How can they teach History when the text books are basically fantasy? Publishers print what they know will sell, not was is factual. We were taught Marconi discovered radio frequency, when Telsa was responsible and there was a Supreme Court ruling to the fact. Yet teachers taught it was Marconi. One example of how slanted things can become and are perpetuated.
Many people were involved in the
invention of radio in its current form. Experimental work on the connection between
electricity and
magnetism began around 1820 with the work of
Hans Christian Ørsted, and continued with the work of
André-Marie Ampère,
Joseph Henry, and
Michael Faraday. These investigations culminated in a theory of
electromagnetism developed by
James Clerk Maxwell, which predicted the existence of
electromagnetic waves.
Maxwell published
A Treatise on Electricity and Magnetism in 1873, stimulating many people to experiment with
wireless communication. Others experimented without the benefit of his theories. It is considered likely that the first intentional transmission of a signal by means of electromagnetic waves was performed by
David Edward Hughes around 1880, although this was considered to be induction at the time. The first systematic and unequivocal transmission of EM waves was performed by
Heinrich Rudolf Hertz and described in papers published in 1887 and 1890. Hertz famously considered these results as being of little practical value.
After Hertz's work many people were involved in further development of the
electronic components and methods to improve the transmission and detection of electromagnetic waves. Around the turn of the 20th century
Guglielmo Marconi, developed the first apparatus for long distance radio communication.
[1] On 23 December 1900,
Reginald A. Fessenden became the first person to send audio (
wireless telephony) by means of electromagnetic waves, successfully transmitting over a distance of about 1.6 kilometers, and six years later on
Christmas Eve1906 he became the first person to make a public radio broadcast.
[2][3]
Invention of radio - Wikipedia, the free encyclopedia
Tesla[edit]
In the early 1890s
Nikola Tesla began research into high frequency electricity. During his visit to the Paris
Exposition Universelle in 1889 Tesla learned of Hertz's experiments with electromagnetic waves using coils and spark gaps and proceeded to duplicate those experiments.
[60][61] Tesla came to the incorrect
[62] conclusion that Maxwell, Lodge, and Hertz were wrong in their findings that airborne electromagnetic waves (radio waves) were being transmitted and instead attributed it to what he called “electrostatic thrusts”,
[63] with the real signals being conducted by Earth currents.
[64]
In 1891 he developed various
alternator apparatus that produced 15,000 cycles per second and developed his own very large air-gapped coil, known now as a
Tesla coil.
[65][66] Tesla's primary interest in wireless phenomenon was as a power distribution system.
[67] By 1892 he was delivering lectures on high potential/high frequency alternate currents"
[68] and went on to demonstrate "wireless lighting"
[63] in 1893
[69] including lighting
Geissler tubes wirelessly. Tesla proposed this wireless technology could be developed into a system for the
telecommunication of
information.[
citation needed]