KDKA would then become the first radio station officially licensed by the government. It was also Westinghouse which first began advertising the sale of radios to the public. While manufactured radios were finding their way into the mainstream, home-built radio receivers were a solution for some households. This began to create a problem for the manufacturers who were selling pre-made units. Under RCA, certain companies could make receivers, while other companies were approved to make transmitters.
The broadcasts quickly spread across the UK but failed to usurp newspapers until when the newspapers went on strike. At this point the radio and the BBC became the leading source of information for the public. In both the U. With the help of journalists, radio relayed news of the war to the public.
It was also a rallying source and was used by the government to gain public support for the war. In the U. The way in which radio was used also changed the world after World War II. While radio had previously been a source of entertainment in the form of serial programs, after the war it began to focus more on playing the music of the time. The "Top" in music became popular during this period and the target audience went from families to pre-teens up to adults in their mid-thirties.
Music and radio continued to rise in popularity until they became synonymous with one another. Sign up now to learn about This Day in History straight from your inbox. A total of 4 million copies sold in the first six days of its release. The album, released on the Premier label, included recordings of some of Fourteen-year-old Michael Carneal is indicted as an adult on three counts of murder and five counts of attempted murder for the shooting of his classmates at Heath High School in West Paducah, Kentucky.
On December 1, Carneal pulled out a pistol and fired 11 shots into a group of On December 12, , Pennsylvania becomes the second state to ratify the Constitution, by a vote of 46 to Pennsylvania was the first large state to ratify, as well as the first state to endure a serious Anti-Federalist challenge to ratification.
Pennsylvania was the most Live TV. This Day In History. History Vault. This Day in History. Captions English Add a one-line explanation of what this file represents. Summary [ edit ] Description Marconi's first radio transmitter.
It was a spark-gap transmitter which generated radio waves by an electric spark between two electrodes of a Righi spark gap left, on table. The high voltage to produce the spark was generated by an induction coil center powered by a battery on floor. A telegraph key right, on table in the primary circuit allowed the operator to switch the transmitter on and off rapidly, producing pulses of radio waves which spelled out text messages in Morse code.
The unique feature of this transmitter is that it includes Marconi's invention of a monopole antenna. Marconi found that by connecting one side of the transmitter to an elevated copper sheet "capacity area" top and the other side to ground earth , he could transmit longer distances than when using the previous dipole antennas invented by Hertz.
This crucial innovation reduced the frequency of the radio waves, and radiated vertically polarized waves which had a greater range. This work is in the public domain because it was published in the United States between and , and although there may or may not have been a copyright notice, the copyright was not renewed.
For further explanation, see Commons:Hirtle chart and the copyright renewal logs. Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works depending on the date of the author's death , such as Canada 50 years p. Capacitive copper sheet monopole antenna. You cannot overwrite this file.
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