was granted U.S. Patent 645,576 and U.S. Patent 649,621.
In 1898, demonstrated a radio controlled boat in Madison Square Garden that allowed secure communication between transmitter and receiver.
After 1915, assisted the Telefunken engineers in constructing the Telefunken Wireless Station (the "Arco-Slaby system") in Sayville, Long Island.
No independently confirmed radio transmissions before 1898.
Primarily because of financial difficulties, Tesla never completed his "worldwide wireless system". The Wardenclyffe Tower transceiver that he began at Shoreham on Long Island, New York was eventually torn down.
||Ward was the first person to be granted a US patent relating to wireless telegraphy.
||His patent U.S. Patent 126,356 was for the purpose of receiving and imparting natural electricity.