Survey of Broadcasting: Assignment 1, Question 2:–Describe the economic and political dynamics that brought about the birth of RCA.–Videos

Posted on June 20, 2011. Filed under: Audio, Broadcasting, Business, Inventions, Mass Media, Radio, Technology | Tags: , , , , , , , , , , , , , , , , , , , , |

II. Describe the economic and political dynamics that brought about the birth of RCA.


        A hundred years ago radio or the wireless was used as a point-to-point communications device similar to the use of the telegraph and telephone using wires. 

   Radio waves instead of wires were used primarily in maritime communications to send messages from ship to ship and ship to shore.

   British-owned Marconi Company and its subsidiary,  Marconi Wireless Telegraph Company of America, dominated the radio industry and controlled important patents including the Fleming value invented by John Fleming.

Sir John Ambrose Fleming

The Fleming value or vacuum tube consisted of a metal plate and thin wire enclosed in a glass bulb. The device enable the translating of an alternating current, like a radio wave, into direct current that could be detected by a radio receiver.

   The challenge was the detection of weak radio signals by radio receivers. Lee De Forest solved this problem by his invention of the audion that amplified weak radio signals. This was accomplished using a modified Fleming value with a tiny wire grid between the wire and the plate. The wire grid acted as an amplifier and boasted weak radio signals millions of times so that radio signals could be easily detected.


Lee De Forest

AT&T Archives: Bottle of Magic


Radio Commentator Jean Shepherd Meets Lee De Forest During WW2


A small bit of Radio History, Lee De Forest Audion, Marconi

De Forest envisioned radio as a broadcasting medium where entertainment and information would be received by a wide audience with radio receivers.

 This was in sharp contrast to the then use of radios as wireless telegraphy and telephony or a point-to-point communication device.

   The Marconi Company sued De Forest for patent infringement in using the Fleming value.

Faced with legal challenges from both the Marconi Company and the stockholders of his own company, De Forest Radio Telephone Company, De Forest sold his right to the audion to American Telephone & Telegraph or AT&T.

AT&T in turn used the audion to amplify signals in long distant calls.

De Forest continued to manufacture audions to radio hobbyists and manufactured radios or wireless sets for the military in World War I.

   General Electric or GE was also interested in radio.

GE held the patent rights to the high-speed alternators that produced electrical current with much higher frequencies than ordinary generators.

These alternators were used as continuous radio-wave generators.

Reginald Fessendon had invented this alternator design and demonstrated that the human voice could be carried by continuous radio waves generated by this transmitter.

Reginald Fessendon

GE had also improved the vacuum tube used in radios.

    Westinghouse, a major rival of General Electric, was also interested in radio. Westinghouse had acquired the patent rights to both an improved vacuum tube and the heterodyn radio receiver that was invented by Reginald Fessenden.

   Also, Edwin Armstrong had improved the audion by developing a positive feedback regenerative circuit that increased radio wave reception by regeneration amplification.

Edwin Armstrong


RCA Radio Model RC Operation

This RC radio is among one of the first products marketed by RCA in and about 1921. Westinghouse produced this RC radio for RCA. It is a battery set and uses three 01A vacuum tubes. The circuit is Edwin Howard Armstrong first major discovery, the regenerative circuit patented in 1914.


   In summary, the patents for radio transmitters and receivers were held by a number of companies and individuals including British Marconi, American Marconi, General Electric (GE), Westinghouse, American Telephone and Telegraph (AT&T), Lee De Forest and Edwin Armstrong.

For radio to advance in the future would require the pooling of these patents among economic competitive rivals.

   When the United States entered World War I in April 1917, the Federal Government gave the United States Navy the responsibility for all radio operations.

The United States Navy took over all commercial radio stations including forty-five commercial and eight high-powered stations owned and operated by American Marconi.

The Navy also assumed responsibility and full liability for all patent infringement.

Thus companies doing radio research and development were free to pool discoveries to develop a better radio system.

This resulted in better radio transmitters, radio receivers and vacuum tubes when War World I ended in November 1918.

   After the war, the United States Navy wanted to retain its control and monopoly over their radio system.

However, public sentiment was against this idea. The Navy then announced it was no longer responsible for patent infringement law suits.

This immediately lead to the patent problems that existed prior to the outbreak of the war.

  The Marconi Company was trying to purchase from General Electric the exclusive use of the high-powered alternators developed during World War 1.

Should the Marconi Company  be successful, it would dominate the radio transmitter market in America.

The United States Federal Government went to GE to come up with a solution to the situation. GE did not want to sell its alternators to the Marconi Company and the U.S. Government was opposed to  Marconi Wireless Telegraph Company of America controlled by the  British Marconi Company to dominate the radio industry in America.

Given this economic and political pressure, the  Marconi Company agreed to sell American Marconi to a new American company, Radio Corporation of America or RCA.

The stockholders of Marconi Wireless Telegraph Company of America exchanged their stock for shares of stock in RCS and British Marconi got cash from General Electric.

   RCA was born on October 17, 1919 when  Marconi Wireless Telegraph Company of America became RCA.

RCA viewed radio not as a medium for mass communications by broadcasting but as a point-to-point communications device like the telegraph or telephone.

The RCA business model was focused on making money by sending wireless telegraph and telephony to Europe, Latin America and Asia.

    The patent infringement and law suit problem was solved by GE and RCA entering into a cross-licensing agreement which allowed each company to use the other company’s discoveries.

Since AT&T still owned the De Forest audion patent, the U.S. government pressured AT&T to sign a cross-licensing agreement with RCA.

Westinghouse, a major GE rival, also held several important radio related patents. With GE having a major ownership stake in RCA, Westinghouse started its own wireless company, International Radio Telegraph Company.

GE offered Westinghouse a large stake in RCA in exchange for placing Westinghouse’s patents in the patent pool.

    By 1921, the major stockholders of RCA were GE with 30% of the shares, Westinghouse with about 20%, AT&T with about 10% and another 4% held by the United Fruit Company.

The cross-licensing of patents solved the existing patent problem. The radio industry was divided up with AT&T’s Western Electric subsidiary manufacturing radio transmitters, GE and Westinghouse manufacturing radio receivers or equipment, and RCA selling the radio receivers and equipment.

What the architects of RCA had failed to recognize is the future of radio was in broadcasting–mass communications.

Radio broadcasting took off in the roaring 20s and continues today.



Background Articles and Videos

Radio History


1920’s the radio


When Radio Was #1


When Radio Was #2


When Radio Was #3


When Radio Was #4


When Radio Was #5


When Radio Was #6


When Radio Was #7



The beginning of Commercial Radio



“…RCA Corporation, founded as the Radio Corporation of America, was an electronics company in existence from 1919 to 1986. Currently, the RCA trademark is owned by the French conglomerate Technicolor SA through RCA Trademark Management S.A., a company owned by Technicolor. The trademark is used by Sony Music Entertainment and Technicolor, which licenses the name to other companies like Audiovox and TCL Corporation for products descended from that common ancestor.[2]


 RCA’s organization by General Electric

On August 4, 1914, the United Kingdom and France declared war on the German Empire and Austria-Hungary, following the German and Austrian invasions of their neighbors, including Serbia and the Russian Empire, which started World War I. Radio traffic across the Atlantic Ocean increased dramatically after the western Allies cut the German transatlantic submarine communication cables (telegraph-only at that time, well-before the first transatlantic telephone cable connected the United States with France in 1956.) Germany, Austria-Hungary, and their allies in Europe (the Central Powers) maintained contact with neutral countries in the Americas, such as the United States, Mexico, Brazil, Argentina, Chile, and Peru via long-distance radio communications, as well as via telegraph cables owned by neutral countries such as the Netherlands and Denmark.

In 1917, the U.S. Federal Government took charge of the patents owned by the major companies involved in radio manufacture in the United States in order to devote radio technology to the war effort. All production of radio equipment was allocated to the U.S. Army, U.S. Navy, U.S. Marine Corps, and the U.S. Coast Guard. The U.S. Department of War and the U.S. Department of the Navy sought to maintain a Federal monopoly of all uses of radio technology. However, the wartime takeover of all radio systems ended with the tabling of a bill to continue this by the U.S. Congress sometime in the latter part of 1918. {World War I ended on November 11th.)

The ending of the Federal Government’s monopoly in radio communications did not prevent the Departments of War and of the Navy from creating a national radio system for the United States.[3] On April 8, 1919, the naval and Admiral W. H. G. Bullard and Captain Stanford C. Hooper met with executives of the General Electric Corporation (G.E.) to ask that their corporation to discontinue selling any of its Alexanderson alternators (used in the high-power amplitude modulation radio transmitters of that era) to the British-owned Marconi Company, and to its subsidiary, the Marconi Wireless Telegraph Company of America.

The gist of the Army’s and Navy’s proposal was that if G.E. created an American-owned radio company, then the Army and Navy would be able to bring into effect a monopoly of long-distance radio communications via this company. This marked the beginning of a series of negotiations through which G.E. would buy the American Marconi company and then incorporate what would be called the Radio Corporation of America.[4]


The incorporation of the assets of Marconi Wireless Telegraph Company of America (including David Sarnoff[5]), the Pan-American Telegraph Company, and those already controlled by the United States Navy led to a new publicly held company formed by General Electric (which owned a controlling interest) on 17 October 1919.[6] The following cooperation among RCA, General Electric, the United Fruit Company, the Westinghouse Electric Corporation, and American Telephone & Telegraph (AT&T) brought about innovations in high-power radio technology, and also the founding of the National Broadcasting Company (NBC) in the United Sates. The Army and the Navy turned over the former American Marconi radio terminals (to RCA) that had been confiscated during World War I. (Note: there were no commercial radio stations anywhere in the world before 1922 when the station KDKA started broadcasting in Pittsburgh, Pennsylvania.) Admiral Bullard received a seat on the Board of Directors of RCA for his efforts in establishing RCA. The result was Federally-created monopolies in radio for GE and the Westinghouse Corporation and in telephone systems for the American Telephone & Telegraph Company.

The argument by the Department of War and the Department of the Navy that the usable radio frequencies were limited, and hence needed to be appropriated for use before other countries, such as the United Kingdom, France, Germany, and Canada monopolized them, collapsed in the mid-1920s following the discovery of the practicality of the use of the shortwave radio band (3.0 MHz though 30.0 MHz) for very long-range radio communications.[7]

The first chief executive officer of RCA was Owen D. Young;[8] David Sarnoff became its general manager. The documents of incorporation of RCA explicitly required it be mostly owned by Americans. RCA took over the marketing of the radio equipment of G.E. and Westinghouse Westinghouse, and in follow-on agreements, RCA also acquired the radio patents that had been held by Westinghouse and the United Fruit Company. As the years went on, RCA either took over, or produced for itself, a large number of patents, including that of the superheterodyne receiver.

Over the years, RCA continued to operate international telecommunications services, under its subsidiary RCA Communications, Inc., and later the RCA Global Communications Company. …”


John Ambrose Fleming

“…Sir John Ambrose Fleming (29 November 1849 – 18 April 1945) 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.[1] He is also famous for the left hand rule (for electric motors). …”

“…After leaving the University of Nottingham in 1882, Fleming took up the post of “Electrician” to the Edison Electrical Light Company, advising on lighting systems and the new Ferranti alternating current systems. In 1884 Fleming joined University College London taking up the Chair of Electrical Technology, the first of its kind in England. Although this offered great opportunities, he recalls in his autobiography that the only equipment provided to him was a blackboard and piece of chalk. In 1897 the Pender Laboratory was founding at University College, London and Fleming took up the Pender Chair after the £5000 was endowed as a memorial to John Pender, the founder of Cable and Wireless.[4] In 1899 Fleming became Scientific Advisor to the Marconi Company and soon after began work on the designing the power plant to enable the Marconi Company to transmit across the Atlantic.

In November 1904, he invented the two-electrode vacuum-tube rectifier, which he called the oscillation valve. He would later patent this invention.[5] It was also called a thermionic valve, vacuum diode, kenotron, thermionic tube, or Fleming valve. The Supreme Court of the United States later invalidated the patent because of an improper disclaimer and, additionally, maintained the technology in the patent was known art when filed.[6] This invention is often considered to have been the beginning of electronics, for this was the first vacuum tube.[7] Fleming’s diode was used in radio receivers and radars for many decades afterwards, until it was superseded by solid state electronic technology more than 50 years later.

Fleming retired from University College, London in 1927 at the age of 77. He remained active, becoming a committed advocate of the new technology of Television which included servicing as the first president of the Television Society.

John Ambrose Fleming (1906)

In 1906, Lee De Forest of the U.S. added a control “grid” to the valve to create a vacuum tube RF detector called the Audion, leading Fleming to accuse him of copying his ideas. De Forest’s device was shortly refined by him and Edwin H. Armstrong into the first electronic amplifier, a tube called the triode. The triode was vital in the creation of long-distance telephone and radio communications, radars, and early electronic digital computers (mechanical and electro-mechanical digital computers already existed using different technology). The court battle over these patents lasted for many years with victories at different stages for both sides. Fleming also contributed in the fields of photometry, electronics, wireless telegraphy (radio), and electrical measurements. He coined the term Power Factor to describe the true power flowing in an AC power system. He was knighted in 1929, and died at his home in Sidmouth, Devon in 1945. His contributions to electronic communications and radar were of vital importance in winning World War II. Fleming was awarded the IRE Medal of Honor in 1933 for “the conspicuous part he played in introducing physical and engineering principles into the radio art”.

Note from eulogy at the Centenary celebration of the invention of the thermionic valve:

One century ago, in November 1904, John Ambrose Fleming FRS, Pender Professor at UCL, filed GB 190424850  in Great Britain, for a device called the Thermionic Valve. When inserted together with a galvanometer, into a tuned electrical circuit, it could be used as a very sensitive rectifying detector of high frequency wireless currents, known as radio waves. It was a major step forward in the ‘wireless revolution’.

In November 1905, he patented the “Fleming Valve” (US 803684  ). As a rectifying diode, and forerunner to the triode valve and many related structures, it can also be considered to be the device that gave birth to modern electronics.

In the ensuing years, valves quickly superseded “cat’s whiskers” and were the main device used to create the huge electronics industry that we take for granted today. They remained dominant until the transistor took dominance in the early 1970s

Today, descendants of the original valve (or vacuum tube) still play an important role in a range of applications. They can be found in the power stages of radio and television transmitters, in some high-end audio amplifiers, as detectors of optical and short wavelength radiation, and in sensitive equipment that must be “radiation-hard”. …”

Lee De Forest

“…Lee De Forest (August 26, 1873 – June 30, 1961) 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 of electronics. He is also credited with one of the principal inventions which brought sound to motion pictures.

He was involved in several patent lawsuits and he spent a substantial part of his income from his inventions on the legal bills. He had four marriages and 25 companies, he was defrauded by business partners (as well as defrauding business partners himself), and he was once indicted for mail fraud, but was later acquitted.

He typically signed his name “Lee de Forest.”

He was a charter member of the Institute of Radio Engineers, one of the two predecessors of the IEEE (the other was the American Institute of Electrical Engineers).

DeVry University was originally named DeForest Training School, after Lee De Forest, by its founder Dr. Herman A. DeVry, who was a friend and colleague of De Forest’s.


De Forest had an interest in wireless telegraphy and he invented the Audion in 1906. He then developed an improved wireless telegraph receiver.

In January 1906, De Forest filed a patent for diode vacuum tube detector, a two-electrode device for detecting electromagnetic waves, a variant of the Fleming valve invented two years earlier. One year later, De Forest filed a patent for a three-electrode device that was a much more sensitive detector of electromagnetic waves. It was granted US Patent 879,532 in February 1908. The device was also called the De Forest valve, and since 1919 has been known as the triode. De Forest’s innovation was the insertion of a third electrode, the grid, between the cathode (filament) and the anode (plate) of the previously invented diode. The resulting triode or three-electrode vacuum tube could be used as an amplifier of electrical signals, notably for radio reception. The Audion was the fastest electronic switching element of the time, and was later used in early digital electronics (such as computers). The triode was vital in the development of transcontinental telephone communications, radio, and radar after Nikola Tesla’s and Guglielmo Marconi’s progress in radio in the 1890s, until the 1948 invention of the transistor.

De Forest had, in fact, stumbled onto this invention via tinkering and did not completely understand how it worked. De Forest had initially claimed that the operation was based on ions created within the gas in the tube when, in fact, it was shown by others to operate with a vacuum in the tube. The American inventor Irving Langmuir of General Electric Corp. was the first to correctly explain the theory of operation of the device, and also to significantly improve it.


In 1904, a De Forest transmitter and receiver were set up aboard the steamboat Haimun operated on behalf of The Times, the first of its kind.[3] On July 18, 1907, De Forest broadcast the first ship-to-shore message from the steam yacht Thelma. The communication provided quick, accurate race results of the Annual Inter-Lakes Yachting Association (I-LYA) Regatta. The message was received by his assistant, Frank E. Butler of Monroeville, Ohio, in the Pavilion at Fox’s Dock located on South Bass Island on Lake Erie. DeForest disliked the term “wireless”, and chose a new moniker, “radio”. De Forest is credited with the birth of public radio broadcasting when on January 12, 1910, he conducted experimental broadcast of part of the live performance of Tosca and, the next day, a performance with the participation of the Italian tenor Enrico Caruso from the stage of Metropolitan Opera House in New York City.[4] [5]


De Forest came to San Francisco in 1910, and worked for the Federal Telegraph Company, which began developing the first global radio communications system in 1912. California Historical Landmark No. 836 is a bronze plaque at the eastern corner of Channing St. and Emerson Ave. in Palo Alto, California which memorializes the Electronics Research Laboratory at that location and De Forest for the invention of the three-element radio vacuum tube.

 Middle years

The United States Attorney General sued De Forest for fraud (in 1913) on behalf of his shareholders, stating that his claim of regeneration was an “absurd” promise (he was later acquitted). Nearly bankrupt with legal bills, De Forest sold his triode vacuum-tube patent to AT&T and the Bell System in 1913 for the bargain price of $50,000.

De Forest filed another patent in 1916 that became the cause of a contentious lawsuit with the prolific inventor Edwin Howard Armstrong, whose patent for the regenerative circuit had been issued in 1914. The lawsuit lasted twelve years, winding its way through the appeals process and ending up before the Supreme Court in 1926. The Supreme Court ruled in favor of De Forest, although the view of many historians is that the judgment was incorrect.[6]

Radio pioneer

In 1916, De Forest, from experimental radio station 2XG in New York City, broadcast the first radio advertisements (for his own products) and the first Presidential election report by radio in November 1916 for Charles Evans Hughes and Woodrow Wilson. A few months later, DeForest moved his tube transmitter to Highbridge, Bronx. [7] Like Charles Herrold in San Jose, California — who had been broadcasting since 1909 with call letters “FN”, “SJN”, and then “6XF” — De Forest had a license from the Department of Commerce for an experimental radio station, but, like Herrold, had to cease all broadcasting when the U.S. entered World War I in April 1917. From April 1920 to November 1921, DeForest broadcast from station 6XC at the California Theater at Market and Fourth Streets in San Francisco. In late 1921, 6XC moved its transmitter to Ocean View Drive in the Rockridge section of Oakland, California and became KZY.[8][9]

Just like Pittsburgh’s KDKA four years later in November 1920, DeForest used the Hughes/Wilson presidential election returns for his broadcast. The New York American installed a private wire and bulletins were sent out every hour. About 2000 listeners heard The Star-Spangled Banner and other anthems, songs, and hymns. DeForest went on to sponsor radio broadcasts of music, featuring opera star Enrico Caruso and many other events, but he received little financial backing.

In April 1923, the De Forest Radio Telephone & Telegraph Company, which manufactured De Forest’s Audions for commercial use, was sold to a coalition of automobile makers, who expanded the company’s factory to cope with rising demand for radios. The sale also bought the services of De Forest, who was focusing his attention on newer innovations.[10] …”


Reginald Aubrey Fessenden

“…Reginald Aubrey Fessenden (October 6, 1866 – July 22, 1932), 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. In his later career he received hundreds of patents for devices in fields such as high-powered transmitting, sonar, and television. …”

“…The development of a rotary-spark transmitter was something of a stop-gap measure, to be used until a superior approach could be perfected. Fessenden felt that, ultimately, a continuous-wave transmitter—one that produced a pure sine wave signal on a single frequency—would be far more efficient, particularly because it could be used for quality audio transmissions. His design idea was to take a basic electrical alternator, which normally operated at speeds that produced alternating current of at most a few hundred hertz, and greatly speed it up in order to create electrical currents at tens of kilohertz. Thus, the high-speed alternator would produce a steady radio signal when connected to an aerial. Then, by simply placing a carbon microphone in the transmission line, the strength of the signal could be varied in order to add sounds to the transmission—in other words, amplitude modulation would be used to impress audio on the radio frequency carrier wave. However, it would take many years of expensive development before even a prototype alternator-transmitter would be ready, and a few more years beyond that for high-power versions to become available.

Fessenden contracted with General Electric to help design and produce a series of high-frequency alternator-transmitters. In 1903, Charles Proteus Steinmetz of GE delivered a 10 kHz version which proved of limited use and could not be directly used as a radio transmitter. Fessenden’s request for a faster, more powerful unit was assigned to Ernst F. W. Alexanderson, and in August, 1906 he delivered an improved model which operated at a transmitting frequency of approximately 50 kHz, although with far less power than Fessenden’s rotary-spark transmitters.

The alternator-transmitter achieved the goal of transmitting quality audio signals, but the lack of any way to amplify the signals meant they were somewhat weak. On December 21, 1906, Fessenden made an extensive demonstration of the new alternator-transmitter at Brant Rock, showing its utility for point-to-point wireless telephony, including interconnecting his stations to the wire telephone network. A detailed review of this demonstration appeared in The American Telephone Journal.[2]

A few days later, two additional demonstrations took place, which appear to be the first audio radio broadcasts of entertainment and music ever made to a general audience—maybe. (Beginning in 1904, the U.S. Navy had broadcast daily time signals and weather reports, but these employed spark transmitters, transmitting in Morse code). On the evening of December 24, 1906 (Christmas Eve), Fessenden used the alternator-transmitter to send out a short program from Brant Rock. It included a phonograph record of Ombra mai fu (Largo) by George Frideric Handel, followed by Fessenden himself playing the song O Holy Night on the violin. Finishing with reading a passage from the Bible: ‘Glory to God in the highest and on earth peace to men of good will’ (Gospel of Luke 2:14).[3] He petitioned his listeners to write in about the quality of the broadcast as well as their location when they heard it. Surprisingly, his broadcast was heard several hundred miles away, however accompanying the broadcast was a disturbing noise. This noise was due to irregularities in the spark gap transmitter he used.[4]

On December 31, New Year’s Eve, a second short program was broadcast. The main audience for both these transmissions was an unknown number of shipboard radio operators along the East Coast of the United States. Fessenden claimed that the Christmas Eve broadcast had been heard “as far down” as Norfolk, Virginia, while the New Year Eve’s broadcast had reached places in the Caribbean. Although now seen as a landmark, these two broadcasts were barely noticed at the time and soon forgotten— the only first-hand account appears to be a letter Fessenden wrote on January 29, 1932 to his former associate, Samuel M. Kinter.[3] There are no known accounts in any ships’ radio logs, nor any contemporary literature, of the reported holiday demonstrations.

(Broadcasting historian James E. O’Neal, in a series of articles on the Radio World website [5] ,[6] suggests that Fessenden, writing a quarter-century after the fact, may have confused the dates; O’Neal suggests Fessenden was remembering instead a series of tests he’d conducted in 1909.)

There is solid historical evidence, however, that Fessenden’s demonstrations of “wireless telephony” were well know at the time. Documentation of Fessenden’s demonstration of radio-transmitted voice is provided by a New York Time’s article, dated Sunday, September 1, 1907, titled: “Telephoning at Sea”. It announced that the “Navy Department is about to install wireless telephone apparatus on all battleships destined for the Pacific, this Fall. Practicable wireless telephony over a distance of five miles in all weathers is guaranteed by the company furnishing the instruments. Under favorable conditions, it is reported, a much greater distance for communication is possible.” The article accurately describes the science involved, saying: “The Hertzian waves will penetrate opaque substances, and the amplitude and intensity of the waves may be so varied as to reproduce faithfully the vibrations of the human voice.” The same article further states that: “recently, the Fessenden wireless system demonstrated the practicability of transmitting spoken words from a tall mast at Brent Rock to Plymouth, twelve miles away.” [7] Intense competition among developers of wireless technology, and the expectation of possible government contracts may have limited the scope of public promotion of the apparatus features and capabilities.

Fessenden’s broadcast foreshadowed of the future of radio. (Although primarily designed for transmissions spanning a few kilometers, on a couple of occasions the test Brant Rock audio transmissions were apparently overheard by NESCO employee James C. Armor across the Atlantic at the Machrihanish site). …”

Edwin Howard Armstrong

“…Edwin Howard Armstrong (December 18, 1890 – January 31, 1954) was an American electrical engineer and inventor. Armstrong was the inventor of modern frequency modulation (FM) radio.

Edwin Howard Armstrong was born in New York City, New York, in 1890. He studied at Columbia University and later became a professor there. He invented the regenerative circuit while he was an undergraduate and patented it in 1914, the super-regenerative circuit (patented 1922), and the superheterodyne receiver (patented 1918).[2][3]

“…Work and patent disputes

Armstrong’s “feed back” circuit drawing, from Radio Broadcast vol. 1 no. 1 1922.

Howard Armstrong contributed the most to modern electronics technology. His discoveries revolutionized electronic communications. Regeneration, or amplification via positive feedback is still in use to this day. Also, Armstrong discovered that Lee De Forest’s Audion would go into oscillation when feedback was increased. Thus, the Audion could not only detect and amplify radio signals, it could transmit them as well.

While De Forest’s addition of a third element to the Audion (the grid) and the subsequent move to modulated (voice) radio is not disputed, De Forest did not put his device to work. Armstrong’s research and experimentation with the Audion moved radio reception beyond the crystal set and spark-gap transmitters. Radio signals could be amplified via regeneration to the point of human hearing without a headset. Armstrong later published a paper detailing how the Audion worked,[5] something De Forest could not do. De Forest did not understand the workings of his Audion.

Armstrong’s discovery and development of superheterodyne technology made radio receivers, then the primary communications devices of the time, more sensitive and selective. Before heterodyning, radio signals often overrode and interfered with each other. Heterodyning also made radio receivers much easier to use, rendering obsolete the multitude of tuning controls on radio sets of the time. The superheterodyne technology is still used today.

Armstrong is possibly best known for his discovery of wide-band frequency modulation. FM was born of a request by David Sarnoff of RCA as a means to eliminate static in radio reception. While Sarnoff was understandably impressed with Armstrong’s FM system, he also understood that it was not compatible with his own AM empire. Sarnoff came to see FM as a threat and refused to support it further.

Many of Armstrong’s inventions were ultimately claimed by others in patent lawsuits. In particular, the regenerative circuit, which Armstrong patented in 1914 as a “wireless receiving system,” was subsequently patented by Lee De Forest in 1916; De Forest then sold the rights to his patent to AT&T. Between 1922 and 1934, Armstrong found himself embroiled in a patent war, between himself, RCA, and Westinghouse on one side, and De Forest and AT&T on the other. At the time, this action was the longest patent lawsuit ever litigated, at 12 years. Armstrong won the first round of the lawsuit, lost the second, and stalemated in a third. Before the Supreme Court of the United States, De Forest was granted the regeneration patent in what is today widely believed to be a misunderstanding of the technical facts by the Supreme Court.[6]

By early 1923, Armstrong was a millionaire as a result of licensing his patents to RCA.[4]

In 1946 the FCC’s decision to use Armstrong’s FM system as the standard for NTSC television sound gave Armstrong another chance at royalty payments. However, RCA refused to pay royalties and encouraged other television makers not to pay them either. …”

…FM Radio

Even as the regenerative-circuit lawsuit continued, Armstrong was working on another momentous invention. While working in the basement laboratory of Columbia’s Philosophy Hall, he created wide-band frequency modulation radio (FM). Rather than varying the amplitude of a radio wave to create sound, Armstrong’s method varied the frequency of the wave instead. FM radio broadcasts delivered a much clearer sound, free of static, than the AM radio dominant at the time. (Armstrong received a patent on wide-band FM on December 26, 1933.[7]

In 1922, John Renshaw Carson of AT&T, inventor of Single-sideband modulation (SSB modulation), had published a paper in the Proceedings of the IRE arguing that FM did not appear to offer any particular advantage.[8] Armstrong managed to demonstrate the advantages of FM radio despite Carson’s skepticism in a now-famous paper on FM in the Proceedings of the IRE in 1936,[9] which was reprinted in the August 1984 issue of Proceedings of the IEEE.[10]

Today the consensus regarding FM is that narrow band FM is not so advantageous in terms of noise reduction, but wide band FM can bring great improvement in signal to noise ratio if the signal is stronger than a certain threshold. Hence Carson was not entirely wrong, and the Carson bandwidth rule for FM is still important today. Thus, both Carson and Armstrong ultimately contributed significantly to the science and technology of radio. The threshold concept was discussed by Murray G. Crosby (inventor of Crosby system for FM Stereo) who pointed out that for wide band FM to provide better signal to noise ratio, the signal should be above a certain threshold, according to his paper published in Proceedings of the IRE in 1937.[11] Thus Crosby’s work supplemented Armstrong’s paper in 1936.

Armstrong conducted the first large scale field tests of his FM radio technology on the 85th floor of RCA’s (Radio Corporation of America) Empire State Building from May 1934 until October 1935. However RCA had its eye on television broadcasting, and chose not to buy the patents for the FM technology.[12] A June 17, 1936, presentation at the Federal Communications Commission (FCC) headquarters made headlines nationwide. He played a jazz record over conventional AM radio, then switched to an FM broadcast. “[I]f the audience of 50 engineers had shut their eyes they would have believed the jazz band was in the same room. There were no extraneous sounds,” noted one reporter. He added that several engineers described the invention “as one of the most important radio developments since the first earphone crystal sets were introduced.”[13]

In 1937, Armstrong financed construction of the first FM radio station, W2XMN, a 40 kilowatt broadcaster in Alpine, New Jersey. The signal (at 42.8 MHz) could be heard clearly 100 miles (160 km) away, despite the use of less power than an AM radio station.[14]

RCA began to lobby for a change in the law or FCC regulations that would prevent FM radios from becoming dominant. By June 1945, the RCA had pushed the FCC hard on the allocation of electromagnetic frequencies for the fledgling television industry. Although they denied wrongdoing, David Sarnoff and RCA managed to get the FCC to move the FM radio spectrum from (42-50 MHz), to (88-108 MHz), while getting new low-powered community television stations allocated to a new Channel 1 in the 44-50 MHz range. In fairness to the FCC, the 42-50 MHz band was plagued by frequent tropospheric and E-layer stratospheric propagation which caused distant high powered stations to interfere with each other. The problem becomes even more severe on a cyclical basis when sunspot levels reach a maximum every 11 years and lower VHF band signals below 50 MHz can travel across the Atlantic Ocean or from coast to coast within North America on occasion. Sunspot levels were near their cyclical peak when the FCC reallocated FM in 1945. The 88-108 MHz range is a technically better location for FM broadcast because it is less susceptible to this kind of frequent interference. (Channel 1 eventually had to be deleted as well, with all TV broadcasts licensed at frequencies 54 MHz or higher, and the band is no longer widely used for emergency first responders either, those services having moved mostly to UHF.)

But the immediate economic impact of the shift, whatever its technical merit, was devastating to early FM broadcasters. This single FCC action would render all Armstrong-era FM receivers useless within a short time as stations were moved to the new band, and it also protected both RCA’s AM-radio stronghold and that of the other major competing networks, CBS, ABC and Mutual. Armstrong’s radio network did not survive the shift into the high frequencies and was set back by the FCC decision. This change was strongly supported by AT&T, because loss of FM relaying stations forced radio stations to buy wired links from AT&T.

Furthermore, RCA also claimed invention of FM radio and won its own patent on the technology. A patent fight between RCA and Armstrong ensued. RCA’s momentous victory in the courts left Armstrong unable to claim royalties on any FM receivers, including televisions, sold in the United States. The undermining of the Yankee Network and his costly legal battles brought ruin to Armstrong, by then almost penniless and emotionally distraught. Eventually, after Armstrong’s death, many of the lawsuits were decided or settled in his favor, greatly enriching his estate and heirs—but the decisions came too late for Armstrong himself to enjoy his legal vindication.

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