history of radio

pocket transistor radio,

1954 BCE

In 1954, the Regency company introduced a pocket transistor radio, the TR-1, powered by a "standard 22.5 V Battery."

first US licensed commercial broadcasting station

1920 BCE

It is commonly attributed to KDKA in Pittsburgh, Pennsylvania, which in October 1920 received its license and went on the air as the first US licensed commercial broadcasting station on November 2, 1920 with the presidential election results as its inaugural show, but was not broadcasting daily until 1921.

charles David Herrold

1909 BCE

In April 1909 Charles David Herrold, an electronics instructor in San Jose, California constructed a broadcasting station. It used spark gap technology, but modulated the carrier frequency with the human voice, and later music.

Roberto Landell de Moura

1900 BCE

In 1900, Brazilian priest Roberto Landell de Moura transmitted the human voice wirelessly for a distance of approximately a half mile.

Guglielmo Marconi

1894 BCE

1894 the Italian inventor Guglielmo Marconi built the first complete, commercially successful wireless telegraphy system based on airborne Hertzian waves (radio transmission). Marconi demonstrated application of radio in military and marine communications and started a company for the development and propagation of radio communication services and equipment.

Heinrich Rudolf Hertz

1888 BCE

In 1888 Heinrich Rudolf Hertz was able to conclusively prove transmitted airborne electromagnetic waves in an experiment confirming Maxwell's theory of electromagnetism.After the discovery of these "Hertzian waves" it would take almost 20 years for the term "radio" to be universally adopted for this type of electromagnetic radiation many scientists and inventors experimented with wireless transmission and trying to develop a system of communication.