History of radio
Encyclopedia
The early history of radio is the history of technology that produced radio instruments
that use radio wave
s. Within the timeline of radio
, many people contributed theory and inventions in what became radio
. Radio development began as "wireless telegraphy
". Later radio history increasingly involves matters of programming and content.
showed mathematically that electromagnetic waves could propagate through free space. Heinrich Rudolf Hertz
and many others demonstrated radio wave propagation on a laboratory scale.
Transmission and radiation of radio frequency energy was a feature exhibited in the experiments by Nikola Tesla
, that he proposed in 1892 and 1893 might be used for the telecommunication
of information
. The Tesla method
was described in New York in 1897. In 1897, Tesla applied for two key United States radio patents, , first radio system patent, and . Tesla also used sensitive electromagnetic receivers, that were unlike the less responsive coherer
s later used by Marconi and other early experimenters. Shortly thereafter, he began to develop wireless remote control devices.
In 1895, Marconi built a wireless system capable of transmitting signals at long distances (1.5 mi./ 2.4 km). From Marconi's experiments, the phenomenon that transmission range is proportional to the square of antenna height is known as "Marconi's law
". This formula represents a physical law
that radio devices use.
is a historical term used today to apply to early radio telegraph communications techniques and practices, particularly those used during the first three decades of radio (1887 to 1920) before the term radio came into use. Guglielmo Marconi
demonstrated application of radio in commercial, military and marine communications and started a company for the development and propagation of radio communication services and equipment. The field of radio development attracted many researchers, and bitter arguments over the true "inventor of radio" persist to this day.
, the Slaby-Arco wireless system was developed by Adolf Slaby
and Georg von Arco
. In 1900, Reginald Fessenden
made a weak transmission of voice over the airwaves. In 1901, Marconi conducted the first successful transatlantic experimental radio communications. In 1904, The U.S. Patent Office
reversed its decision, awarding Marconi a patent for the invention of radio, possibly influenced by Marconi's financial backers in the States, who included Thomas Edison
and Andrew Carnegie
. This also allowed the U.S. government (among others) to avoid having to pay the royalties that were being claimed by Tesla for use of his patents. For more information see Marconi's radio work. In 1907, Marconi established the first commercial transatlantic radio communications service, between Clifden
, Ireland and Glace Bay, Newfoundland
.
Julio Cervera Baviera
developed radio in Spain around 1902.
Cervera Baviera obtained patents in England, Germany, Belgium, and Spain. In May–June 1899, Cervera had, with the blessing of the Spanish Army
, visited Marconi's radiotelegraphic installations on the English Channel
, and worked to develop his own system. He began collaborating with Marconi on resolving the problem of a wireless communication system, obtaining some patents by the end of 1899. Cervera, who had worked with Marconi and his assistant George Kemp
in 1899, resolved the difficulties of wireless telegraph and obtained his first patents prior to the end of that year. On March 22, 1902, Cervera founded the Spanish Wireless Telegraph and Telephone Corporation and brought to his corporation the patents he had obtained in Spain, Belgium, Germany and England. He established the second and third regular radiotelegraph service in the history of the world in 1901 and 1902 by maintaining regular transmissions between Tarifa
and Ceuta
for three consecutive months, and between Javea (Cabo de la Nao) and Ibiza
(Cabo Pelado). This is after Marconi established the radiotelegraphic service between the Isle of Wight
and Bournemouth
in 1898. In 1906, Domenico Mazzotto wrote: "In Spain the Minister of War has applied the system perfected by the commander of military engineering, Julio Cervera Baviera (English patent No. 20084 (1899))." Cervera thus achieved some success in this field, but his radiotelegraphic activities ceased suddenly, the reasons for which are unclear to this day.
s, the company called British Marconi
was established in 1897 and began communication between coast radio station
s and ships at sea. This company along with its subsidiary American Marconi, had a stranglehold on ship to shore communication. It operated much the way American Telephone and Telegraph operated until 1983, owning all of its equipment and refusing to communicate with non-Marconi equipped ships. Many inventions improved the quality of radio, and amateurs experimented with uses of radio, thus the first seeds of broadcasting were planted.
was founded on May 27, 1903 as "Telefunken society for wireless telefon" of Siemens & Halske
(S & H) and the Allgemeine Elektrizitäts-Gesellschaft (General Electricity Company)
as joint undertakings for radio engineering in Berlin. It continued as a joint venture of AEG
and Siemens AG
, until Siemens left in 1941. In 1911, Kaiser Wilhelm II sent Telefunken engineers to West Sayville, New York
to erect three 600-foot (180-m) radio towers there. Nikola Tesla assisted in the construction. A similar station was erected in Nauen
, creating the only wireless communication between North America and Europe.
and Lee de Forest
. On Christmas Eve
1906, Reginald Fessenden
used an Alexanderson alternator
and rotary spark-gap transmitter
to make the first radio audio broadcast, from Brant Rock, Massachusetts
. Ships at sea heard a broadcast that included Fessenden playing O Holy Night
on the violin
and reading a passage from the Bible
.
and Karl Ferdinand Braun
were awarded the Nobel Prize in Physics
for "contributions to the development of wireless telegraphy".
constructed a broadcasting station. It used spark gap
technology, but modulated the carrier frequency with the human voice, and later music. The station "San Jose Calling" (there were no call letters), continued to eventually become today's KCBS
in San Francisco. Herrold, the son of a Santa Clara Valley
farmer, coined the terms "narrowcasting" and "broadcasting", respectively to identify transmissions destined for a single receiver such as that on board a ship, and those transmissions destined for a general audience. (The term "broadcasting" had been used in farming to define the tossing of seed in all directions.) Charles Herrold did not claim to be the first to transmit the human voice, but he claimed to be the first to conduct "broadcasting". To help the radio signal to spread in all directions, he designed some omnidirectional antenna
s, which he mounted on the rooftops of various buildings in San Jose. Herrold also claims to be the first broadcaster to accept advertising
(he exchanged publicity for a local record store for records to play on his station), though this dubious honour usually is foisted on WEAF
(1922).
In 1912, the RMS Titanic sank in the northern Atlantic Ocean. After this, wireless telegraphy using spark-gap transmitters quickly became universal on large ships. In 1913, the International Convention for the Safety of Life at Sea
was convened and produced a treaty requiring shipboard radio stations to be manned 24 hours a day. A typical high-power spark gap was a rotating commutator with six to twelve contacts per wheel, nine inches (229 mm) to a foot wide, driven by about 2000 volt
s DC. As the gaps made and broke contact, the radio wave was audible as a tone in a Magnetic detector
at a remote location. The telegraph key often directly made and broke the 2000 volt supply. One side of the spark gap was directly connected to the antenna. Receivers with thermionic valves became commonplace before spark-gap transmitters were replaced by continuous wave transmitters.
under the call sign 1XE (it lasted 3 hours). The company later became the first to broadcast on a daily schedule, and the first to broadcast radio dance programs, university professor lectures, the weather, and bedtime stories.
, the superheterodyne circuit and wide-band frequency modulation
or FM. Regeneration or the use of positive feedback
greatly increased the amplitude of received radio signals to the point where they could be heard without headphones. The superhet simplified radio receivers by doing away with the need for several tuning controls. It made radios more sensitive and selective as well. FM gave listeners a static-free experience with better sound quality and fidelity than AM.
The most common type of receiver before vacuum tubes was the crystal set
, although some early radios used some type of amplification through electric current or battery. Inventions of the triode amplifier, motor-generator
, and detector
enabled audio radio. The use of amplitude modulation
(AM), with which more than one station can simultaneously send signals (as opposed to spark-gap radio, where one transmitter covers the entire bandwidth of spectra) was pioneered by Fessenden and Lee de Forest
.
To this day there is a small but avid base of fans of this technology who study and practice the art and science of designing and making crystal sets as a hobby; the Boy Scouts of America have often undertaken such craft projects to introduce boys to electronics and radio, and quite a number of them having grown up remain staunch fans of a radio that 'runs on nothing, forever'. As the only energy available is that gathered by the antenna system, there are inherent limitations on how much sound even an ideal set could produce, but with only moderately decent antenna systems remarkable performance is possible with a superior set.
s (or thermionic valves in the UK) revolutionized radio receivers and transmitter
s. John Ambrose Fleming
developed an earlier tube known as an "oscillation valve" (it was a diode
). Lee De Forest
placed a screen, the "grid" electrode, between the filament and plate electrode, creating the triode
. The Dutch engineer Hanso Schotanus à Steringa Idzerda made the first regular wireless broadcast for entertainment from his home in The Hague
on 6 November 1919. He broadcast his popular program four nights per week until 1924 when he ran into financial troubles.
On 27 August 1920, regular wireless broadcasts for entertainment began in Argentina
, pioneered by the group around Enrique Telémaco Susini
, and spark gap
telegraphy stopped. On 31 August 1920 the first known radio news program was broadcast by station 8MK, the unlicensed predecessor of WWJ (AM)
in Detroit, Michigan
. In 1922 regular wireless broadcasts for entertainment began in the UK from the Marconi
Research Centre 2MT
at Writtle
near Chelmsford, England. Early radios ran the entire power of the transmitter through a carbon microphone
. In the 1920s, the Westinghouse company
bought Lee De Forest
's and Edwin Armstrong
's patent. During the mid 1920s, Amplifying vacuum tube
s (US)/thermionic valves (UK) revolutionized radio receivers and transmitter
s. Westinghouse engineers developed a more modern vacuum tube.
Broadcasting was not yet supported by advertising
or listener sponsorship. The stations owned by manufacturers and department stores were established to sell radios and those owned by newspapers to sell newspapers and express the opinions of the owners. In the 1920s, radio was first used to transmit pictures visible as television. During the early 1930s, single sideband (SSB) and frequency modulation
(FM) were invented by amateur radio operators. By 1940, they were established commercial modes.
Westinghouse was brought into the patent allies group, General Electric
, American Telephone and Telegraph, and Radio Corporation of America, and became a part owner of RCA. All radios made by GE and Westinghouse were sold under the RCA label 60% GE and 40% Westinghouse. ATT's Western Electric
would build radio transmitters. The patent allies attempted to set up a monopoly, but they failed due to successful competition. Much to the dismay of the patent allies, several of the contracts for inventor's patents held clauses protecting "amateurs" and allowing them to use the patents. Whether the competing manufacturers were really amateurs was ignored by these competitors.
These features arose:
s in broadcast networks. The earliest radio stations were simply radio telegraph systems which did not carry audio are not listed. The included first radio station encompass AM and FM stations; these include both commercial, public and nonprofit varieties found throughout the world.
Note: The first claimed audio transmission that could be termed to be from a broadcast station occurred on Christmas Eve in 1906, and was made by Reginald Fessenden.
Charles Herrold started broadcasting from a station in California in 1909 and was carrying audio by 1910.
Note: Some of the dates listed here may not be accurate. Feel free to make corrections to either of the lists.
Notes:
: Date unconfirmed.
: Broadcasts had also been available from Louisiana and Alabama since 1922.
: Broadcasts were also available from North Carolina and Georgia.
: Broadcasts were also available from Colorado since 1921.
: Radio broadcasting in Java briefly ceased after a station was destroyed by lightning.
: Broadcasts from Argentina had also been available as is the case today.
: Radio broadcasting had also been received from Italy, since Vatican City lies within the vicinity of Rome as is the case today.
: Malta had also received radio broadcasts from Italy. The British adopted a radio service on the island to counter Fascist propaganda.
: Radio broadcasts did exist in the Bahamas prior to 1936. Before then, they were received from the United States.
: Also received radio broadcasts from nearby Yugoslavia.
: Broadcasting in Aden ceased in 1946-1947 and again from 1948-1955.
: Andorra also received radio broadcasts from Spain.
: Radio broadcasts from the Trust Territory of the Pacific Islands had also been available.
: Broadcasts had also been received from Saudi Arabia and Bahrain.
: Broadcasts had previously been received from South Africa.
. FM uses frequency modulation
of the radio wave to minimize static
and interference from electrical equipment and the atmosphere, in the audio program. In 1937, W1XOJ, the first experimental FM radio station, was granted a construction permit by the U.S. Federal Communications Commission
(FCC). In the 1930s, standard analog television
transmissions started in Europe, and then in the 1940s in North America. Armstrong's FM system was designated by the FCC to transmit and receive television sound.
. Because of the recent war, Germany (which did not exist as a state and so was not invited) was only given a small number of medium-wave
frequencies, which are not very good for broadcasting. For this reason Germany began broadcasting on UKW ("Ultrakurzwelle", i.e. ultra short wave, nowadays called VHF
) which was not covered by the Copenhagen plan. After some amplitude modulation
experience with VHF, it was realized that FM radio was a much better alternative for VHF radio than AM. Because of this history FM Radio is still referred to as "UKW Radio" in Germany. Other European nations followed a bit later, when the superior sound quality of FM and the ability to run many more local stations because of the more limited range of VHF broadcasts were realized.
radio, the TR-1
, powered by a "standard 22.5V Battery". In the early 1960s, VOR
systems finally became widespread for aircraft
navigation; before that, aircraft used commercial AM radio stations for navigation. (AM stations are still marked on U.S. aviation
charts). In 1960 Sony
introduced their first transistorized radio, small enough to fit in a vest pocket, and able to be powered by a small battery. It was durable, because there were no tubes to burn out. Over the next twenty years, transistors displaced tubes almost completely except for picture tubes
and very high power or very high frequency uses.
did not go away on radio. Instead, the degree of automation increased. On land-lines in the 1930s, Teletypewriters automated encoding, and were adapted to pulse-code dialing to automate routing, a service called telex
. For thirty years, telex was the absolute cheapest form of long-distance communication, because up to 25 telex channels could occupy the same bandwidth as one voice channel. For business and government, it was an advantage that telex directly produced written documents.
Telex systems were adapted to short-wave radio by sending tones over single sideband. CCITT
R.44 (the most advanced pure-telex standard) incorporated character-level error detection and retransmission as well as automated encoding and routing. For many years, telex-on-radio (TOR) was the only reliable way to reach some third-world countries. TOR remains reliable, though less-expensive forms of e-mail are displacing it. Many national telecom companies historically ran nearly pure telex networks for their governments, and they ran many of these links over short wave radio.
Indeed, the music recording industry had a severe drop in profits after the introduction of the radio. For a while, it appeared as though radio was a definite threat to the record industry. Radio ownership grew from 2 out of 5 homes in 1931 to 4 out of 5 homes in 1938. Meanwhile record sales fell from $75 million in 1929 to $26 million in 1938 (with a low point of $5 million in 1933), though the economics of the situation were also affected by the Great Depression.
The copyright owners of these songs were concerned that they would see no gain from the popularity of radio and the ‘free’ music it provided. Luckily, everything they needed to make this new medium work for them already existed in previous copyright law. The copyright holder for a song had control over all public performances ‘for profit.’ The problem now was proving that the radio industry, which was just figuring out for itself how to make money from advertising and currently offered free music to anyone with a receiver, was making a profit from the songs.
The test case was against Bamberger Department Store in Newark, New Jersey in 1922. The store was broadcasting music throughout its store on the radio station WOR. No advertisements were heard, except for at the beginning of the broadcast which announced "L. Bamberger and Co., One of America's Great Stores, Newark, New Jersey." It was determined through this and previous cases (such as the lawsuit against Shanley's Restaurant) that Bamberger was using the songs for commercial gain, thus making it a public performance for profit, which meant the copyright owners were due payment.
With this ruling the American Society of Composers, Authors and Publishers (ASCAP) began collecting licensing fees from radio stations in 1923. The beginning sum was $230 for all music protected under ASCAP, but for larger stations the price soon ballooned up to $5,000. Edward Samuel's reports in his book The Illustrated Story of Copyright that "radio and TV licensing represents the single greatest source of revenue for ASCAP and its composers […] and average member of ASCAP gets about $150–$200 per work per year, or about $5,000-$6,000 for all of a member's compositions. Not long after the Bamberger ruling, ASCAP had to once again defend their right to charge fees in 1924. The Dill Radio Bill would have allowed radio stations to play music without paying and licensing fees to ASCAP or any other music-licensing corporations. The bill did not pass.
General
Radio equipment
Radio equipment, as defined in Federal Information Management Regulations, is any equipment or interconnected system or subsystem of equipment that is used to communicate over a distance by modulating and radiating electromagnetic waves in space without artificial guide...
that use radio wave
Radio Wave
Radio Wave may refer to:*Radio frequency*Radio Wave 96.5, a radio station in Blackpool, UK...
s. Within the timeline of radio
Timeline of radio
The timeline of radio lists within the history of radio, the technology and events that produced instruments that use radio waves and activities that people undertook...
, many people contributed theory and inventions in what became radio
Radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...
. Radio development began as "wireless telegraphy
Wireless telegraphy
Wireless telegraphy is a historical term used today to apply to early radio telegraph communications techniques and practices, particularly those used during the first three decades of radio before the term radio came into use....
". Later radio history increasingly involves matters of programming and content.
Invention
James Clerk MaxwellJames Clerk Maxwell
James Clerk Maxwell of Glenlair was a Scottish physicist and mathematician. His most prominent achievement was formulating classical electromagnetic theory. This united all previously unrelated observations, experiments and equations of electricity, magnetism and optics into a consistent theory...
showed mathematically that electromagnetic waves could propagate through free space. Heinrich Rudolf Hertz
Heinrich Rudolf Hertz
Heinrich Rudolf Hertz was a German physicist who clarified and expanded the electromagnetic theory of light that had been put forth by Maxwell...
and many others demonstrated radio wave propagation on a laboratory scale.
Transmission and radiation of radio frequency energy was a feature exhibited in the experiments by Nikola Tesla
Nikola Tesla
Nikola Tesla was a Serbian-American inventor, mechanical engineer, and electrical engineer...
, that he proposed in 1892 and 1893 might be used for the telecommunication
Telecommunication
Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...
of information
Information
Information in its most restricted technical sense is a message or collection of messages that consists of an ordered sequence of symbols, or it is the meaning that can be interpreted from such a message or collection of messages. Information can be recorded or transmitted. It can be recorded as...
. The Tesla method
Wireless energy transfer
Wireless energy transfer or wireless power is the transmission of electrical energy from a power source to an electrical load without artificial interconnecting conductors. Wireless transmission is useful in cases where interconnecting wires are inconvenient, hazardous, or impossible...
was described in New York in 1897. In 1897, Tesla applied for two key United States radio patents, , first radio system patent, and . Tesla also used sensitive electromagnetic receivers, that were unlike the less responsive coherer
Coherer
The coherer was a primitive form of radio signal detector used in the first radio receivers during the wireless telegraphy era at the beginning of the twentieth century. Invented around 1890 by French scientist Édouard Branly, it consisted of a tube or capsule containing two electrodes spaced a...
s later used by Marconi and other early experimenters. Shortly thereafter, he began to develop wireless remote control devices.
In 1895, Marconi built a wireless system capable of transmitting signals at long distances (1.5 mi./ 2.4 km). From Marconi's experiments, the phenomenon that transmission range is proportional to the square of antenna height is known as "Marconi's law
Marconi's law
Marconi's law is the relation between height of antennae and maximum signalling distance. Guglielmo Marconi enunciated at one time an empirical law that, for simple vertical sending and receiving antennae of equal height, the maximum working telegraphic distance varied as the square of the height...
". This formula represents a physical law
Physical law
A physical law or scientific law is "a theoretical principle deduced from particular facts, applicable to a defined group or class of phenomena, and expressible by the statement that a particular phenomenon always occurs if certain conditions be present." Physical laws are typically conclusions...
that radio devices use.
Early radio telegraphy and telephony
The term wireless telegraphyWireless telegraphy
Wireless telegraphy is a historical term used today to apply to early radio telegraph communications techniques and practices, particularly those used during the first three decades of radio before the term radio came into use....
is a historical term used today to apply to early radio telegraph communications techniques and practices, particularly those used during the first three decades of radio (1887 to 1920) before the term radio came into use. Guglielmo Marconi
Guglielmo Marconi
Guglielmo Marconi was an Italian inventor, known as the father of long distance radio transmission and for his development of Marconi's law and a radio telegraph system. Marconi is often credited as the inventor of radio, and indeed he shared the 1909 Nobel Prize in Physics with Karl Ferdinand...
demonstrated application of radio in commercial, military and marine communications and started a company for the development and propagation of radio communication services and equipment. The field of radio development attracted many researchers, and bitter arguments over the true "inventor of radio" persist to this day.
Turn of the 20th century
Around the turn of the centuryTurn of the century
Turn of the century, in its broadest sense, refers to the transition from one century to another. The term is most often used to indicate a non-specific time period either before or after the beginning of a century....
, the Slaby-Arco wireless system was developed by Adolf Slaby
Adolf Slaby
Adolf Karl Heinrich Slaby was a German wireless pioneer and the first Professor of electro-technology at the Technical University of Berlin .-Education:Slaby was born in Berlin, the son of a bookbinder...
and Georg von Arco
Georg von Arco
Georg Wilhelm Alexander Hans Graf von Arco was a German physicist, radio pioneer, and one of the joint founders of the "Society for Wireless Telegraphy" which became the Telefunken company. He was an engineer and the technical director of Telefunken...
. In 1900, Reginald Fessenden
Reginald Fessenden
Reginald Aubrey Fessenden , a naturalized American citizen born in Canada, was an inventor who performed pioneering experiments in radio, including early—and possibly the first—radio transmissions of voice and music...
made a weak transmission of voice over the airwaves. In 1901, Marconi conducted the first successful transatlantic experimental radio communications. In 1904, The U.S. Patent Office
United States Patent and Trademark Office
The United States Patent and Trademark Office is an agency in the United States Department of Commerce that issues patents to inventors and businesses for their inventions, and trademark registration for product and intellectual property identification.The USPTO is based in Alexandria, Virginia,...
reversed its decision, awarding Marconi a patent for the invention of radio, possibly influenced by Marconi's financial backers in the States, who included Thomas Edison
Thomas Edison
Thomas Alva Edison was an American inventor and businessman. He developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and a long-lasting, practical electric light bulb. In addition, he created the world’s first industrial...
and Andrew Carnegie
Andrew Carnegie
Andrew Carnegie was a Scottish-American industrialist, businessman, and entrepreneur who led the enormous expansion of the American steel industry in the late 19th century...
. This also allowed the U.S. government (among others) to avoid having to pay the royalties that were being claimed by Tesla for use of his patents. For more information see Marconi's radio work. In 1907, Marconi established the first commercial transatlantic radio communications service, between Clifden
Clifden
Clifden is a town on the coast of County Galway, Ireland and being Connemara's largest town, it is often referred to as "the Capital of Connemara". It is located on the Owenglen River where it flows into Clifden Bay...
, Ireland and Glace Bay, Newfoundland
Dominion of Newfoundland
The Dominion of Newfoundland was a British Dominion from 1907 to 1949 . The Dominion of Newfoundland was situated in northeastern North America along the Atlantic coast and comprised the island of Newfoundland and Labrador on the continental mainland...
.
Julio Cervera Baviera
Julio Cervera Baviera
Julio Cervera Baviera was a Spanish engineer, pioneer in the development of radio, educator, explorer, and military man. He also authored various scientific and geographic books and articles.-Education:...
developed radio in Spain around 1902.
Cervera Baviera obtained patents in England, Germany, Belgium, and Spain. In May–June 1899, Cervera had, with the blessing of the Spanish Army
Spanish Army
The Spanish Army is the terrestrial army of the Spanish Armed Forces responsible for land-based military operations. It is one of the oldest active armies - dating back to the 15th century.-Introduction:...
, visited Marconi's radiotelegraphic installations on the English Channel
English Channel
The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...
, and worked to develop his own system. He began collaborating with Marconi on resolving the problem of a wireless communication system, obtaining some patents by the end of 1899. Cervera, who had worked with Marconi and his assistant George Kemp
George Kemp
George Kemp may refer to:* George Stephen Kemp, Electrical engineer and assistant to Guglielmo Marconi* George Meikle Kemp , Scottish carpenter/joiner, draughtsman, and self-taught architect...
in 1899, resolved the difficulties of wireless telegraph and obtained his first patents prior to the end of that year. On March 22, 1902, Cervera founded the Spanish Wireless Telegraph and Telephone Corporation and brought to his corporation the patents he had obtained in Spain, Belgium, Germany and England. He established the second and third regular radiotelegraph service in the history of the world in 1901 and 1902 by maintaining regular transmissions between Tarifa
Tarifa
Tarifa is a small town in the province of Cádiz, Andalusia, on the southernmost coast of Spain. The town is located on the Costa de la Luz and across the Straits of Gibraltar facing Morocco. The municipality includes Punta de Tarifa, the southernmost point in continental Europe. There are five...
and Ceuta
Ceuta
Ceuta is an autonomous city of Spain and an exclave located on the north coast of North Africa surrounded by Morocco. Separated from the Iberian peninsula by the Strait of Gibraltar, Ceuta lies on the border of the Mediterranean Sea and the Atlantic Ocean. Ceuta along with the other Spanish...
for three consecutive months, and between Javea (Cabo de la Nao) and Ibiza
Ibiza
Ibiza or Eivissa is a Spanish island in the Mediterranean Sea 79 km off the coast of the city of Valencia in Spain. It is the third largest of the Balearic Islands, an autonomous community of Spain. With Formentera, it is one of the two Pine Islands or Pityuses. Its largest cities are Ibiza...
(Cabo Pelado). This is after Marconi established the radiotelegraphic service between the Isle of Wight
Isle of Wight
The Isle of Wight is a county and the largest island of England, located in the English Channel, on average about 2–4 miles off the south coast of the county of Hampshire, separated from the mainland by a strait called the Solent...
and Bournemouth
Bournemouth
Bournemouth is a large coastal resort town in the ceremonial county of Dorset, England. According to the 2001 Census the town has a population of 163,444, making it the largest settlement in Dorset. It is also the largest settlement between Southampton and Plymouth...
in 1898. In 1906, Domenico Mazzotto wrote: "In Spain the Minister of War has applied the system perfected by the commander of military engineering, Julio Cervera Baviera (English patent No. 20084 (1899))." Cervera thus achieved some success in this field, but his radiotelegraphic activities ceased suddenly, the reasons for which are unclear to this day.
British Marconi
Using various patentPatent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
s, the company called British Marconi
Marconi Company
The Marconi Company Ltd. was founded by Guglielmo Marconi in 1897 as The Wireless Telegraph & Signal Company...
was established in 1897 and began communication between coast radio station
Coast radio station
A coast radio station is an on-shore maritime radio station which monitors radio distress frequencies and relays ship-to-ship and ship-to-land communications.-See also:* Marconi Station* Utility station...
s and ships at sea. This company along with its subsidiary American Marconi, had a stranglehold on ship to shore communication. It operated much the way American Telephone and Telegraph operated until 1983, owning all of its equipment and refusing to communicate with non-Marconi equipped ships. Many inventions improved the quality of radio, and amateurs experimented with uses of radio, thus the first seeds of broadcasting were planted.
Telefunken
The company TelefunkenTelefunken
Telefunken is a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the Allgemeine Elektricitäts-Gesellschaft...
was founded on May 27, 1903 as "Telefunken society for wireless telefon" of Siemens & Halske
Siemens & Halske
Siemens & Halske AG was a German electrical engineering company that later became part of Siemens AG.It was founded on 12 October 1847 as Telegraphen-Bauanstalt von Siemens & Halske by Ernst Werner von Siemens and Johann Georg Halske...
(S & H) and the Allgemeine Elektrizitäts-Gesellschaft (General Electricity Company)
AEG
Allgemeine Elektricitäts-Gesellschaft was a German producer of electrical equipment founded in 1883 by Emil Rathenau....
as joint undertakings for radio engineering in Berlin. It continued as a joint venture of AEG
AEG
Allgemeine Elektricitäts-Gesellschaft was a German producer of electrical equipment founded in 1883 by Emil Rathenau....
and Siemens AG
Siemens AG
Siemens AG is a German multinational conglomerate company headquartered in Munich, Germany. It is the largest Europe-based electronics and electrical engineering company....
, until Siemens left in 1941. In 1911, Kaiser Wilhelm II sent Telefunken engineers to West Sayville, New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
to erect three 600-foot (180-m) radio towers there. Nikola Tesla assisted in the construction. A similar station was erected in Nauen
Nauen
Nauen is a town in the Havelland district, in Brandenburg, Germany. It is situated 38 km west of Berlin and 26 km northwest of Potsdam.-History:...
, creating the only wireless communication between North America and Europe.
Reginald Fessenden
The invention of amplitude-modulated (AM) radio, so that more than one station can send signals (as opposed to spark-gap radio, where one transmitter covers the entire bandwidth of the spectrum) is attributed to Reginald FessendenReginald Fessenden
Reginald Aubrey Fessenden , a naturalized American citizen born in Canada, was an inventor who performed pioneering experiments in radio, including early—and possibly the first—radio transmissions of voice and music...
and Lee de Forest
Lee De Forest
Lee De Forest was an American inventor with over 180 patents to his credit. De Forest invented the Audion, a vacuum tube that takes relatively weak electrical signals and amplifies them. De Forest is one of the fathers of the "electronic age", as the Audion helped to usher in the widespread use...
. On Christmas Eve
Christmas Eve
Christmas Eve refers to the evening or entire day preceding Christmas Day, a widely celebrated festival commemorating the birth of Jesus of Nazareth that takes place on December 25...
1906, Reginald Fessenden
Reginald Fessenden
Reginald Aubrey Fessenden , a naturalized American citizen born in Canada, was an inventor who performed pioneering experiments in radio, including early—and possibly the first—radio transmissions of voice and music...
used an Alexanderson alternator
Alexanderson alternator
An Alexanderson alternator is a rotating machine invented by Ernst Alexanderson in 1904 for the generation of high frequency alternating current up to 100 kHz, for use as a radio transmitter...
and rotary spark-gap transmitter
Spark-gap transmitter
A spark-gap transmitter is a device for generating radio frequency electromagnetic waves using a spark gap.These devices served as the transmitters for most wireless telegraphy systems for the first three decades of radio and the first demonstrations of practical radio were carried out using them...
to make the first radio audio broadcast, from Brant Rock, Massachusetts
Ocean Bluff-Brant Rock, Massachusetts
Ocean Bluff-Brant Rock is a census-designated place in Plymouth County, Massachusetts, United States, composed of the villages of Ocean Bluff and Brant Rock in the town of Marshfield...
. Ships at sea heard a broadcast that included Fessenden playing O Holy Night
O Holy Night
"O Holy Night" is a well-known Christmas carol composed by Adolphe Adam in 1847 to the French poem "Minuit, chrétiens" by Placide Cappeau , a wine merchant and poet, who had been asked by a parish priest to write a Christmas poem...
on the violin
Violin
The violin is a string instrument, usually with four strings tuned in perfect fifths. It is the smallest, highest-pitched member of the violin family of string instruments, which includes the viola and cello....
and reading a passage from the Bible
Bible
The Bible refers to any one of the collections of the primary religious texts of Judaism and Christianity. There is no common version of the Bible, as the individual books , their contents and their order vary among denominations...
.
Ferdinand Braun
In 1909, MarconiGuglielmo Marconi
Guglielmo Marconi was an Italian inventor, known as the father of long distance radio transmission and for his development of Marconi's law and a radio telegraph system. Marconi is often credited as the inventor of radio, and indeed he shared the 1909 Nobel Prize in Physics with Karl Ferdinand...
and Karl Ferdinand Braun
Karl Ferdinand Braun
Karl Ferdinand Braun was a German inventor, physicist and Nobel laureate in physics. Braun contributed significantly to the development of the radio and television technology: he shared with Guglielmo Marconi the 1909 Nobel Prize in Physics.-Biography:Braun was born in Fulda, Germany, and...
were awarded the Nobel Prize in Physics
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...
for "contributions to the development of wireless telegraphy".
Charles David Herrold
In April 1909 Charles David Herrold, an electronics instructor in San Jose, CaliforniaSan Jose, California
San Jose is the third-largest city in California, the tenth-largest in the U.S., and the county seat of Santa Clara County which is located at the southern end of San Francisco Bay...
constructed a broadcasting station. It used spark gap
Spark gap
A spark gap consists of an arrangement of two conducting electrodes separated by a gap usually filled with a gas such as air, designed to allow an electric spark to pass between the conductors. When the voltage difference between the conductors exceeds the gap's breakdown voltage, a spark forms,...
technology, but modulated the carrier frequency with the human voice, and later music. The station "San Jose Calling" (there were no call letters), continued to eventually become today's KCBS
KCBS (AM)
KCBS is an all-news radio station in San Francisco, California, that is a key West Coast flagship radio station of the CBS Radio Network and Westwood One. Its transmitter is located in Novato, California. KCBS currently has studios on Battery Street, where it shares the location with co-owned KPIX...
in San Francisco. Herrold, the son of a Santa Clara Valley
Santa Clara Valley
The Santa Clara Valley is a valley just south of the San Francisco Bay in Northern California in the United States. Much of Santa Clara County and its county seat, San José, are in the Santa Clara Valley. The valley was originally known as the Valley of Heart’s Delight for its high concentration...
farmer, coined the terms "narrowcasting" and "broadcasting", respectively to identify transmissions destined for a single receiver such as that on board a ship, and those transmissions destined for a general audience. (The term "broadcasting" had been used in farming to define the tossing of seed in all directions.) Charles Herrold did not claim to be the first to transmit the human voice, but he claimed to be the first to conduct "broadcasting". To help the radio signal to spread in all directions, he designed some omnidirectional antenna
Omnidirectional antenna
In radio communication, an omnidirectional antenna is an antenna which radiates radio wave power uniformly in all directions in one plane, with the radiated power decreasing with elevation angle above or below the plane, dropping to zero on the antenna's axis. This radiation pattern is often...
s, which he mounted on the rooftops of various buildings in San Jose. Herrold also claims to be the first broadcaster to accept advertising
Advertising
Advertising is a form of communication used to persuade an audience to take some action with respect to products, ideas, or services. Most commonly, the desired result is to drive consumer behavior with respect to a commercial offering, although political and ideological advertising is also common...
(he exchanged publicity for a local record store for records to play on his station), though this dubious honour usually is foisted on WEAF
WEAF (AM)
WEAF is a gospel music formatted radio station in Camden, South Carolina. The station is currently owned by Colonial Radio Group and is licensed to CRG president Jeff Andrulonis. Much of the programing is featured from the Rejoice! Musical Soul Food satellite feed.-History:At one time, this...
(1922).
International Convention for the Safety of Life at Sea
The International Convention for the Safety of Life at Sea is an international maritime safety treaty. The SOLAS Convention in its successive forms is generally regarded as the most important of all international treaties concerning the safety of merchant ships.- History :The first version of the...
was convened and produced a treaty requiring shipboard radio stations to be manned 24 hours a day. A typical high-power spark gap was a rotating commutator with six to twelve contacts per wheel, nine inches (229 mm) to a foot wide, driven by about 2000 volt
Volt
The volt is the SI derived unit for electric potential, electric potential difference, and electromotive force. The volt is named in honor of the Italian physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery.- Definition :A single volt is defined as the...
s DC. As the gaps made and broke contact, the radio wave was audible as a tone in a Magnetic detector
Magnetic detector
The magnetic detector was one of the first practical devices able to make radio signals audible through a pair of headphones. It was not as sensitive as some detectors but despite that, it was favored for early maritime use because of its reliability....
at a remote location. The telegraph key often directly made and broke the 2000 volt supply. One side of the spark gap was directly connected to the antenna. Receivers with thermionic valves became commonplace before spark-gap transmitters were replaced by continuous wave transmitters.
Harold J. Power
On March 8, 1916, Harold Power with his radio company American Radio and Research Company (AMRAD), broadcast the first continuous broadcast in the world from Tufts UniversityTufts University
Tufts University is a private research university located in Medford/Somerville, near Boston, Massachusetts. It is organized into ten schools, including two undergraduate programs and eight graduate divisions, on four campuses in Massachusetts and on the eastern border of France...
under the call sign 1XE (it lasted 3 hours). The company later became the first to broadcast on a daily schedule, and the first to broadcast radio dance programs, university professor lectures, the weather, and bedtime stories.
Edwin Armstrong
Inventor Edwin Howard Armstrong is credited with developing many of the features of radio as it is known today. Armstrong patented three important inventions that made today's radio possible. RegenerationRegenerative circuit
The regenerative circuit or "autodyne" allows an electronic signal to be amplified many times by the same vacuum tube or other active component such as a field effect transistor. It consists of an amplifying vacuum tube or transistor with its output connected to its input through a feedback...
, the superheterodyne circuit and wide-band frequency modulation
Frequency modulation
In telecommunications and signal processing, frequency modulation conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant...
or FM. Regeneration or the use of positive feedback
Positive feedback
Positive feedback is a process in which the effects of a small disturbance on a system include an increase in the magnitude of the perturbation. That is, A produces more of B which in turn produces more of A. In contrast, a system that responds to a perturbation in a way that reduces its effect is...
greatly increased the amplitude of received radio signals to the point where they could be heard without headphones. The superhet simplified radio receivers by doing away with the need for several tuning controls. It made radios more sensitive and selective as well. FM gave listeners a static-free experience with better sound quality and fidelity than AM.
Crystal sets
Crystal radio receiver
thumb|Boy listening to a modern crystal radioA crystal radio receiver, also called a crystal set or cat's whisker receiver, is a very simple radio receiver, popular in the early days of radio. It needs no battery or power source and runs on the power received from radio waves by a long wire antenna...
, although some early radios used some type of amplification through electric current or battery. Inventions of the triode amplifier, motor-generator
Motor-generator
A motor-generator is a device for converting electrical power to another form. Motor-generator sets are used to convert frequency, voltage, or phase of power. They may also be used to isolate electrical loads from the electrical power supply line...
, and detector
Detector (radio)
A detector is a device that recovers information of interest contained in a modulated wave. The term dates from the early days of radio when all transmissions were in Morse code, and it was only necessary to detect the presence of a radio wave using a device such as a coherer without necessarily...
enabled audio radio. The use of amplitude modulation
Amplitude modulation
Amplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
(AM), with which more than one station can simultaneously send signals (as opposed to spark-gap radio, where one transmitter covers the entire bandwidth of spectra) was pioneered by Fessenden and Lee de Forest
Lee De Forest
Lee De Forest was an American inventor with over 180 patents to his credit. De Forest invented the Audion, a vacuum tube that takes relatively weak electrical signals and amplifies them. De Forest is one of the fathers of the "electronic age", as the Audion helped to usher in the widespread use...
.
To this day there is a small but avid base of fans of this technology who study and practice the art and science of designing and making crystal sets as a hobby; the Boy Scouts of America have often undertaken such craft projects to introduce boys to electronics and radio, and quite a number of them having grown up remain staunch fans of a radio that 'runs on nothing, forever'. As the only energy available is that gathered by the antenna system, there are inherent limitations on how much sound even an ideal set could produce, but with only moderately decent antenna systems remarkable performance is possible with a superior set.
The first vacuum tubes
During the mid 1920s, amplifying vacuum tubeVacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
s (or thermionic valves in the UK) revolutionized radio receivers and transmitter
Transmitter
In electronics and telecommunications a transmitter or radio transmitter is an electronic device which, with the aid of an antenna, produces radio waves. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating...
s. John Ambrose Fleming
John Ambrose Fleming
Sir John Ambrose Fleming was an English electrical engineer and physicist. He is known for inventing the first thermionic valve or vacuum tube, the diode, then called the kenotron in 1904. He is also famous for the left hand rule...
developed an earlier tube known as an "oscillation valve" (it was a diode
Diode
In electronics, a diode is a type of two-terminal electronic component with a nonlinear current–voltage characteristic. A semiconductor diode, the most common type today, is a crystalline piece of semiconductor material connected to two electrical terminals...
). Lee De Forest
Lee De Forest
Lee De Forest was an American inventor with over 180 patents to his credit. De Forest invented the Audion, a vacuum tube that takes relatively weak electrical signals and amplifies them. De Forest is one of the fathers of the "electronic age", as the Audion helped to usher in the widespread use...
placed a screen, the "grid" electrode, between the filament and plate electrode, creating the triode
Triode
A triode is an electronic amplification device having three active electrodes. The term most commonly applies to a vacuum tube with three elements: the filament or cathode, the grid, and the plate or anode. The triode vacuum tube was the first electronic amplification device...
. The Dutch engineer Hanso Schotanus à Steringa Idzerda made the first regular wireless broadcast for entertainment from his home in The Hague
The Hague
The Hague is the capital city of the province of South Holland in the Netherlands. With a population of 500,000 inhabitants , it is the third largest city of the Netherlands, after Amsterdam and Rotterdam...
on 6 November 1919. He broadcast his popular program four nights per week until 1924 when he ran into financial troubles.
On 27 August 1920, regular wireless broadcasts for entertainment began in Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
, pioneered by the group around Enrique Telémaco Susini
Enrique Telémaco Susini
Enrique Telémaco Susini was an Argentine entrepreneur and media pioneer.In 1920, Susini led the effort for the first radio broadcast in Argentina, and subsequently established one of the earliest regular radio stations in the world...
, and spark gap
Spark gap
A spark gap consists of an arrangement of two conducting electrodes separated by a gap usually filled with a gas such as air, designed to allow an electric spark to pass between the conductors. When the voltage difference between the conductors exceeds the gap's breakdown voltage, a spark forms,...
telegraphy stopped. On 31 August 1920 the first known radio news program was broadcast by station 8MK, the unlicensed predecessor of WWJ (AM)
WWJ (AM)
WWJ is Detroit, Michigan's only 24-hour all-news radio station. Broadcasting at 950 kHz, the station is owned and operated by CBS Corporation subsidiary CBS Radio. The station first went on the air on August 20, 1920 with the call sign 8MK...
in Detroit, Michigan
Detroit, Michigan
Detroit is the major city among the primary cultural, financial, and transportation centers in the Metro Detroit area, a region of 5.2 million people. As the seat of Wayne County, the city of Detroit is the largest city in the U.S. state of Michigan and serves as a major port on the Detroit River...
. In 1922 regular wireless broadcasts for entertainment began in the UK from the Marconi
Guglielmo Marconi
Guglielmo Marconi was an Italian inventor, known as the father of long distance radio transmission and for his development of Marconi's law and a radio telegraph system. Marconi is often credited as the inventor of radio, and indeed he shared the 1909 Nobel Prize in Physics with Karl Ferdinand...
Research Centre 2MT
2MT
2MT was the first British radio station to make regular entertainment broadcasts.Transmissions began on 14 February 1922 from an ex-Army hut next to the Marconi laboratories at Writtle, near Chelmsford in Essex...
at Writtle
Writtle
The village of Writtle lies a mile west of Chelmsford, Essex, England, it has a traditional village green, complete with duck pond and a Norman church; and was once described as: 'one of the loveliest villages in England, with a ravishing variety of ancient cottages'...
near Chelmsford, England. Early radios ran the entire power of the transmitter through a carbon microphone
Carbon microphone
The carbon microphone, also known as a carbon button microphone or a carbon transmitter, is a sound-to-electrical signal transducer consisting of two metal plates separated by granules of carbon. One plate faces outward and acts as a diaphragm...
. In the 1920s, the Westinghouse company
Westinghouse Electric (1886)
Westinghouse Electric was an American manufacturing company. It was founded in 1886 as Westinghouse Electric Company and later renamed Westinghouse Electric Corporation by George Westinghouse. The company purchased CBS in 1995 and became CBS Corporation in 1997...
bought Lee De Forest
Lee De Forest
Lee De Forest was an American inventor with over 180 patents to his credit. De Forest invented the Audion, a vacuum tube that takes relatively weak electrical signals and amplifies them. De Forest is one of the fathers of the "electronic age", as the Audion helped to usher in the widespread use...
's and Edwin Armstrong
Edwin Armstrong
Edwin Howard Armstrong was an American electrical engineer and inventor. Armstrong was the inventor of modern frequency modulation radio....
's patent. During the mid 1920s, Amplifying vacuum tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
s (US)/thermionic valves (UK) revolutionized radio receivers and transmitter
Transmitter
In electronics and telecommunications a transmitter or radio transmitter is an electronic device which, with the aid of an antenna, produces radio waves. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating...
s. Westinghouse engineers developed a more modern vacuum tube.
Licensed commercial public radio stations
The question of the 'first' publicly-targeted licensed radio station in the U.S. has more than one answer and depends on semantics. Settlement of this 'first' question may hang largely upon what constitutes 'regular' programming.- It is commonly attributed to KDKAKDKA (AM)KDKA is a radio station licensed to Pittsburgh, Pennsylvania, USA. Created by the Westinghouse Electric Corporation on November 2, 1920, it is one of the world's first modern radio stations , a distinction that has also been challenged by other stations, although it has claimed to be the first in...
in Pittsburgh, PennsylvaniaPittsburgh, PennsylvaniaPittsburgh is the second-largest city in the US Commonwealth of Pennsylvania and the county seat of Allegheny County. Regionally, it anchors the largest urban area of Appalachia and the Ohio River Valley, and nationally, it is the 22nd-largest urban area in the United States...
, which in October 1920 received its license and went on the air as the first US licensed commercial broadcasting station. (Their engineer Frank ConradFrank ConradFrank Conrad was a radio broadcasting pioneer who worked as the Assistant Chief Engineer for the Westinghouse Electric Corporation in Pittsburgh, Pennsylvania,...
had been broadcasting from his own station since 1916.) Technically, KDKA was the first of several already-extant stations to receive a 'limited commercial' license. - On February 17, 1919, station 9XM at the University of WisconsinUniversity of Wisconsin–MadisonThe University of Wisconsin–Madison is a public research university located in Madison, Wisconsin, United States. Founded in 1848, UW–Madison is the flagship campus of the University of Wisconsin System. It became a land-grant institution in 1866...
in MadisonMadison, WisconsinMadison is the capital of the U.S. state of Wisconsin and the county seat of Dane County. It is also home to the University of Wisconsin–Madison....
broadcast human speech to the public at large. 9XM was first experimentally licensed in 1914, began regular Morse codeMorse codeMorse code is a method of transmitting textual information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment...
transmissions in 1916, and its first music broadcast in 1917. Regularly scheduled broadcasts of voice and music began in January 1921. That station is still on the air today as WHAWHA (AM)-External links:*Jeff Miller . *Randall Davidson. PortalWisconsin.org...
. - On August 20, 1920, at least two months before KDKA, E.W. Scripps's WBL (now WWJWWJ (AM)WWJ is Detroit, Michigan's only 24-hour all-news radio station. Broadcasting at 950 kHz, the station is owned and operated by CBS Corporation subsidiary CBS Radio. The station first went on the air on August 20, 1920 with the call sign 8MK...
) in Detroit started broadcasting. It has carried a regular schedule of programming to the present. - There is the history noted above of Charles David Herrold's radio services (eventually KCBSKCBS (AM)KCBS is an all-news radio station in San Francisco, California, that is a key West Coast flagship radio station of the CBS Radio Network and Westwood One. Its transmitter is located in Novato, California. KCBS currently has studios on Battery Street, where it shares the location with co-owned KPIX...
) going back to 1909.
Broadcasting was not yet supported by advertising
Advertising
Advertising is a form of communication used to persuade an audience to take some action with respect to products, ideas, or services. Most commonly, the desired result is to drive consumer behavior with respect to a commercial offering, although political and ideological advertising is also common...
or listener sponsorship. The stations owned by manufacturers and department stores were established to sell radios and those owned by newspapers to sell newspapers and express the opinions of the owners. In the 1920s, radio was first used to transmit pictures visible as television. During the early 1930s, single sideband (SSB) and frequency modulation
Frequency modulation
In telecommunications and signal processing, frequency modulation conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant...
(FM) were invented by amateur radio operators. By 1940, they were established commercial modes.
Westinghouse was brought into the patent allies group, General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
, American Telephone and Telegraph, and Radio Corporation of America, and became a part owner of RCA. All radios made by GE and Westinghouse were sold under the RCA label 60% GE and 40% Westinghouse. ATT's Western Electric
Western Electric
Western Electric Company was an American electrical engineering company, the manufacturing arm of AT&T from 1881 to 1995. It was the scene of a number of technological innovations and also some seminal developments in industrial management...
would build radio transmitters. The patent allies attempted to set up a monopoly, but they failed due to successful competition. Much to the dismay of the patent allies, several of the contracts for inventor's patents held clauses protecting "amateurs" and allowing them to use the patents. Whether the competing manufacturers were really amateurs was ignored by these competitors.
These features arose:
- Commercial (United States) or governmental (Europe) station networks
- Federal Radio CommissionFederal Radio CommissionThe Federal Radio Commission was a government body that regulated radio use in the United States from its creation in 1926 until its replacement by the Federal Communications Commission in 1934...
- Federal Communications CommissionFederal Communications CommissionThe Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...
- CCIR
- Birth of the soap operaSoap operaA soap opera, sometimes called "soap" for short, is an ongoing, episodic work of dramatic fiction presented in serial format on radio or as television programming. The name soap opera stems from the original dramatic serials broadcast on radio that had soap manufacturers, such as Procter & Gamble,...
- Race towards shorter waves and FM
Dates of first radio stations
This is a listing of radio stationRadio station
Radio broadcasting is a one-way wireless transmission over radio waves intended to reach a wide audience. Stations can be linked in radio networks to broadcast a common radio format, either in broadcast syndication or simulcast or both...
s in broadcast networks. The earliest radio stations were simply radio telegraph systems which did not carry audio are not listed. The included first radio station encompass AM and FM stations; these include both commercial, public and nonprofit varieties found throughout the world.
Note: The first claimed audio transmission that could be termed to be from a broadcast station occurred on Christmas Eve in 1906, and was made by Reginald Fessenden.
Charles Herrold started broadcasting from a station in California in 1909 and was carrying audio by 1910.
Note: Some of the dates listed here may not be accurate. Feel free to make corrections to either of the lists.
US and Canadian territories
This list details the advent of radio in the United States and Canada.| State | Date |
|---|---|
| US Alabama Alabama Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland... |
1922 |
| US Territory of Alaska | 1924 |
| CAN Alberta Alberta Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces... |
1922 |
| US Arizona Arizona Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix... |
1922 |
| US Arkansas Arkansas Arkansas is a state located in the southern region of the United States. Its name is an Algonquian name of the Quapaw Indians. Arkansas shares borders with six states , and its eastern border is largely defined by the Mississippi River... |
1920 |
| CAN British Columbia British Columbia British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858... |
1922 |
| US California California California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area... |
1921 |
| US Colorado Colorado Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains... |
1921 |
| US Connecticut Connecticut Connecticut is a state in the New England region of the northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, and the state of New York to the west and the south .Connecticut is named for the Connecticut River, the major U.S. river that approximately... |
1922 |
| US Delaware Delaware Delaware is a U.S. state located on the Atlantic Coast in the Mid-Atlantic region of the United States. It is bordered to the south and west by Maryland, and to the north by Pennsylvania... |
1922 |
| US Florida Florida Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it... |
1921 |
| US Georgia Georgia (U.S. state) Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788... |
1922 |
| US Guam Guam Guam is an organized, unincorporated territory of the United States located in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Guam is listed as one of 16 Non-Self-Governing Territories by the Special Committee on Decolonization of the United... |
1954 |
| US Territory of Hawaii Territory of Hawaii The Territory of Hawaii or Hawaii Territory was an organized incorporated territory of the United States that existed from July 7, 1898, until August 21, 1959, when its territory, with the exception of Johnston Atoll, was admitted to the Union as the fiftieth U.S. state, the State of Hawaii.The U.S... |
1922 |
| US Idaho Idaho Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state.... |
1922 |
| US Illinois Illinois Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,... |
1921 |
| US Indiana Indiana Indiana is a US state, admitted to the United States as the 19th on December 11, 1816. It is located in the Midwestern United States and Great Lakes Region. With 6,483,802 residents, the state is ranked 15th in population and 16th in population density. Indiana is ranked 38th in land area and is... |
1921 |
| US Iowa Iowa Iowa is a state located in the Midwestern United States, an area often referred to as the "American Heartland". It derives its name from the Ioway people, one of the many American Indian tribes that occupied the state at the time of European exploration. Iowa was a part of the French colony of New... |
1922 |
| US Kansas Kansas Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south... |
1922 |
| US Kentucky Kentucky The Commonwealth of Kentucky is a state located in the East Central United States of America. As classified by the United States Census Bureau, Kentucky is a Southern state, more specifically in the East South Central region. Kentucky is one of four U.S. states constituted as a commonwealth... |
1922 |
| US Louisiana Louisiana Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties... |
1922 |
| US Maine Maine Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost... |
1922 |
| CAN Manitoba Manitoba Manitoba is a Canadian prairie province with an area of . The province has over 110,000 lakes and has a largely continental climate because of its flat topography. Agriculture, mostly concentrated in the fertile southern and western parts of the province, is vital to the province's economy; other... |
1922 |
| US Maryland Maryland Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east... |
1922 |
| US Massachusetts Massachusetts The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010... |
1920 |
| US Michigan Michigan Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake".... |
1920 |
| US Minnesota Minnesota Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state... |
1922 |
| US Mississippi Mississippi Mississippi is a U.S. state located in the Southern United States. Jackson is the state capital and largest city. The name of the state derives from the Mississippi River, which flows along its western boundary, whose name comes from the Ojibwe word misi-ziibi... |
1925 |
| US Missouri Missouri Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It... |
1921 |
| US Montana Montana Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,... |
1922 |
| US Nebraska Nebraska Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River.... |
1921 |
| US Nevada Nevada Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its... |
1922 |
| CAN New Brunswick New Brunswick New Brunswick is one of Canada's three Maritime provinces and is the only province in the federation that is constitutionally bilingual . The provincial capital is Fredericton and Saint John is the most populous city. Greater Moncton is the largest Census Metropolitan Area... |
1923 |
| US New Hampshire New Hampshire New Hampshire is a state in the New England region of the northeastern United States of America. The state was named after the southern English county of Hampshire. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Atlantic Ocean to the east, and the Canadian... |
1922 |
| US New Jersey New Jersey New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware... |
1921 |
| US New Mexico New Mexico New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S... |
1922 |
| US New York New York New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east... |
1922 |
| US North Carolina North Carolina North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte... |
1922 |
| US North Dakota North Dakota North Dakota is a state located in the Midwestern region of the United States of America, along the Canadian border. The state is bordered by Canada to the north, Minnesota to the east, South Dakota to the south and Montana to the west. North Dakota is the 19th-largest state by area in the U.S.... |
1922 |
| CAN Northwest Territories Northwest Territories The Northwest Territories is a federal territory of Canada.Located in northern Canada, the territory borders Canada's two other territories, Yukon to the west and Nunavut to the east, and three provinces: British Columbia to the southwest, and Alberta and Saskatchewan to the south... |
1958 |
| CAN Nova Scotia Nova Scotia Nova Scotia is one of Canada's three Maritime provinces and is the most populous province in Atlantic Canada. The name of the province is Latin for "New Scotland," but "Nova Scotia" is the recognized, English-language name of the province. The provincial capital is Halifax. Nova Scotia is the... |
1920 |
| US Ohio Ohio Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus... |
1922 |
| US Oklahoma Oklahoma Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state... |
1921 |
| CAN Ontario Ontario Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa.... |
1922 |
| US Oregon Oregon Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern... |
1922 |
| US Panama Canal Zone Panama Canal Zone The Panama Canal Zone was a unorganized U.S. territory located within the Republic of Panama, consisting of the Panama Canal and an area generally extending 5 miles on each side of the centerline, but excluding Panama City and Colón, which otherwise would have been partly within the limits of... |
1923 |
| US Pennsylvania Pennsylvania The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to... |
1920 |
| CAN Prince Edward Island Prince Edward Island Prince Edward Island is a Canadian province consisting of an island of the same name, as well as other islands. The maritime province is the smallest in the nation in both land area and population... |
1924 |
| US Puerto Rico Puerto Rico Puerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an... |
1922 |
| CAN Quebec Quebec Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level.... |
1920 |
| US Rhode Island Rhode Island The state of Rhode Island and Providence Plantations, more commonly referred to as Rhode Island , is a state in the New England region of the United States. It is the smallest U.S. state by area... |
1922 |
| CAN Saskatchewan Saskatchewan Saskatchewan is a prairie province in Canada, which has an area of . Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota.... |
1922 |
| US South Carolina South Carolina South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence... |
1930 |
| US South Dakota South Dakota South Dakota is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux American Indian tribes. Once a part of Dakota Territory, South Dakota became a state on November 2, 1889. The state has an area of and an estimated population of just over... |
1922 |
| US Tennessee Tennessee Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area... |
1922 |
| US Texas Texas Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in... |
1920 |
| US Utah Utah Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the... |
1922 |
| US Vermont Vermont Vermont is a state in the New England region of the northeastern United States of America. The state ranks 43rd in land area, , and 45th in total area. Its population according to the 2010 census, 630,337, is the second smallest in the country, larger only than Wyoming. It is the only New England... |
1920 |
| US Virginia Virginia The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there... |
1923 |
| US Washington | 1920 |
| US Washington, D.C. Washington, D.C. Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution.... |
1923 |
| US West Virginia West Virginia West Virginia is a state in the Appalachian and Southeastern regions of the United States, bordered by Virginia to the southeast, Kentucky to the southwest, Ohio to the northwest, Pennsylvania to the northeast and Maryland to the east... |
1923 |
| US Wisconsin Wisconsin Wisconsin is a U.S. state located in the north-central United States and is part of the Midwest. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. Wisconsin's capital is... |
1922 |
| US Wyoming Wyoming Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High... |
1930 |
| CAN Yukon Territory | 1923 |
Other countries
This list includes all other countries except the United States and Canada.| Country | Date |
|---|---|
| Netherlands Netherlands The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders... |
1919 |
| Argentina Argentina Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires... |
1920 |
| Malaya British Malaya British Malaya loosely described a set of states on the Malay Peninsula and the Island of Singapore that were brought under British control between the 18th and the 20th centuries... |
1921 |
| Mexico | 1921 |
| New Zealand | 1921 |
| Russia | 1921 |
| Uruguay Uruguay Uruguay ,officially the Oriental Republic of Uruguay,sometimes the Eastern Republic of Uruguay; ) is a country in the southeastern part of South America. It is home to some 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area... |
1921 |
| Ceylon | 1922 |
| France France The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France... |
1921 |
| Switzerland | 1922 |
| United Kingdom United Kingdom The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages... |
1922 |
| Chile Chile Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far... |
1922 |
| Cuba Cuba The Republic of Cuba is an island nation in the Caribbean. The nation of Cuba consists of the main island of Cuba, the Isla de la Juventud, and several archipelagos. Havana is the largest city in Cuba and the country's capital. Santiago de Cuba is the second largest city... |
1922 |
| Panama Panama Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The... |
1922 |
| Venezuela Venezuela Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south... |
1922 |
| Germany | 1923 |
| Czechoslovakia Czechoslovakia Czechoslovakia or Czecho-Slovakia was a sovereign state in Central Europe which existed from October 1918, when it declared its independence from the Austro-Hungarian Empire, until 1992... |
1923 |
| China | 1923 |
| Australia | 1923 |
| Brazil | 1923 |
| Belgium | 1923 |
| Denmark | 1923 |
| Finland | 1923 |
| Italy | 1923 |
| Netherlands East Indies | 1923 |
| South Africa South Africa The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans... |
1923 |
| Spain | 1923 |
| Sweden | 1923 |
| Austria | 1923 |
| Colombia Colombia Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the... |
1929 |
| Costa Rica Costa Rica Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east.... |
1924 |
| Estonia Estonia Estonia , officially the Republic of Estonia , is a state in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by Lake Peipsi and the Russian Federation . Across the Baltic Sea lies... |
1924 |
| Lithuania Lithuania Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark... |
1924 |
| Luxembourg Luxembourg Luxembourg , officially the Grand Duchy of Luxembourg , is a landlocked country in western Europe, bordered by Belgium, France, and Germany. It has two principal regions: the Oesling in the North as part of the Ardennes massif, and the Gutland in the south... |
1924 |
| Newfoundland Newfoundland and Labrador Newfoundland and Labrador is the easternmost province of Canada. Situated in the country's Atlantic region, it incorporates the island of Newfoundland and mainland Labrador with a combined area of . As of April 2011, the province's estimated population is 508,400... |
1924 |
| Serbia Serbia Serbia , officially the Republic of Serbia , is a landlocked country located at the crossroads of Central and Southeast Europe, covering the southern part of the Carpathian basin and the central part of the Balkans... |
1924 |
| Poland | 1924 |
| Norway | 1924 |
| Afghanistan Afghanistan Afghanistan , officially the Islamic Republic of Afghanistan, is a landlocked country located in the centre of Asia, forming South Asia, Central Asia and the Middle East. With a population of about 29 million, it has an area of , making it the 42nd most populous and 41st largest nation in the world... |
1925 |
| Egypt Egypt Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world... |
1925 |
| Japan | 1925 |
| Fiji Fiji Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island... |
1925 |
| Latvia Latvia Latvia , officially the Republic of Latvia , is a country in the Baltic region of Northern Europe. It is bordered to the north by Estonia , to the south by Lithuania , to the east by the Russian Federation , to the southeast by Belarus and shares maritime borders to the west with Sweden... |
1925 |
| Peru Peru Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean.... |
1925 |
| Portugal | 1925 |
| Romania | 1925 |
| Hungary | 1925 |
| Ireland | 1925 |
| Netherlands Antilles Netherlands Antilles The Netherlands Antilles , also referred to informally as the Dutch Antilles, was an autonomous Caribbean country within the Kingdom of the Netherlands, consisting of two groups of islands in the Lesser Antilles: Aruba, Bonaire and Curaçao , in Leeward Antilles just off the Venezuelan coast; and Sint... |
1925 |
| Croatia | 1926 |
| British Guiana British Guiana British Guiana was the name of the British colony on the northern coast of South America, now the independent nation of Guyana.The area was originally settled by the Dutch at the start of the 17th century as the colonies of Essequibo, Demerara, and Berbice... |
1926 |
| Free City of Danzig Free City of Danzig The Free City of Danzig was a semi-autonomous city-state that existed between 1920 and 1939, consisting of the Baltic Sea port of Danzig and surrounding areas.... |
1926 |
| Dominican Republic Dominican Republic The Dominican Republic is a nation on the island of La Hispaniola, part of the Greater Antilles archipelago in the Caribbean region. The western third of the island is occupied by the nation of Haiti, making Hispaniola one of two Caribbean islands that are shared by two countries... |
1926 |
| El Salvador El Salvador El Salvador or simply Salvador is the smallest and the most densely populated country in Central America. The country's capital city and largest city is San Salvador; Santa Ana and San Miguel are also important cultural and commercial centers in the country and in all of Central America... |
1926 |
| Greece | 1926 |
| Guatemala Guatemala Guatemala is a country in Central America bordered by Mexico to the north and west, the Pacific Ocean to the southwest, Belize to the northeast, the Caribbean to the east, and Honduras and El Salvador to the southeast... |
1926 |
| Lithuania Lithuania Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark... |
1926 |
| Algeria Algeria Algeria , officially the People's Democratic Republic of Algeria , also formally referred to as the Democratic and Popular Republic of Algeria, is a country in the Maghreb region of Northwest Africa with Algiers as its capital.In terms of land area, it is the largest country in Africa and the Arab... |
1927 |
| Basutoland Basutoland Basutoland or officially the Territory of Basutoland, was a British Crown colony established in 1884 after the Cape Colony's inability to control the territory... |
1927 |
| Belgian Congo Belgian Congo The Belgian Congo was the formal title of present-day Democratic Republic of the Congo between King Leopold II's formal relinquishment of his personal control over the state to Belgium on 15 November 1908, and Congolese independence on 30 June 1960.-Congo Free State, 1884–1908:Until the latter... |
1927 |
| Bolivia Bolivia Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America... |
1927 |
| Dutch New Guinea | 1927 |
| Greenland Greenland Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for... |
1927 |
| Haiti Haiti Haiti , officially the Republic of Haiti , is a Caribbean country. It occupies the western, smaller portion of the island of Hispaniola, in the Greater Antillean archipelago, which it shares with the Dominican Republic. Ayiti was the indigenous Taíno or Amerindian name for the island... |
1927 |
| India | 1927 |
| Kenya Kenya Kenya , officially known as the Republic of Kenya, is a country in East Africa that lies on the equator, with the Indian Ocean to its south-east... |
1927 |
| Liberia Liberia Liberia , officially the Republic of Liberia, is a country in West Africa. It is bordered by Sierra Leone on the west, Guinea on the north and Côte d'Ivoire on the east. Liberia's coastline is composed of mostly mangrove forests while the more sparsely populated inland consists of forests that open... |
1927 |
| Mauritius Mauritius Mauritius , officially the Republic of Mauritius is an island nation off the southeast coast of the African continent in the southwest Indian Ocean, about east of Madagascar... |
1927 |
| St. Helena | 1927 |
| Siam Thailand Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the... |
1927 |
| Singapore Singapore Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the... |
1927 |
| Suriname Suriname Suriname , officially the Republic of Suriname , is a country in northern South America. It borders French Guiana to the east, Guyana to the west, Brazil to the south, and on the north by the Atlantic Ocean. Suriname was a former colony of the British and of the Dutch, and was previously known as... |
1927 |
| Turkey Turkey Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe... |
1927 |
| French Indochina French Indochina French Indochina was part of the French colonial empire in southeast Asia. A federation of the three Vietnamese regions, Tonkin , Annam , and Cochinchina , as well as Cambodia, was formed in 1887.... |
1927 |
| Honduras Honduras Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize... |
1928 |
| Hong Kong Hong Kong Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour... |
1928 |
| Morocco Morocco Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara... |
1928 |
| Western Samoa | 1928 |
| Bulgaria Bulgaria Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east... |
1929 |
| Falkland Islands Falkland Islands The Falkland Islands are an archipelago in the South Atlantic Ocean, located about from the coast of mainland South America. The archipelago consists of East Falkland, West Falkland and 776 lesser islands. The capital, Stanley, is on East Falkland... |
1929 |
| Mozambique Mozambique Mozambique, officially the Republic of Mozambique , is a country in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi and Zambia to the northwest, Zimbabwe to the west and Swaziland and South Africa to the southwest... |
1929 |
| North Yemen North Yemen North Yemen is a term currently used to designate the Yemen Arab Republic , its predecessor, the Mutawakkilite Kingdom of Yemen , and their predecessors that exercised sovereignty over the territory that is now the north-western part of the state of Yemen in southern Arabia.Neither state ever... |
1929 |
| British Honduras British Honduras British Honduras was a British colony that is now the independent nation of Belize.First colonised by Spaniards in the 17th century, the territory on the east coast of Central America, south of Mexico, became a British crown colony from 1862 until 1964, when it became self-governing. Belize became... |
1930s |
| Bermuda Bermuda Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida... |
1930 |
| Iceland Iceland Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population... |
1930 |
| Israel Israel The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea... |
1930 |
| Tunisia Tunisia Tunisia , officially the Tunisian RepublicThe long name of Tunisia in other languages used in the country is: , is the northernmost country in Africa. It is a Maghreb country and is bordered by Algeria to the west, Libya to the southeast, and the Mediterranean Sea to the north and east. Its area... |
1930 |
| Vatican City Vatican City Vatican City , or Vatican City State, in Italian officially Stato della Città del Vaticano , which translates literally as State of the City of the Vatican, is a landlocked sovereign city-state whose territory consists of a walled enclave within the city of Rome, Italy. It has an area of... |
1931 |
| Ethiopia Ethiopia Ethiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2... |
1931 |
| Madagascar Madagascar The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa... |
1931 |
| Nicaragua Nicaragua Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean... |
1931 |
| Nigeria Nigeria Nigeria , officially the Federal Republic of Nigeria, is a federal constitutional republic comprising 36 states and its Federal Capital Territory, Abuja. The country is located in West Africa and shares land borders with the Republic of Benin in the west, Chad and Cameroon in the east, and Niger in... |
1931 |
| Ecuador Ecuador Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border... |
1931 |
| British Leeward Islands British Leeward Islands The British Leeward Islands was a British colony existing between 1833 and 1960, and consisting of Antigua, Barbuda, the British Virgin Islands, Montserrat, Saint Kitts, Nevis, Anguilla and Dominica.... |
1932 |
| French West Africa French West Africa French West Africa was a federation of eight French colonial territories in Africa: Mauritania, Senegal, French Sudan , French Guinea , Côte d'Ivoire , Upper Volta , Dahomey and Niger... |
1932 |
| Macau Macau Macau , also spelled Macao , is, along with Hong Kong, one of the two special administrative regions of the People's Republic of China... |
1932 |
| Saudi Arabia Saudi Arabia The Kingdom of Saudi Arabia , commonly known in British English as Saudi Arabia and in Arabic as as-Sa‘ūdiyyah , is the largest state in Western Asia by land area, constituting the bulk of the Arabian Peninsula, and the second-largest in the Arab World... |
1932 |
| Southern Rhodesia Southern Rhodesia Southern Rhodesia was the name of the British colony situated north of the Limpopo River and the Union of South Africa. From its independence in 1965 until its extinction in 1980, it was known as Rhodesia... |
1932 |
| British Windward Islands British Windward Islands The British Windward Islands was a British colony existing between 1833 and 1960 and consisting of the islands of Grenada, St Lucia, Saint Vincent, the Grenadines, Barbados , Tobago , and Dominica, previously included in the... |
1934 |
| Mongolia Mongolia Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest... |
1934 |
| Papua New Guinea Papua New Guinea Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands... |
1934 |
| Sierra Leone Sierra Leone Sierra Leone , officially the Republic of Sierra Leone, is a country in West Africa. It is bordered by Guinea to the north and east, Liberia to the southeast, and the Atlantic Ocean to the west and southwest. Sierra Leone covers a total area of and has an estimated population between 5.4 and 6.4... |
1934 |
| Andorra Andorra Andorra , officially the Principality of Andorra , also called the Principality of the Valleys of Andorra, , is a small landlocked country in southwestern Europe, located in the eastern Pyrenees mountains and bordered by Spain and France. It is the sixth smallest nation in Europe having an area of... |
1935 |
| Gold Coast Gold Coast (British colony) The Gold Coast was a British colony on the Gulf of Guinea in west Africa that became the independent nation of Ghana in 1957.-Overview:The first Europeans to arrive at the coast were the Portuguese in 1471. They encountered a variety of African kingdoms, some of which controlled substantial... |
1935 |
| Malta Malta Malta , officially known as the Republic of Malta , is a Southern European country consisting of an archipelago situated in the centre of the Mediterranean, south of Sicily, east of Tunisia and north of Libya, with Gibraltar to the west and Alexandria to the east.Malta covers just over in... |
1935 |
| Paraguay Paraguay Paraguay , officially the Republic of Paraguay , is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. Paraguay lies on both banks of the Paraguay River, which runs through the center of the... |
1936 |
| Bahamas | 1936 |
| Iraq Iraq Iraq ; officially the Republic of Iraq is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert.... |
1936 |
| Gilbert and Ellice Islands Gilbert and Ellice Islands The Gilbert and Ellice Islands were a British protectorate from 1892 and colony from 1916 until 1 January 1976, when the islands were divided into two different colonies which became independent nations shortly after... |
1937 |
| Lebanon Lebanon Lebanon , officially the Republic of LebanonRepublic of Lebanon is the most common term used by Lebanese government agencies. The term Lebanese Republic, a literal translation of the official Arabic and French names that is not used in today's world. Arabic is the most common language spoken among... |
1937 |
| Albania Albania Albania , officially known as the Republic of Albania , is a country in Southeastern Europe, in the Balkans region. It is bordered by Montenegro to the northwest, Kosovo to the northeast, the Republic of Macedonia to the east and Greece to the south and southeast. It has a coast on the Adriatic Sea... |
1938 |
| Cyprus Cyprus Cyprus , officially the Republic of Cyprus , is a Eurasian island country, member of the European Union, in the Eastern Mediterranean, east of Greece, south of Turkey, west of Syria and north of Egypt. It is the third largest island in the Mediterranean Sea.The earliest known human activity on the... |
1938 |
| Jamaica Jamaica Jamaica is an island nation of the Greater Antilles, in length, up to in width and 10,990 square kilometres in area. It is situated in the Caribbean Sea, about south of Cuba, and west of Hispaniola, the island harbouring the nation-states Haiti and the Dominican Republic... |
1938 |
| Pitcairn Islands Pitcairn Islands The Pitcairn Islands , officially named the Pitcairn, Henderson, Ducie and Oeno Islands, form a group of four volcanic islands in the southern Pacific Ocean. The islands are a British Overseas Territory and overseas territory of the European Union in the Pacific... |
1938 |
| Trinidad and Tobago Trinidad and Tobago Trinidad and Tobago officially the Republic of Trinidad and Tobago is an archipelagic state in the southern Caribbean, lying just off the coast of northeastern Venezuela and south of Grenada in the Lesser Antilles... |
1938 |
| French Equatorial Africa French Equatorial Africa French Equatorial Africa or the AEF was the federation of French colonial possessions in Middle Africa, extending northwards from the Congo River to the Sahara Desert.-History:... |
1939 |
| Libya Libya Libya is an African country in the Maghreb region of North Africa bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad and Niger to the south, and Algeria and Tunisia to the west.... |
1939 |
| Aden Aden Aden is a seaport city in Yemen, located by the eastern approach to the Red Sea , some 170 kilometres east of Bab-el-Mandeb. Its population is approximately 800,000. Aden's ancient, natural harbour lies in the crater of an extinct volcano which now forms a peninsula, joined to the mainland by a... |
1940 |
| Bechuanaland | 1940 |
| British Somaliland British Somaliland British Somaliland was a British protectorate in the northern part of present-day Somalia. For much of its existence, British Somaliland was bordered by French Somaliland, Ethiopia, and Italian Somaliland. From 1940 to 1941, it was occupied by the Italians and was part of Italian East Africa... |
1940 |
| Iran Iran Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia... |
1940 |
| Anglo-Egyptian Sudan Anglo-Egyptian Sudan Anglo-Egyptian Sudan referred to the manner by which Sudan was administered between 1899 and 1956, when it was a condominium of Egypt and the United Kingdom.-Union with Egypt:... |
1940 |
| Bahrain Bahrain ' , officially the Kingdom of Bahrain , is a small island state near the western shores of the Persian Gulf. It is ruled by the Al Khalifa royal family. The population in 2010 stood at 1,214,705, including 235,108 non-nationals. Formerly an emirate, Bahrain was declared a kingdom in 2002.Bahrain is... |
1941 |
| Northern Rhodesia Northern Rhodesia Northern Rhodesia was a territory in south central Africa, formed in 1911. It became independent in 1964 as Zambia.It was initially administered under charter by the British South Africa Company and formed by it in 1911 by amalgamating North-Western Rhodesia and North-Eastern Rhodesia... |
1941 |
| Seychelles Seychelles Seychelles , officially the Republic of Seychelles , is an island country spanning an archipelago of 115 islands in the Indian Ocean, some east of mainland Africa, northeast of the island of Madagascar.... |
1945 |
| Syria Syria Syria , officially the Syrian Arab Republic , is a country in Western Asia, bordering Lebanon and the Mediterranean Sea to the West, Turkey to the north, Iraq to the east, Jordan to the south, and Israel to the southwest.... |
1945 |
| Brunei Brunei Brunei , officially the State of Brunei Darussalam or the Nation of Brunei, the Abode of Peace , is a sovereign state located on the north coast of the island of Borneo, in Southeast Asia... |
1947 |
| Spanish Guinea Spanish Guinea Spanish Guinea was an African colony of Spain that became the independent nation of Equatorial Guinea.-History:The Portuguese explorer, Fernão do Pó, seeking a route to India, is credited with having discovered the island of Bioko in 1472. He called it Formosa , but it quickly took on the name of... |
1947 |
| Transjordan Transjordan The Emirate of Transjordan was a former Ottoman territory in the Southern Levant that was part of the British Mandate of Palestine... |
1948 |
| Nepal Nepal Nepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India... |
1950 |
| Sao Tome and Principe São Tomé and Príncipe São Tomé and Príncipe, officially the Democratic Republic of São Tomé and Príncipe, is a Portuguese-speaking island nation in the Gulf of Guinea, off the western equatorial coast of Central Africa. It consists of two islands: São Tomé and Príncipe, located about apart and about , respectively, off... |
1950 |
| Cape Verde Islands | 1951 |
| Kuwait Kuwait The State of Kuwait is a sovereign Arab state situated in the north-east of the Arabian Peninsula in Western Asia. It is bordered by Saudi Arabia to the south at Khafji, and Iraq to the north at Basra. It lies on the north-western shore of the Persian Gulf. The name Kuwait is derived from the... |
1951 |
| Tanganyika Tanganyika Tanganyika , later formally the Republic of Tanganyika, was a sovereign state in East Africa from 1961 to 1964. It was situated between the Indian Ocean and the African Great Lakes of Lake Victoria, Lake Malawi and Lake Tanganyika... |
1951 |
| Portuguese Timor Portuguese Timor Portuguese Timor was the name of East Timor when it was under Portuguese control. During this period, Portugal shared the island of Timor with the Netherlands East Indies, and later with Indonesia.... |
1960 |
| Maldives Maldives The Maldives , , officially Republic of Maldives , also referred to as the Maldive Islands, is an island nation in the Indian Ocean formed by a double chain of twenty-six atolls oriented north-south off India's Lakshadweep islands, between Minicoy Island and... |
1962 |
| Nauru Nauru Nauru , officially the Republic of Nauru and formerly known as Pleasant Island, is an island country in Micronesia in the South Pacific. Its nearest neighbour is Banaba Island in Kiribati, to the east. Nauru is the world's smallest republic, covering just... |
1968 |
| Qatar Qatar Qatar , also known as the State of Qatar or locally Dawlat Qaṭar, is a sovereign Arab state, located in the Middle East, occupying the small Qatar Peninsula on the northeasterly coast of the much larger Arabian Peninsula. Its sole land border is with Saudi Arabia to the south, with the rest of its... |
1968 |
| South West Africa South West Africa South-West Africa was the name that was used for the modern day Republic of Namibia during the earlier eras when the territory was controlled by the German Empire and later by South Africa.... |
1969 |
| Oman Oman Oman , officially called the Sultanate of Oman , is an Arab state in southwest Asia on the southeast coast of the Arabian Peninsula. It is bordered by the United Arab Emirates to the northwest, Saudi Arabia to the west, and Yemen to the southwest. The coast is formed by the Arabian Sea on the... |
1970 |
| Bhutan Bhutan Bhutan , officially the Kingdom of Bhutan, is a landlocked state in South Asia, located at the eastern end of the Himalayas and bordered to the south, east and west by the Republic of India and to the north by the People's Republic of China... |
1973 |
Notes:
: Date unconfirmed.
: Broadcasts had also been available from Louisiana and Alabama since 1922.
: Broadcasts were also available from North Carolina and Georgia.
: Broadcasts were also available from Colorado since 1921.
: Radio broadcasting in Java briefly ceased after a station was destroyed by lightning.
: Broadcasts from Argentina had also been available as is the case today.
: Radio broadcasting had also been received from Italy, since Vatican City lies within the vicinity of Rome as is the case today.
: Malta had also received radio broadcasts from Italy. The British adopted a radio service on the island to counter Fascist propaganda.
: Radio broadcasts did exist in the Bahamas prior to 1936. Before then, they were received from the United States.
: Also received radio broadcasts from nearby Yugoslavia.
: Broadcasting in Aden ceased in 1946-1947 and again from 1948-1955.
: Andorra also received radio broadcasts from Spain.
: Radio broadcasts from the Trust Territory of the Pacific Islands had also been available.
: Broadcasts had also been received from Saudi Arabia and Bahrain.
: Broadcasts had previously been received from South Africa.
FM and television start
In 1933, FM radio was patented by inventor Edwin H. ArmstrongEdwin Armstrong
Edwin Howard Armstrong was an American electrical engineer and inventor. Armstrong was the inventor of modern frequency modulation radio....
. FM uses frequency modulation
Frequency modulation
In telecommunications and signal processing, frequency modulation conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant...
of the radio wave to minimize static
White noise
White noise is a random signal with a flat power spectral density. In other words, the signal contains equal power within a fixed bandwidth at any center frequency...
and interference from electrical equipment and the atmosphere, in the audio program. In 1937, W1XOJ, the first experimental FM radio station, was granted a construction permit by the U.S. Federal Communications Commission
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...
(FCC). In the 1930s, standard analog television
Analog television
Analog television is the analog transmission that involves the broadcasting of encoded analog audio and analog video signal: one in which the message conveyed by the broadcast signal is a function of deliberate variations in the amplitude and/or frequency of the signal...
transmissions started in Europe, and then in the 1940s in North America. Armstrong's FM system was designated by the FCC to transmit and receive television sound.
FM in Europe
After World War II, the FM radio broadcast was introduced in Germany. In 1948, a new wavelength plan was set up for Europe at a meeting in CopenhagenCopenhagen
Copenhagen is the capital and largest city of Denmark, with an urban population of 1,199,224 and a metropolitan population of 1,930,260 . With the completion of the transnational Øresund Bridge in 2000, Copenhagen has become the centre of the increasingly integrating Øresund Region...
. Because of the recent war, Germany (which did not exist as a state and so was not invited) was only given a small number of medium-wave
Mediumwave
Medium wave is the part of the medium frequency radio band used mainly for AM radio broadcasting. For Europe the MW band ranges from 526.5 kHz to 1606.5 kHz...
frequencies, which are not very good for broadcasting. For this reason Germany began broadcasting on UKW ("Ultrakurzwelle", i.e. ultra short wave, nowadays called VHF
Very high frequency
Very high frequency is the radio frequency range from 30 MHz to 300 MHz. Frequencies immediately below VHF are denoted High frequency , and the next higher frequencies are known as Ultra high frequency...
) which was not covered by the Copenhagen plan. After some amplitude modulation
Amplitude modulation
Amplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
experience with VHF, it was realized that FM radio was a much better alternative for VHF radio than AM. Because of this history FM Radio is still referred to as "UKW Radio" in Germany. Other European nations followed a bit later, when the superior sound quality of FM and the ability to run many more local stations because of the more limited range of VHF broadcasts were realized.
Later 20th century developments
In 1954 Regency introduced a pocket transistorTransistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...
radio, the TR-1
Regency TR-1
The Regency TR-1 was the first commercially sold transistor radio.-History:Two companies working together, Texas Instruments of Dallas, Texas and Industrial Development Engineering Associates of Indianapolis, Indiana, were behind the unveiling of the Regency TR-1, the world's first...
, powered by a "standard 22.5V Battery". In the early 1960s, VOR
VHF omnidirectional range
VOR, short for VHF omnidirectional radio range, is a type of radio navigation system for aircraft. A VOR ground station broadcasts a VHF radio composite signal including the station's identifier, voice , and navigation signal. The identifier is typically a two- or three-letter string in Morse code...
systems finally became widespread for aircraft
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...
navigation; before that, aircraft used commercial AM radio stations for navigation. (AM stations are still marked on U.S. aviation
Aviation
Aviation is the design, development, production, operation, and use of aircraft, especially heavier-than-air aircraft. Aviation is derived from avis, the Latin word for bird.-History:...
charts). In 1960 Sony
Sony
, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
introduced their first transistorized radio, small enough to fit in a vest pocket, and able to be powered by a small battery. It was durable, because there were no tubes to burn out. Over the next twenty years, transistors displaced tubes almost completely except for picture tubes
Cathode ray tube
The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...
and very high power or very high frequency uses.
Color television and digital
- 1963: Color television was commercially transmitted, and the first (radio) communication satellite, TelstarTelstarTelstar is the name of various communications satellites, including the first such satellite to relay television signals.The first two Telstar satellites were experimental and nearly identical. Telstar 1 was launched on top of a Thor-Delta rocket on July 10, 1962...
, was launched. - Late 1960s: The USA long-distance telephone network began to convert to a digital network, employing digital radioDigital radioDigital radio has several meanings:1. Today the most common meaning is digital radio broadcasting technologies, such as the digital audio broadcasting system, also known as Eureka 147. In these systems, the analog audio signal is digitized into zeros and ones, compressed using formats such as...
s for many of its links. - 1970s: LORANLORANLORAN is a terrestrial radio navigation system using low frequency radio transmitters in multiple deployment to determine the location and speed of the receiver....
became the premier radio navigation system. Soon, the U.S. Navy experimented with satellite navigation. - 1987: The GPSGlobal Positioning SystemThe Global Positioning System is a space-based global navigation satellite system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight to four or more GPS satellites...
constellation of satellites was launched. - Early 1990s: amateur radioAmateur radioAmateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...
experimenters began to use personal computers with audio cards to process radio signals. - 1994: The U.S. Army and DARPA launched an aggressive successful project to construct a software radio that could become a different radio on the fly by changing software.
- Late 1990s: Digital transmissions began to be applied to broadcastingBroadcastingBroadcasting is the distribution of audio and video content to a dispersed audience via any audio visual medium. Receiving parties may include the general public or a relatively large subset of thereof...
.
Telex on radio
TelegraphyTelegraphy
Telegraphy is the long-distance transmission of messages via some form of signalling technology. Telegraphy requires messages to be converted to a code which is known to both sender and receiver...
did not go away on radio. Instead, the degree of automation increased. On land-lines in the 1930s, Teletypewriters automated encoding, and were adapted to pulse-code dialing to automate routing, a service called telex
Teleprinter
A teleprinter is a electromechanical typewriter that can be used to communicate typed messages from point to point and point to multipoint over a variety of communication channels that range from a simple electrical connection, such as a pair of wires, to the use of radio and microwave as the...
. For thirty years, telex was the absolute cheapest form of long-distance communication, because up to 25 telex channels could occupy the same bandwidth as one voice channel. For business and government, it was an advantage that telex directly produced written documents.
Telex systems were adapted to short-wave radio by sending tones over single sideband. CCITT
ITU-T
The ITU Telecommunication Standardization Sector is one of the three sectors of the International Telecommunication Union ; it coordinates standards for telecommunications....
R.44 (the most advanced pure-telex standard) incorporated character-level error detection and retransmission as well as automated encoding and routing. For many years, telex-on-radio (TOR) was the only reliable way to reach some third-world countries. TOR remains reliable, though less-expensive forms of e-mail are displacing it. Many national telecom companies historically ran nearly pure telex networks for their governments, and they ran many of these links over short wave radio.
Legal issues with radio
When radio was first introduced in the 1930s many predicted the end of records. Radio was a free medium for the public to hear music for which they would normally pay. While some companies saw radio as a new avenue for promotion, others feared it would cut into profits from record sales and live performances. Many companies had their major stars sign agreements that they would not appear on radio.Indeed, the music recording industry had a severe drop in profits after the introduction of the radio. For a while, it appeared as though radio was a definite threat to the record industry. Radio ownership grew from 2 out of 5 homes in 1931 to 4 out of 5 homes in 1938. Meanwhile record sales fell from $75 million in 1929 to $26 million in 1938 (with a low point of $5 million in 1933), though the economics of the situation were also affected by the Great Depression.
The copyright owners of these songs were concerned that they would see no gain from the popularity of radio and the ‘free’ music it provided. Luckily, everything they needed to make this new medium work for them already existed in previous copyright law. The copyright holder for a song had control over all public performances ‘for profit.’ The problem now was proving that the radio industry, which was just figuring out for itself how to make money from advertising and currently offered free music to anyone with a receiver, was making a profit from the songs.
The test case was against Bamberger Department Store in Newark, New Jersey in 1922. The store was broadcasting music throughout its store on the radio station WOR. No advertisements were heard, except for at the beginning of the broadcast which announced "L. Bamberger and Co., One of America's Great Stores, Newark, New Jersey." It was determined through this and previous cases (such as the lawsuit against Shanley's Restaurant) that Bamberger was using the songs for commercial gain, thus making it a public performance for profit, which meant the copyright owners were due payment.
With this ruling the American Society of Composers, Authors and Publishers (ASCAP) began collecting licensing fees from radio stations in 1923. The beginning sum was $230 for all music protected under ASCAP, but for larger stations the price soon ballooned up to $5,000. Edward Samuel's reports in his book The Illustrated Story of Copyright that "radio and TV licensing represents the single greatest source of revenue for ASCAP and its composers […] and average member of ASCAP gets about $150–$200 per work per year, or about $5,000-$6,000 for all of a member's compositions. Not long after the Bamberger ruling, ASCAP had to once again defend their right to charge fees in 1924. The Dill Radio Bill would have allowed radio stations to play music without paying and licensing fees to ASCAP or any other music-licensing corporations. The bill did not pass.
Exotic technologies
- Meteor scatter
- Earth-Moon-Earth communicationEME (communications)Earth-Moon-Earth, also known as moon bounce, is a radio communications technique which relies on the propagation of radio waves from an Earth-based transmitter directed via reflection from the surface of the Moon back to an Earth-based receiver....
See also
| Radio Pioneers |
|---|
scientists and inventors |
Many contributed to wireless. Individuals that helped to further the science include, among others:
---- See also: :Category:Radio pioneers :Category:Radio people :Category:History of radio |
General
- Amateur radio historyAmateur radio historyThroughout the history of amateur radio, amateur radio enthusiasts have made significant contributions to science, engineering, industry, and social services. Research by amateur radio operators has founded new industries, built economies, empowered nations, and saved lives in times of...
- Birth of public radio broadcastingBirth of public radio broadcastingBirth of public radio broadcasting is credited to Lee de Forest. A 1907 Lee De Forest company advertisement said, -Date:On January 13, 1910, the first public radio broadcast was an experimental transmission of a live Metropolitan Opera House performance of several famous opera...
- Digital audio broadcastingDigital audio broadcastingDigital Audio Broadcasting is a digital radio technology for broadcasting radio stations, used in several countries, particularly in Europe. As of 2006, approximately 1,000 stations worldwide broadcast in the DAB format....
(DAB) - Digital Radio MondialeDigital Radio MondialeDigital Radio Mondiale is a set of digital audio broadcasting technologies designed to work over the bands currently used for AM broadcasting, particularly shortwave...
- History of science and technologyHistory of science and technologyThe history of science and technology is a field of history which examines how humanity's understanding of the natural world and ability to manipulate it have changed over the centuries...
- History of televisionHistory of televisionThe history of television records the work of numerous engineers and inventors in several countries over many decades. The fundamental principles of television were initially explored using electromechanical methods to scan, transmit and reproduce an image...
- Internet radioInternet radioInternet radio is an audio service transmitted via the Internet...
- List of old-time radio people
- Personal area networkPersonal area networkA personal area network is a computer network used for communication among computer devices, including telephones and personal digital assistants, in proximity to an individual's body. The devices may or may not belong to the person in question. The reach of a PAN is typically a few meters...
s - Radio Act of 1912Radio Act of 1912The Radio Act of 1912 is a United States federal law that mandated that all radio stations in the US be licensed by the federal government, as well as mandating that seagoing vessels continuously monitor distress frequencies....
- Radio Act of 1927
- Sirius Satellite RadioSirius Satellite RadioSirius Satellite Radio is a satellite radio service operating in North America, owned by Sirius XM Radio.Headquartered in New York City, with smaller studios in Los Angeles and Memphis, Sirius was officially launched on July 1, 2002 and currently provides 69 streams of music and 65 streams of...
- Spark gap transmitter
- Timeline of radioTimeline of radioThe timeline of radio lists within the history of radio, the technology and events that produced instruments that use radio waves and activities that people undertook...
- WirelessWirelessWireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications...
- Wireless LANWireless LANA wireless local area network links two or more devices using some wireless distribution method , and usually providing a connection through an access point to the wider internet. This gives users the mobility to move around within a local coverage area and still be connected to the network...
s - Wireless Ship Act of 1910Wireless Ship Act of 1910The Wireless Ship Act was passed by the United States Congress in 1910, requiring all ships of the United States traveling over two-hundred miles off the coast and carrying over fifty passengers to be equipped with wireless radio equipment with a range of one-hundred miles...
- XM Radio
Media and documentaries
- Empire of the Air: The Men Who Made RadioEmpire of the Air: The Men Who Made RadioEmpire of the Air: The Men Who Made Radio is a non-fiction book by Tom Lewis, a history of radio in the United States, published by HarperCollins in 1991. The book was adapted into both a 1992 documentary film by Ken Burns and a 1992 radio drama written and directed by David Ossman...
(1992) by Ken BurnsKen BurnsKenneth Lauren "Ken" Burns is an American director and producer of documentary films, known for his style of using archival footage and photographs...
, PBS documentary based on the 1991 book, Empire of the Air: The Men Who Made Radio by Tom Lewis, 1st ed., New York : E. Burlingame Books, ISBN 0-06-018215-6
External links
- "A Comparison of the Tesla and Marconi Low-Frequency Wireless Systems ". Twenty First Century Books, Breckenridge, Co.
- Marconi's Early Wireless Experiments, 1895 IEEE History Center
- Sparks Telegraph Key Review
- Early Radio History
- Radio waves, the Hertzian Radiation: what it is and how it happens.
- Information on the development of Radio at Camp Evans, New Jersey
- "The Invention of Radio". inventors.about.com.
- Zenonas Langaitis — Old radios from Lithuania * (Europa, Baltic States, past USSR
- "The Invention of the Radio". Through the wires, a century of communication, library.thinkquest.org.
- "Presentation of the Edison Medal to Nikola Tesla". Minutes of the Annual Meeting of the American Institute of Electrical Engineers. Held at the Engineering Society Building, New York City, Friday evening, May 18, 1917.
- "Guglielmo Marconi and Early Systems of Wireless Communication". Marconi.com. (PDF file)
- Timeline of the First Thirty Years of Radio 1895 – 1925; An important chapter in the Death of Distance. Nova Scotia, Canada, March 14, 2006.
- Ontario Plaques - The Rogers Batteryless Radio
- Brazilian experimenter Roberto Landell de Moura
- Portuguese Radio History: Telefonia Sem Fios - História da Rádio em Portugal
- Cybertelecom :: Radio History (legal and regulatory)
- Canadian Broadcasting Corporation archives