History of Radio 1

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History of radio

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For the controversy about who invented radio, seeInvention of radio. For theprogramming of early radio stations, see Old-time radio.

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The early history of radio is the history oftechnology that produced radio instruments

that use radio waves. Within the timeline of radio, many people contributed theory and

inventions in what became radio.[1]

Radio development began as "wireless

telegraphy".[1]

Later radio history increasingly involves matters of programming and

content.

Who invented the radio?

In the history of radio anddevelopment of "wireless

telegraphy", several people areclaimed to have "invented the

radio" leading to a great radiocontroversy. The most commonly

accepted claims are:

y Jagadish Chandra Bosey Guglielmo Marconi, who

equipped ships with life-

saving wireless

communications,

conducted a reported

transatlantic radio

communications

experiments in 1901 and

established the first

commercial transatlantic

radio service in 1907.y Alexander Stepanovich

Popov

y Nikola Tesla, whodeveloped means to

produce radio frequencycurrents, publicly

demonstrated theprinciples of radio, and


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o 3.4 Ferdinand Brauno 3.5 Charles David Herroldo 3.6 Harold J. Powero 3.7 Edwin Armstrong

y 4 Otherinnovatorsy 5 Audio broadcasting (1919 to 1950s)

o 5.1 Crystal setso 5.2 The first vacuum tubeso 5.3 Licensed commercial public radio stationso 5.4 Dates of first radio stations

5.4.1 US and Canadian territories 5.4.2Other countries

o 5.5 FM and television starto 5.6 Marconi/Tesla priority disputeo 5.7 FMin Europe

y 6 Later20th century developmentso 6.1 Colortelevision and digitalo 6.2 Telex on radio

y 7 21st century developmento 7.1 Internet radioo 7.2Digital audio broadcastingo 7.3 Related articles

y 8 Legalissues with radioy 9 Exotic technologiesy 10 See alsoy 11 otes and citationsy 12 Footnotesy 13 References

o 13.1 Primary sourceso 13.2 Secondary sources

y 14 Media and documentariesy 15 Externallinks

Wi eless experi ents of the 19th century

In the late 19th century it was clearto various scientists and experimenters that wireless

communication was possible. Various theoretical and experimentalinnovations led to

the development of radio and the communication system we know today. Some early

work was done by local effects and experiments ofelectromagnetic induction. Manyunderstood thatthere was nothing similarto the "etherealtelegraphy"

[2

[3]and

telegraphy by induction; the phenomena being wholly distinct. Wireless telegraphy wasbeginning to take hold and the practice oftransmitting messages without wires was

being developed. Many people worked on developing the devices and improvements.

Faraday


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James Clerk Maxwell, a theoretical physicist who developed a set of equationsdescribing electromagnetic waves. These later later became known as Maxwell s

equations.

In 1 31, Michael Faraday began a series of experiments in which he discovered

electromagnetic induction. The relation was mathematically modelled by Faraday s law,

which subsequently became one of the fourMaxwell equations. Faraday proposed thatelectromagnetic forces extended into the empty space around the conductor, but did not

complete his work involving that proposal.

Maxwell

Between 1 61 and 1 65, based on the earlier experimental work of Faraday and other

scientists, James Clerk Maxwell developed his theory of electromagnetism, which

predicted the existence of electromagnetic waves. In 1 73 Maxwell described thetheoretical basis of the propagation of electromagnetic waves in his paper to the Royal

Society, "A Dynamical Theory of the Electromagnetic Field."

William Henry Ward

In April 1 7 William enry Ward received U.S. Patent 1 6,356 for radio

development. owever, this patent did not refer to any known scientific theory ofelectromagnetism and could never have received and transmitted radio waves.

Mahlon Loomis

A few months after Ward received his patent, Mahlon Loomis ofWest irginia

received U.S. Patent 1 9,971 for a "wireless telegraph" in July 1 7 . This claimed to

utili e atmospheric electricity to eliminate the overhead wire used by the existing

telegraph systems. It did not contain diagrams or specific methods and it did not refer toor incorporate any known scientific theory. It is substantially similar toWilliam enry

Ward s patent and could not have transmitted and received radio waves.

Edison (1875)


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Towards the end of 1875, while experimenting with the telegraph, Thomas Edison

noted a phenomenon that he termed "etheric force", announcing itto the press onovember28. He abandoned this research when Elihu Thomson, among others,

ridiculed the idea. The idea was not based on the electromagnetic waves described byMaxwell.

David E. Hughes

In 1878, David E. Hughes noticed that sparks could be heard in a telephone receiver

when experimenting with his carbon microphone. He developed this carbon-based

detector further and eventually could detect signals over a few hundred yards. He

demonstrated his discovery to the Royal Society in 1880, but was told it was merelyinduction, and therefore abandoned further research.

Calzecchi-Onesti

In 1884, Temistocle Calzecchi-Onesti atFermoin Italy invented a primitive device thatresponded to radio waves. It consisted of a tube filled with iron filings, called a

"coherer". This device was a critical discovery because it would later be developed tobecome the first practical radio detector.

Edouard Branly

Between 1884 and 1886, Edouard Branly of France produced an improved version of

the coherer.

Edison (1885)

In 1885, Edison took outU.S. Patent 465,971 on a system of radio communication

between ships (which later he sold to Marconi). The patent, however, was not based onthe transmission and reception of electromagnetic waves.

Hertz

Between 1886 and 1888, Heinrich RudolfHertz studied Maxwell's theory and validated

itthrough experiment. He demonstrated the transmission and reception oftheelectromagnetic waves predicted by Maxwell and thus was the first person to

intentionally transmit and receive radio. He discovered thatthe electromagneticequations could be reformulated into apartial differential equation called the wave

equation. Famously, he saw no practical use for his discovery. For more information seeHertz's radio work.

Stubblefield

Claims have been made thatMurray, Kentucky farmer athan Stubblefield developed

radio between 1885 and 1892, before either Tesla orMarconi, but his devices seemed tohave worked by inductiontransmission ratherthan radio transmission.

Landell de Moura


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Between 1 93 and 1 94, Roberto Landell de Moura, a Bra ilian priest and scientist,

conducted experiments in wireless transmissions. e did not publici e his achievement

until 1900, when he held a public demonstration of a wireless transmission of voice in

So Paulo, Bra il on June 3.

Beginnings of radio

Nikola Tesla developed means to reliably produce radio frequencies, publicly

demonstrated the principles of radio, and transmitted long distant signals.

There are varying disputed claims about who invented radio, which in the beginning

was called "wireless telegraphy". The key invention for the beginning of "wireless

transmission of data using the entire frequency spectrum", known as thespark-gaptransmitter, has been attributed to various men. Marconi equipped ships with lifesaving

wireless communications and established the first transatlantic radio service. Tesladeveloped means to reliably produce radio frequency electrical currents, publicly

demonstrated the principles of radio, and transmitted long distance signals.

Nikola Tesla

In 1 91 Tesla began his research into radio. e later published an article, "The TrueWireless", concerning this research.[4] In 1 9 he gave a lecture called "Experiments

with Alternate Currents of igh Potential and igh Frequency", in London (Availableat Project Gutenberg).[5] In 1 93, at St. Louis, Missouri, Tesla gave a public

demonstration of "wireless" radio communication. Addressing theFranklin Institute inPhiladelphia and theNational Electric LightAssociation, he described in detail the

principles of radio communication.[6]

The apparatus that Tesla used contained all the elements that were incorporated intoradio systems before the development of the "oscillation valve", the earlyvacuum tube.


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Tesla initially used sensitive electromagnetic receivers,[7]

that were unlike the less

responsive cohererslater used by Marconi and other early experimenters.

Afterward, the principle of radio communication (sending signals through space toreceivers) was publicized widely from Tesla's experiments and demonstrations. Various

scientists, inventors, and experimenters began to investigate wireless methods. For more

information see Tesla's wireless work.

Oliver Lodge

Oliver Lodgetransmitted radio signals on August 14, 1894 (one year after Tesla, five

years afterHeinrich Hertz and one year before Marconi) at a meeting ofthe British

Association forthe Advancement of Science atOxford University.[8]

(In 1995, the

Royal Society recognized this scientific breakthrough at a special ceremony atOxford

University. For more information, seePast Y ars:

n

ut

i raphy, ew York:

Charles Scribner's Sons, p231.)

On 19 August 1894 Lodge demonstrated the reception ofMorse code signalling via

radio waves using a "coherer". He improved Edouard Branly's coherer radio wave

detector by adding a "trembler" which dislodged clumped filings, thus restoring the

device's sensitivity. [9] In August 1898 he gotU.S. Patent 609,154, "Electric

Telegraphy", that made wireless signals using Ruhmkorff coils orTesla coils forthe

transmitter and a Branly coherer forthe detector. This was key to the "syntonic"tuningconcept. In 1912 Lodge sold the patentto Marconi.

Jagdish Chandra Bose

In ovember 1894, the Indian physicist, Jagdish Chandra Bose, demonstrated publiclythe use of radio waves in Calcutta, but he was notinterested in patenting his work.

[10]

Bose ignited gunpowder and rang a bell at a distance using electromagnetic waves,proving that communication signals can be sent without using wires. He was thus the

firstto send and receive radio waves over a significant distance but did not

commercially exploitthis achievement.

The 1895 public demonstration by Bose in Calcutta was before Marconi's wireless

signalling experiment on Salisbury Plainin England in May 1897.[11][12]

In 1896, the

Daily Chroni l of England reported on his UHF experiments:" he inventor (J.C.

Bose) has transmitted si nals to a distance ofnearly a mile and herein lies thefirstand

obvious and exceedingly valuable application ofthis newtheoreticalmarvel."

Alexander Popov


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Popov was the first man to demonstrate the practical applications of radio waves.

In 1 95, the Russian physicist Alexander Popov built a coherer. n May 7, 1 95, Popov

performed a public demonstration of transmission and reception of radio waves used for

communication at the Russian Physical and Chemical Society, using his coherer:[13]

this

day has since been celebrated in Russia as "Radio ay". e did not apply for a patent

for this invention. Popov s early experiments were transmissions of only 600yards

(550 m). Popov was the first to develop a practical communication system based on the

coherer, and is usually considered by the Russians to have been the inventor of

radio.[14][15]

Around March 1 96 Popov demonstrated in public the transmission of radio waves,

between different campus buildings, to theSaint Petersburg Physical Society. (This was

before the public demonstration of the Marconi system around September 1 96.) Perother accounts, however, Popov achieved these results only in ecember 1 97that is,

after publication of Marconi s patent.[16]

In 1 9 his signal was received 6 miles(9.7 km) away, and in 1 99 30 miles away. In 1900, Popov stated at theCongress of

Russian Electrical Engineers that,

"the emission and reception of signals by Marconi by means of electric

oscillations was nothing new, as inAmericaNikola Tesla did the same

experiments in 1893."[17][1 ]

Later Popov experimented with ship-to-shore communication. Popov died in 1905 and

his claim was not pressed by the Russian government until 1945.

Ernest Rutherford

TheNew ZealanderErnest Rutherford, 1st Baron Rutherford ofNelson was

instrumental in the development of radio. In 1 95 he was awarded anExhibition of1 51 Science Research Scholarship to Cambridge. e arrived in England with a

reputation as an innovator and inventor, and distinguished himself in several fields,

initially by working out the electrical properties of solids and then using wireless waves

as a method of signalling. Rutherford was encouraged in his work bySir Robert Ball,

who had been scientific adviser to the body maintaininglighthouses on the Irish coast;

he wished to solve the difficult problem of a ship s inability to detect a lighthouse in fog.Sensing fame and fortune, Rutherford increased the sensitivity of his apparatus until he

could detect electromagnetic waves over a distance of several hundred meters. The


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commercial development, though, of wireless technology was left for others, as

Rutherford continued purely scientific research. Thomson quickly realised that

Rutherford was a researcher of exceptional ability and invited him to join in a study of

the electrical conduction of gases.

Guglielmo Marconi

Guglielmo Marconi was an electrical engineer andNobel laureate known for the

development of a practical wireless telegraphy system.

In 1 96, Guglielmo Marconi was awarded a patent for radio with British Patent 1 039,

Improvements in Transmitting Electrical Impulses and Signals and inApparatus There-

for. This was the initial patent for the radio, though it used various earlier techniques ofvarious other experimenters (primarily Tesla) and resembled the instrument

demonstrated by others (including Popov). uring this time spark-gap wirelesstelegraphy was widely researched.

In 1 96, Bose went to London on a lecture tour and met Marconi, who was conducting

wireless experiments for the British post office. In 1 97, Marconi established the radiostation atNiton, Isle of Wight, England. In 1 97, Tesla applied for two key radio

patents in the USA. Those two patents were issued in early 1900. In 1 9 , Marconiopened a radio factory in all Street, Chelmsford, England, employing around 50

people. In 1 99, Bose announced his invention of the "iron-mercury-iron coherer withtelephone detector" in a paper presented at Royal Society, London.

Julio Cervera Baviera


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Julio Cervera Baviera

Recent studies in Spain creditJulio Cervera Baviera as the inventor ofthe radio (in

1902).[19]

[20]

Cervera Baviera obtained patents in England, Germany, Belgium, andSpain. In May-June 1899, Cervera had, with the blessing ofthe 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 awireless communication system, obtaining somepatents by the end of 1899. Cervera,who had worked with Marconi and his assistantGeorge Kempin 1899, resolved the

difficulties of wireless telegraph and obtained his first patents priorto the end ofthat

year. On March 22, 1902, Cervera founded the Spanish Wireless Telegraph andTelephone Corporation and broughtto his corporation the patents he had obtained in

Spain, Belgium, Germany and England.[21]

He established the second and third regularradiotelegraph service in the history ofthe world in 1901 and 1902 by maintaining

regulartransmissions between Tarifa and Ceuta forthree consecutive months, andbetween Javea (Cabo de la ao) and Ibiza (Cabo Pelado). This is afterMarconi

established the radiotelegraphic service between the Isle of Wight and Bournemouthin1898. In 1906, Domenico Mazzotto wrote:"In Spain the Minister of Warhas applied

the system perfected by the commander of military engineering, Julio Cervera Baviera(English patent o. 20084 (1899))."

[22]Cervera thus achieved some success in this field,

but his radiotelegraphic activities ceased suddenly, the reasons for which are unclearto

this day.[23]

Turn of the century

Around the turn ofthe century, the Slaby-Arco wireless system was developed by Adolf

Slaby and Georg von Arco. In 1900, Reginald Fessenden made a weaktransmission ofvoice overthe airwaves. Around 1900, Tesla opened the Wardenclyffe Towerfacility

and advertised services. In 1901, Marconi conducted the first successfultransatlanticexperimental radio communications. In 1903, Wardenclyffe Tower neared completion.

Various theories exist on how Tesla intended to achieve the goals ofthis wireless

system (reportedly, a 200 kW system). Tesla claimed that Wardenclyffe, as part of a

World System oftransmitters, would have allowed secure multichanneltransceiving of

information, universal navigation, time synchronization, and a globallocation system.

In 1904, The U.S. PatentOffice reversed its decision, awarding Marconi a patent forthe

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 commercialtransatlantic radio communications service, between

Clifden, Ireland and Glace Bay, ewfoundland.

Early radio telegraphy and telephony


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onald Manson working as an employee of the Marconi Company (England, 1906)

British Marconi

Using variouspatents, the company called British Marconi was established in 1 97 and

began communication betweencoast radio stations 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 19 3, owning all of its equipment and refusing to communicate with non-Marconiequipped 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 Telefunken was founded on May 7, 1903 as "Telefunken society for

wireless telefon" ofSiemens & alske (S & ) and the Allgemeine Elektri itts-Gesellschaft (General Electricity Company) as joint undertakings for radio engineering

in Berlin. It continued as a joint venture ofAEG and Siemens AG, until Siemens left in1941. In 1911, Kaiser Wilhelm II sent Telefunken engineers to West Sayville,New

Yorkto erect three 600-foot (1 0-m) radio towers there.Nikola Tesla assisted in theconstruction. A similar station was erected inNauen, creating the only wireless

communication betweenNorth America and Europe.

Reginald Fessenden

The invention of amplitude-modulated (AM) radio, so that more than one station cansend signals (as opposed to spark-gap radio, where one transmitter covers the entire

bandwidth of the spectrum) is attributed toReginald Fessenden and Lee de Forest. nChristmas Eve 1906, Reginald Fessenden used an Alexanderson alternatorand rotary

spark-gap transmitterto make the first radio audio broadcast, from Brant Rock,Massachusetts. Ships at sea heard a broadcast that included Fessenden playingO Holy

Nighton the violin and reading a passage from the Bible.

Ferdinand Braun

In 1909, Marconi and Karl Ferdinand Braun were awarded theNobel Pri e in Physics

for "contributions to the development of wireless telegraphy".

Charles David Herrold


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In April 1909 Charles avid errold, an electronics instructor in San Jose, California

constructed a broadcasting station. It used spark gap technology, but modulated the

carrier frequency with the human voice, and later music. The station "San Jose Calling"

(there were no call letters), continued to eventually become today sKCBS in San

Francisco. errold, the son of a Santa Clara alley 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 ageneral audience. (The term "broadcasting" had been used in farming to define thetossing of seed in all directions.) Charles errold did not claim to be the first to transmit

the human voice, but he claimed to be the first to conduct "broadcasting". To help theradio signal to spread in all directions, he designed some omnidirectional antennas,

which he mounted on the rooftops of various buildings in San Jose. erroldalso claimsto 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 usuallyisfoisted on WEAF (19 ).

RMS Titanic (A pril , 191 ).

In 191 , the RMS Titanic sank in the northern Atlantic cean. 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 andproduced a treaty requiring shipboard radio stations to be manned 4 hours a day. Atypical high-power spark gap was a rotating commutator with six to twelve contacts per

wheel, nine inches ( 9 mm) to a foot wide, driven by about 000volts C. As thegaps made and broke contact, the radio wave was audible as a tone in a crystal set. The

telegraph key often directly made and broke the 000 volt supply. ne side of the sparkgap was directly connected to the antenna. Receivers withthermionic valves became

commonplace before spark-gap transmitters were replaced by continuous wavetransmitters.

Harold J. Power

On March , 1916, arold Powerwith his radio company American Radio and

Research Company (AMRAD), broadcast the first continuous broadcast in the world

from Tufts University 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[

4].

Edwin Armstrong


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InventorEdwin Howard Armstrongis credited with developing many ofthe features of

radio as itis known today. Armstrong patented three importantinventions that madetoday's radio possible. Regeneration, the superheterodyne circuit and wide-band

frequency modulation or FM. Regeneration orthe use ofpositive feedbackgreatlyincreased 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 severaltuning controls. It made radios more sensitive and selective as well. FMgave listeners a static-free experience with better sound quality and fidelity than AM.

Other innovators

Many scientists and inventors contributed to the invention of wireless telegraphy and

telephony. Individuals that helped to furtherthe science include, among others:

y Georg von Arco: European pioneer.y Edouard Branly:invention ofthe Branly coherer around 1890.y Temistocle Calzecchi-Onesti: constructed a tuning "tube".y

Archie FrederickCollins:Arc transmitter for voice broadcasts, 1899.y Amos Dolbear: Earth transmission, U.S. Patent 350,299.y Thomas Alva Edison:"Etheric Force" experiments 1875; U.S. Patent 465,971,

1891.

y Michael Faraday: discovered electromagnetic induction.y Reginald Fessenden: advanced "continuous" wave transmission.y Benjamin Franklin: Firstto experiment with an elevated conductor.y Hans Christian rsted: discovered that a magnetic field surrounds a wire

carrying current.

y Joseph Henry:transmitted radiant energy from a capacitorthrough a coil anddetected it 100 feet (30 m) away, December 1840.

y Charles Herrold: advanced radio broadcasting.y David E. Hughes: early experiments with transmission and reception.y Mahlon Loomis: firstto use the combination of an aerial wire and ground

connection.

y Guglielmo Marconi: commercialized radio.y James ClerkMaxwell: developed a set ofequations expressing the basic laws of

electricity and magnetism.

y JozefMurga: extensive workin the late 1890s.y G. W. Pierce: circuits forcrystal oscillators for fixed-frequency operation.y William Henry Preece: early experiments in electromagnetism and wireless

telephony.

y Augusto Righi: continued Hertz's experiments.y Harry Shoemaker: 1901 to 1905; 40 patents.y Adolphus Slaby: European pioneer.y John Stone Stone: 1901 to 1904; 70 patents.y Nathan Stubblefield: wireless telephony demonstrations around 1902; U.S.

Patent887,357, 1908.

y Nikola Tesla: 1891 to 1914; 27+ patents related to the transmission of electricalenergy without wires.

Audio broadcasting (1919 to 1950s)


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See also: Old-time radio

Crystal sets

In the 19 0s, the United States government publication, "Construction and Operation of

a Simple Homemade Radio Receiving Outfit", showed how almost any person handywith simple tools could a build an effective crystal radio receiver.

The most common type of receiver before vacuum tubes was thecrystal set, although

some early radios used some type of amplification through electric current or battery.

Inventions of the triode amplifier, motor-generator, and detectorenabled audio radio.

The use ofamplitude 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 andLee 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 ofAmerica have often undertaken such craft projects to introduce boys to

electronics and radio, and quite a number of them having grown up remain staunch fansof 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 setcould produce, but with only moderately decent antenna systems remarkable

performance is possible with a superior set.

The first vacuum tubes

During the mid 19 0s, amplifyingvacuum tubes (orthermionic valves in the UK)

revolutioni ed radio receivers and transmitters. John Ambrose Fleming developed anearlier 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 anso Schotanus Steringa Id erdamade the first regularwireless broadcast for entertainment from his home in The ague on 6November 1919.

e broadcast his popular program four nights per week until 19 4 when he ran into

financial troubles.

On 7 August 19 0, regular wireless broadcasts for entertainment began in Argentina,

pioneered by the group aroundEnrique Tel maco Susini, and spark gap telegraphy

stopped. On 31 August 19 0 the first known radio news program was broadcast by

station MK, the unlicensed predecessor ofWWJ (AM) in Detroit, Michigan. In 19


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regular wireless broadcasts for entertainment began in the UK from the Marconi

Research Centre 2MT atWrittle nearChelmsford, England. Early radios ran the entirepower ofthe transmitterthrough a carbon microphone. In the 1920s, the Westinghouse

company boughtLee De Forest's and Edwin Armstrong's patent. During the mid 1920s,Amplifying vacuum tubes (US)/thermionic valves (UK) revolutionized radio receivers

and transmitters. Westinghouse engineers developed a more modern vacuum tube.

Licensed commercial public radio stations

The question ofthe 'first' publicly-targeted licensed radio station in the U.S. has more

than one answer and depends on semantics. Settlement ofthis 'first' question may hang

largely upon what constitutes 'regular' programming.

y Itis commonly attributed to KDKAin Pittsburgh, Pennsylvania, which inOctober 1920 received its license and went on the air as the first US licensed

commercial broadcasting station. (Their engineerFrankConrad 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.

y On February 17, 1919, station 9XM atthe University of Wisconsinin Madisonbroadcast human speech to the public atlarge. 9XM was first experimentally

licensed in 1914, began regularMorse codetransmissions in 1916, and its first

music broadcastin 1917. Regularly scheduled broadcasts of voice and music

began in January 1921. That station is still on the airtoday as WHA.

y On August20, 1920, atleasttwo months before KDKA, E.W. Scripps's WBL(now WWJ) in Detroit started broadcasting. It has carried a regular schedule of

programming to the present.

y There is the history noted above ofCharles David Herrold's radio services(eventually KCBS) going backto 1909.

Broadcasting was not yet supported by advertising orlistener sponsorship. The stationsowned by manufacturers and department stores were established to sell radios and those

owned by newspapers to sell newspapers and express the opinions ofthe 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 broughtinto the patent allies group, General Electric, American

Telephone and Telegraph, and Radio Corporation ofAmerica, and became a part ownerofRCA. All radios made by GE and Westinghouse were sold underthe RCAlabel 60%

GE and 40% Westinghouse. ATT's Western Electric would build radio transmitters. Thepatent allies attempted to set up a monopoly, butthey failed due to successful

competition. Much to the dismay ofthe patent allies, several ofthe contracts forinventor's patents held clauses protecting "amateurs" and allowing them to use the

patents. Whetherthe competing manufacturers were really amateurs was ignored by

these competitors.

These features arose:

y Commercial (United States) or governmental (Europe) station networksy FederalRadio Commission


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y FederalCommunications Commissiony CCIRy Birth ofthe soap operay Race towards shorter waves and FM

Dates of first radio stations

This is a listing ofradio stationsin broadcast networks. The earliest radio stations were

simply radio telegraph systems which did not carry audio are notlisted. The included

first radio station encompass AM and FM stations; these include both commercial,

public and nonprofit varieties found throughoutthe world.

NoteThe 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 ofthe dates listed here may not be accurate. Feel free to make corrections

to either ofthe lists.

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