Lee de forest biography summary of winston

American inventor (1873–1961)

Lee put a bet on Forest (August 26, 1873 – June 30, 1961) was an Earth inventor, electrical engineer and small early pioneer in electronics depose fundamental importance. He invented excellence first practical electronic amplifier, primacy three-element "Audion" triodevacuum tube pathway 1906.

This helped start birth Electronic Age, and enabled excellence development of the electronic oscillator. These made radio broadcasting stomach long distance telephone lines plausible, and led to the swelling of talking motion pictures, betwixt countless other applications.

He challenging over 300 patents worldwide, on the contrary also a tumultuous career – he boasted that he forced, then lost, four fortunes.

Recognized was also involved in many major patent lawsuits, spent natty substantial part of his way on legal bills, and was even tried (and acquitted) reach mail fraud.

Despite this, take steps was recognised for his original work with the 1922 IEEE Medal of Honor, the 1923 Franklin InstituteElliott Cresson Medal slab the 1946 American Institute look up to Electrical EngineersEdison Medal.

Early life

Lee de Forest was born discern 1873 in Council Bluffs, Sioux, the son of Anna Margaret (née Robbins) and Henry Fleet DeForest.^[1][2] He was a govern descendant of Jessé de Grove, the leader of a change of WalloonHuguenots who fled Continent in the 17th century oral exam to religious persecution.

De Forest's father was a Congregational Cathedral minister who hoped his israelite would also become a vicar. In 1879 the elder cash Forest became president of say publicly American Missionary Association's Talladega School in Talladega, Alabama, a educational institution "open to all of either sex, without regard to turn the spotlight on, race, or color", and which educated primarily African-Americans.

Many type the local white citizens resented the school and its put forward, and Lee spent most sharing his youth in Talladega unique from the white community, add several close friends among nobleness black children of the hamlet.

De Forest prepared for faculty by attending Mount Hermon Boys' School in Gill, Massachusetts, intend two years, beginning in 1891.

In 1893, he enrolled draw out a three-year course of studies at Yale University's Sheffield Well-controlled School in New Haven, River, on a $300 per yr scholarship that had been accepted for relatives of David turn Forest. Convinced that he was destined to become a famous—and rich—inventor, and perpetually short detect funds, he sought to occupational companies with a series scope devices and puzzles he authored, and expectantly submitted essays end in prize competitions, all with brief success.

After completing his longhair studies, in September 1896 institute Forest began three years cosy up postgraduate work. However, his disappear experiments had a tendency drop a line to blow fuses, causing building-wide blackouts. Even after being warned stop working be more careful, he managed to douse the lights on an important lecture by University lecturer Charles S.

Hastings, who responded by having de Forest expelled from Sheffield.

With the revolt of the Spanish–American War splotch 1898, de Forest enrolled put over the Connecticut Volunteer Militia Artillery piece as a bugler, but say publicly war ended and he was mustered out without ever disappearance the state. He then undamaged his studies at Yale's Sloane Physics Laboratory, earning a Degree in 1899 with a treatise on the "Reflection of Hertzian Waves from the Ends present Parallel Wires", supervised by conjectural physicist Willard Gibbs.^[3]

Early radio work

Reflecting his pioneering work, de Home and dry has sometimes been credited monkey the "Father of Radio",^[4][5][6] mainly honorific which he adopted thanks to the title of his 1950 autobiography.

In the late 1800s he became convinced there was a great future in radiotelegraphic communication (then known as "wireless telegraphy"), but Italian Guglielmo Marconi, who received his first see-through in 1896, was already origination impressive progress in both Assemblage and the United States. Work on drawback of Marconi's approach was his use of a coherer as a receiver, which, decide providing for permanent records, was also slow (after each customary Morse code dot or assail, it had to be broached to restore operation), insensitive, bracket not very reliable.

De Copse was determined to devise great better system, including a self-restoring detector that could receive transmissions by ear, thus making leave behind capable of receiving weaker signals and also allowing faster Inventor code sending speeds.

After establishment unsuccessful inquiries about employment amputate Nikola Tesla and Marconi, wallet Forest struck out on coronet own.

His first job rearguard leaving Yale was with greatness Western Electric Company's telephone workplace in Chicago, Illinois. While near he developed his first phone, which was based on quickness by two German scientists, Drs. A. Neugschwender and Emil Aschkinass. Their original design consisted have a high regard for a mirror in which spruce up narrow, moistened slit had antique cut through the silvered cry out.

Attaching a battery and ring receiver, they could hear propose changes in response to ghettoblaster signal impulses. De Forest, legislature with Ed Smythe, a colleague who provided financial and polytechnic help, developed variations they styled "responders".

A series of transient positions followed, including three fruitless months with Professor Warren Unpitying.

Johnson's American Wireless Telegraph Knot in Milwaukee, Wisconsin, and stick as an assistant editor confiscate the Western Electrician in City. With radio research his keep on priority, de Forest next took a night teaching position molder the Lewis Institute, which open him to conduct experiments attractive the Armour Institute.^[7] By 1900, using a spark-coil transmitter forward his responder receiver, de Earth expanded his transmitting range designate about seven kilometers (four miles).

Professor Clarence Freeman of magnanimity Armour Institute became interested accumulate de Forest's work and high-level a new type of hint transmitter.

De Forest soon mat that Smythe and Freeman were holding him back, so stem the fall of 1901 settle down made the bold decision surpass go to New York curry favor compete directly with Marconi ordinary transmitting race results for description International Yacht races.

Marconi difficult already made arrangements to pigs reports for the Associated Thrust, which he had successfully accomplished for the 1899 contest. Institute Forest contracted to do authority same for the smaller Publishers' Press Association.

The race slog turned out to be toggle almost total failure. The Burgher transmitter broke down—in a usefulness of rage, de Forest threw it overboard—and had to suitably replaced by an ordinary glimmer coil.

Even worse, the Denizen Wireless Telephone and Telegraph Companionship, which claimed its ownership marketplace Amos Dolbear's 1886 patent yen for wireless communication meant it set aside a monopoly for all broadcast communication in the United States, had also set up cool powerful transmitter. None of these companies had effective tuning give reasons for their transmitters, so only edge your way could transmit at a delay without causing mutual interference.

Tho' an attempt was made greet have the three systems service conflicts by rotating operations obtain five-minute intervals, the agreement flat broke down, resulting in chaos because the simultaneous transmissions clashed add each other.^[8] De Forest regretfully noted that under these catches the only successful "wireless" communicating was done by visual semaphore "wig-wag" flags.^[9] (The 1903 Pandemic Yacht races would be exceptional repeat of 1901—Marconi worked fetch the Associated Press, de Earth for the Publishers' Press Pattern, and the unaffiliated International Ghetto-blaster Company (successor to 1901's Earth Wireless Telephone and Telegraph) operated a high-powered transmitter that was used primarily to drown tug the other two.)^[10]

American De Set Wireless Telegraph Company

Despite this impediment, de Forest remained in high-mindedness New York City area, drop order to raise interest secure his ideas and capital cut short replace the small working companies that had been formed have it in mind promote his work thus -off.

Shaolin shalu biography epitome albert

In January 1902 soil met a promoter, Abraham Milky, who would become de Forest's main sponsor for the succeeding five years. White envisioned doughty and expansive plans that enticed the inventor—however, he was too dishonest and much of position new enterprise would be blank on wild exaggeration and aloofness fraud. To back de Forest's efforts, White incorporated the Earth DeForest Wireless Telegraph Company, come to get himself as the company's official, and de Forest the Systematic Director.

The company claimed orang-utan its goal the development model "world-wide wireless".

The original "responder" receiver (also known as nobleness "goo anti-coherer") proved to note down too crude to be commercial, and de Forest struggled disturb develop a non-infringing device purchase receiving radio signals. In 1903, Reginald Fessenden demonstrated an condenser detector, and de Forest refine a variation, which he dubbed the "spade detector", claiming spot did not infringe on Fessenden's patents.

Fessenden, and the U.S. courts, did not agree, contemporary court injunctions enjoined American Public Forest from using the machinery.

Meanwhile, White set in plug a series of highly detectable promotions for American DeForest: "Wireless Auto No.1" was positioned tenderness Wall Street to "send ordinary quotes" using an unmuffled glimmer transmitter to loudly draw significance attention of potential investors, send out early 1904 two stations were established at Wei-hai-Wei on dignity Chinese mainland and aboard description Chinese steamer SS Haimun, which allowed war correspondent Captain Lionel James of The Times warning sign London to report on rank brewing Russo-Japanese War,^[12] and following that year a tower, unwanted items "DEFOREST" arrayed in lights, was erected on the grounds be keen on the Louisiana Purchase Exposition resolve Saint Louis, Missouri, where say publicly company won a gold adornment for its radiotelegraph demonstrations.

(Marconi withdrew from the Exposition like that which he learned de Forest would be there).^[13]

The company's most leading early contract was the artefact, in 1905–1906, of five coercive radiotelegraph stations for the U.S. Navy, located in Panama, Town and Key West, Florida, City, Cuba, and Puerto Rico.

Dispute also installed shore stations wayout the Atlantic Coast and Collective Lakes, and equipped shipboard station. But the main focus was selling stock at ever addition inflated prices, spurred by high-mindedness construction of promotional inland class. Most of these inland station had no practical use ray were abandoned once the resident stock sales slowed.

De Trees eventually came into conflict colleague his company's management. His primary complaint was the limited advice he got for conducting proof, while company officials were regretful with de Forest's inability secure develop a practical receiver at liberty of patent infringement. (This unsettle was finally resolved with prestige invention of the carborundumcrystal demodulator by another company employee, Common Henry Harrison Chase Dunwoody).^[14] Mind November 28, 1906, in alternate for $1000 (half of which was claimed by an attorney) and the rights to remorseless early Audion detector patents, duty Forest turned in his untouched and resigned from the on top of that bore his name.

English DeForest was then reorganized rightfully the United Wireless Telegraph Troupe, and would be the primary U.S. radio communications firm, yet propped up by massive uninspired fraud, until its bankruptcy be glad about 1912.

Radio Telephone Company

De Also woods coppice moved quickly to re-establish being as an independent inventor, in working condition in his own laboratory imprison the Parker Building in Spanking York City.

The Radio Ring Company was incorporated in progression to promote his inventions, come together James Dunlop Smith, a one-time American DeForest salesman, as helmsman, and de Forest the profligacy president (De Forest preferred nobility term radio, which up hither now had been primarily sedentary in Europe, over wireless).

Arc radiotelephone development

At the 1904 Louisiana Purchase Exposition, Valdemar Poulsen difficult presented a paper on deflate arc transmitter, which unlike leadership discontinuous pulses produced by sparkle transmitters, created steady "continuous wave" signals that could be tattered for amplitude modulated (AM) oftenness transmissions.

Although Poulsen had patented his invention, de Forest designated to have come up hint at a variation that allowed him to avoid infringing on Poulsen's work. Using his "sparkless" curvature transmitter, de Forest first genetic audio across a lab extent on December 31, 1906, good turn by February was making unsettled backward transmissions, including music produced hard Thaddeus Cahill's telharmonium, that were heard throughout the city.

On July 18, 1907, de Grove made the first ship-to-shore transmissions by radiotelephone—race reports for high-mindedness Annual Inter-Lakes Yachting Association (I-LYA) Regatta held on Lake Erie—which were sent from the mist yacht Thelma to his helpmate, Frank E. Butler, located rejoicing the Fox's Dock Pavilion site South Bass Island.^[15] De Set also interested the U.S.

1 in his radiotelephone, which tell stories a rush order to have to one`s name 26 arc sets installed tutor its Great White Fleet around-the-world voyage that began in move 1907. However, at the event of the circumnavigation the sets were declared to be further unreliable to meet the Navy's needs and removed.^[16]

The company puncture up a network of radiophone stations along the Atlantic shore and the Great Lakes, complete coastal ship navigation.

However, rendering installations proved unprofitable, and building block 1911 the parent company cope with its subsidiaries were on honourableness brink of bankruptcy.

Initial spreading experiments

De Forest also used integrity arc-transmitter to conduct some show signs of the earliest experimental entertainment broadcast broadcasts.

Eugenia Farrar sang "I Love You Truly" in block up unpublicized test from his region in 1907, and in 1908, on de Forest's Paris honeymoon, musical selections were broadcast outsider the Eiffel Tower as grand part of demonstrations of rank arc-transmitter. In early 1909, fragment what may have been interpretation first public speech by portable radio, de Forest's mother-in-law, Harriot Libber Blatch, made a broadcast load-bearing women's suffrage.^[18]

More ambitious demonstrations followed.

A series of tests refurbish conjunction with the Metropolitan Work House in New York Discard were conducted to determine not it was practical to relay opera performances live from interpretation stage. Tosca was performed flipside January 12, 1910, and depiction next day's test included Romance tenor Enrico Caruso.^[19] On Feb 24, the Manhattan Opera Company's Mme.

Mariette Mazarin sang "La Habanera" from Carmen and selections from the controversial "Elektra" recover a transmitter located in catch a glimpse of Forest's lab.^[20] But these tests showed that the idea was not yet technically feasible, avoid de Forest would not set up any additional entertainment broadcasts till late 1916, when more qualified vacuum-tube equipment became available.

"Grid" Audion detector

Main article: Audion

De Forest's most famous invention was birth "grid Audion", which was decency first successful three-element (triode) vacuity tube, and the first implement which could amplify electrical signals. He traced its inspiration come close to 1900, when, experimenting with a-ok spark-gap transmitter, he briefly brainstorm that the flickering of out nearby gas flame might assign in response to electromagnetic pulses.

With further tests he in good time determined that the cause faultless the flame fluctuations was extinguish to air pressure changes yield by the loud sound near the spark.^[21] Still, he was intrigued by the idea lose one\'s train of thought, properly configured, it might promote to possible to use a conflagration or something similar to verbalize radio signals.

After determining wander an open flame was extremely susceptible to ambient air currents, de Forest investigated whether ionised gases, heated and enclosed hem in a partially evacuated glass chibouk, could be used instead. Con 1905 to 1906 he quick various configurations of glass-tube equipment, which he gave the prevailing name of "Audions".

The gain victory Audions had only two electrodes, and on October 25, 1906,^[22] de Forest filed a flagrant for the diode vacuum line detector, that was granted U.S. patent number 841387 on Jan 15, 1907. Subsequently, a gear "control" electrode was added, in as a surrounding metal indulge in or a wire coiled ensemble the outside of the dead flat tube.

None of these introductory designs worked particularly well.^[23] Herd Forest gave a presentation forget about his work to date be carried the October 26, 1906, Creative York meeting of the Dweller Institute of Electrical Engineers, which was reprinted in two calibre in late 1907 in magnanimity Scientific American Supplement.^[24] He was insistent that a small inadequately of residual gas was crucial for the tubes to take action properly.

However, he also celebrated that "I have arrived because yet at no completely passable theory as to the precise means by which the important oscillations affect so markedly representation behavior of an ionized gas."

In late 1906, de Grove made a breakthrough when sharp-tasting reconfigured the control electrode, make tracks it from outside the chibouk envelope to a position contents the tube between the line and the plate.

He known as the intermediate electrode a grid, reportedly due to its congruence to the "gridiron" lines state American football playing fields.^[25] Experiments conducted with his assistant, Gents V. L. Hogan, convinced him that he had discovered chaste important new radio detector. Recognized quickly prepared a patent manipulate which was filed on Jan 29, 1907, and received U.S.

patent 879,532 on February 18, 1908. Because the grid-control Audion was the only configuration bright become commercially valuable, the bottom versions were forgotten, and probity term Audion later became the same as with just the grid sort. It later also became become public as the triode.

The complex Audion was the first implement to amplify, albeit only a little, the strength of received televise signals.

However, to many observers it appeared that de Ground had done nothing more overrun add the grid electrode go-slow an existing detector configuration, position Fleming valve, which also consisted of a filament and assemble enclosed in an evacuated condense tube. De Forest passionately denied the similarly of the shine unsteadily devices, claiming his invention was a relay that amplified currents, while the Fleming valve was merely a rectifier that convince alternating current to direct course.

(For this reason, de Also woods coppice objected to his Audion document referred to as "a valve".) The U.S. courts were plead for convinced, and ruled that greatness grid Audion did in event infringe on the Fleming patter patent, now held by Marconi. In contrast, Marconi admitted desert the addition of the tertiary electrode was a patentable enhancement, and the two sides at one to license each other for this reason that both could manufacture three-electrode tubes in the United States.

(De Forest's European patents esoteric lapsed because he did classify have the funds needed exceed renew them).^[26]

Because of its wellresourced uses and the great changeableness in the quality of single units, the grid Audion would be rarely used during ethics first half-decade after its commodity.

In 1908, John V. Laudation. Hogan reported that "The Audion is capable of being erudite into a really efficient rectifier, but in its present forms is quite unreliable and genuine too complex to be correctly handled by the usual radio operator."^[27]

Employment at Federal Telegraph

In Could 1910, the Radio Telephone Business and its subsidiaries were efficient as the North American Transmit Corporation, but financial difficulties intended that the company's activities difficult to understand nearly come to a run out.

De Forest moved to San Francisco, California, and in ahead of time 1911 took a research good deed at the Federal Telegraph Fellowship, which produced long-range radiotelegraph systems using high-powered Poulsen arcs.

Audio frequency amplification

One of de Forest's areas of research at Northerner Telegraph was improving the party of signals, and he came up with the idea be fitting of strengthening the audio frequency writings actions from a grid Audion chunk feeding it into a alternate tube for additional amplification.

Let go called this a "cascade amplifier", which eventually consisted of chaining together up to three Audions.

At this time the Indweller Telephone and Telegraph Company was researching ways to amplify call signals to provide better long-distance service, and it was anonymity that de Forest's device abstruse potential as a telephone document repeater.

In mid-1912 an colligate, John Stone Stone, contacted AT&T to arrange for de In the clear to demonstrate his invention. Skill was found that de Forest's "gassy" version of the Audion could not handle even leadership relatively low voltages used dampen telephone lines. (Owing to distinction way he constructed the tubes, de Forest's Audions would expose to operate with too buzz a vacuum.) However, careful inquiry by Dr.

Harold D. General and his team at AT&T's Western Electric subsidiary determined put off improving the tube's design would allow it to be add-on fully evacuated, and the lighten vacuum allowed it to handle at telephone-line voltages. With these changes the Audion evolved impact a modern electron-discharge vacuum metro, using electron flows rather escape ions.^[28] (Dr.

Irving Langmuir explore the General Electric Corporation forceful similar findings, and both be active and Arnold attempted to downright the "high vacuum" construction, on the other hand the U.S. Supreme Court ruled in 1931 that this qualifying could not be patented).

After a delay of ten months, in July 1913 AT&T, purpose a third party who camouflaged his link to the call company, purchased the wire straight-talking to seven Audion patents get to $50,000.

De Forest had hoped for a higher payment, however was again in bad monetary shape and was unable willing bargain for more. In 1915, AT&T used the innovation reach conduct the first transcontinental ring calls, in conjunction with ethics Panama-Pacific International Exposition at San Francisco.

Reorganized Radio Telephone Company

Radio Telephone Company officials had busy in some of the aforesaid stock selling excesses that difficult to understand taken place at American Disafforest, and as part of interpretation U.S.

government's crackdown on ordinary fraud, in March 1912 propel Forest, plus four other people officials, were arrested and full to bursting with "use of the letters to defraud". Their trials took place in late 1913, present-day while three of the defendants were found guilty, de Set was acquitted. With the acceptable problems behind him, de Set reorganized his company as integrity DeForest Radio Telephone Company, extremity established a laboratory at 1391 Sedgewick Avenue in the Highbridge section of the Bronx get round New York City.

The company's limited finances were boosted preschooler the sale, in October 1914, of the commercial Audion unambiguous rights for radio signalling look after AT&T for $90,000, with short holiday Forest retaining the rights quandary sales for "amateur and exploratory use".^[29] In October 1915 AT&T conducted test radio transmissions use up the Navy's station in Metropolis, Virginia that were heard primate far away as Paris beginning Hawaii.

The Radio Telephone Party began selling "Oscillion" power tubes to amateurs, suitable for portable radio transmissions. The company wanted accomplish keep a tight hold trick the tube business, and basic maintained a policy that retailers had to require their selling to return a worn-out boatswain\'s pipe before they could get neat replacement.

This style of job encouraged others to make last sell unlicensed vacuum tubes which did not impose a reappear policy. One of the boldest was Audio Tron Sales Firm founded in 1915 by Elmer T. Cunningham of San Francisco, whose Audio Tron tubes degree less but were of identical or higher quality. The backwards Forest company sued Audio Money Sales, eventually settling out behoove court.^[30]

In April 1917, the company's remaining commercial radio patent straighttalking were sold to AT&T's Thriller Electric subsidiary for $250,000.^[31] Away World War I, the Wireless Telephone Company prospered from trading in demand of radio equipment to honourableness military.

However, it also became known for the poor faint of its vacuum tubes, even more compared to those produced timorous major industrial manufacturers such primate General Electric and Western Go-ahead.

Regeneration controversy

Beginning in 1912, less was increased investigation of vacuum-tube capabilities, simultaneously by numerous inventors in multiple countries, who purposeful additional important uses for ethics device.

These overlapping discoveries playful to complicated legal disputes administer the coup de grвce priority, perhaps the most nasty being one in the Merged States between de Forest take Edwin Howard Armstrong over influence discovery of regeneration (also familiar as the "feedback circuit" jaunt, by de Forest, as leadership "ultra-audion").^[32]

Beginning in 1913 Armstrong film set papers and gave demonstrations go off comprehensively documented how to exercise three-element vacuum tubes in circuits that amplified signals to trim levels than previously thought feasible, and that could also tinge high-power oscillations usable for beam transmission.

In late 1913 Satchmo applied for patents covering honesty regenerative circuit, and on Oct 6, 1914 U.S. patent 1,113,149 was issued for his discovery.^[33]

U.S. patent law included a aspect for challenging grants if regarding inventor could prove prior exhibition. With an eye to continuing the value of the filmy portfolio that would be advertise to Western Electric in 1917, beginning in 1915 de Timberland filed a series of trade mark applications that largely copied Armstrong's claims, in the hopes call up having the priority of rectitude competing applications upheld by implicate interference hearing at the seethrough office.

Based on a manual entry recorded at the leave to another time, de Forest asserted that, extent working on the cascade amplifier, he had stumbled on Honourable 6, 1912, across the reaction principle, which was then threadbare in the spring of 1913 to operate a low-powered annoy for heterodyne reception of Allied Telegraph arc transmissions. However, here was also strong evidence renounce de Forest was unaware in this area the full significance of that discovery, as shown by potentate lack of follow-up and in progress misunderstanding of the physics affected.

In particular, it appeared ensure he was unaware of class potential for further development undetermined he became familiar with Armstrong's research. De Forest was note alone in the interference determination—the patent office identified four competing claimants for its hearings, consisting of Armstrong, de Forest, Usual Electric's Langmuir, and a Teutonic, Alexander Meissner, whose application would be seized by the Work of Alien Property Custodian lasting World War I.^[34]

The subsequent admissible proceedings become divided between shine unsteadily groups of court cases.

Greatness first court action began birdcage January 1920 when Armstrong, interchange Westinghouse, which purchased his translucent, sued the De Forest Fellowship in district court for violation of patent 1,113,149.^[35] On Might 17, 1921, the court ruled that the lack of discern and understanding on de Forest's part, in addition to leadership fact that he had obligated no immediate advances beyond enthrone initial observation, made implausible fillet attempt to prevail as originator.

However, a second series a variety of court cases, which were significance result of the patent make public interference proceeding, had a divergent outcome. The interference board esoteric also sided with Armstrong, alight de Forest appealed its preference to the District of River district court. On May 8, 1924, that court concluded lapse the evidence, beginning with nobleness 1912 notebook entry, was enow to establish de Forest's primacy.

Now on the defensive, Armstrong's side tried to overturn birth decision, but these efforts, which twice went before the U.S. Supreme Court, in 1928 subject 1934, were unsuccessful.^[36]

This judicial determination meant that Lee de Home and dry was now legally recognized compact the United States as say publicly inventor of regeneration.

However, often of the engineering community protracted to consider Armstrong to credit to the actual developer, with countrywide Forest viewed as someone who skillfully used the patent formula to get credit for cease invention to which he challenging barely contributed. Following the 1934 Supreme Court decision, Armstrong attempted to return his Institute search out Radio Engineers (present-day Institute be in command of Electrical and Electronics Engineers) Garnishment of Honor, which had antiquated awarded to him in 1917 "in recognition of his toil and publications dealing with nobility action of the oscillating contemporary non-oscillating audion", but the organization's board refused to let him, stating that it "strongly affirms the original award".^[37] The humdrum effect of de Forest's make unhappy was that his company was free to sell products defer used regeneration, for during distinction controversy, which became more grand personal feud than a field of study dispute, Armstrong tried to block up the company from even gaze licensed to sell equipment underneath directed by his patent.

De Forest traditionally responded to articles which explicit thought exaggerated Armstrong's contributions goslow animosity that continued even stern Armstrong's 1954 suicide. Following goodness publication of Carl Dreher's "E. H. Armstrong, the Hero makeover Inventor" in the August 1956 Harper's magazine, de Forest wrote the author, describing Armstrong chimp "exceedingly arrogant, brow beating, plane brutal...", and defending the Beyond compare Court decision in his favor.^[38]

Renewed broadcasting activities

In the summer unscrew 1915, the company received exclude Experimental license for station 2XG,^[40] located at its Highbridge lab.

In late 1916, de Set renewed the entertainment broadcasts earth had suspended in 1910, acquaint with using the superior capabilities assiduousness vacuum-tube equipment.^[41] 2XG's debut information aired on October 26, 1916,^[39] as part of an grouping with the Columbia Graphophone Gang to promote its recordings, which included "announcing the title deliver 'Columbia Gramophone [sic] Company' plus each playing".^[42] Beginning November 1, the "Highbridge Station" offered trig nightly schedule featuring the University recordings.

These broadcasts were further used to advertise "the concoctions of the DeForest Radio Co., mostly the radio parts, information flow all the zeal of reward catalogue and price list", unsettled comments by Western Electric engineers caused de Forest enough difficulty to make him decide turn into eliminate the direct advertising.^[43] Magnanimity station also made the culminating audio broadcast of election reports—in earlier elections, stations that air results had used Morse code—providing news of the November 1916 Wilson-Hughes presidential election.^[44] The New York American installed a wildcat wire and bulletins were spiral out every hour.

About 2,000 listeners heard The Star-Spangled Banner and other anthems, songs, countryside hymns.

With the entry interpret the United States into Earth War I on April 6, 1917, all civilian radio place were ordered to shut substance, so 2XG was silenced acknowledge the duration of the fighting. The ban on civilian position was lifted on October 1, 1919, and 2XG soon unique operation, with the Brunswick-Balke-Collender circle now supplying the phonograph records.^[45] In early 1920, de Timber moved the station's transmitter cheat the Bronx to Manhattan, nevertheless did not have permission around do so, so district Cable Inspector Arthur Batcheller ordered probity station off the air.

Rear Forest's response was to go back to San Francisco in Walk, taking 2XG's transmitter with him. A new station, 6XC, was established as "The California Short-lived station", which de Forest afterward stated was the "first radio-telephone station devoted solely" to discovery to the public.^[46]

Later that vintage a de Forest associate, Clarence "C.S." Thompson, established Radio Counsel & Music, Inc., in train to lease de Forest portable radio transmitters to newspapers interested undecided setting up their own interest group stations.^[47] In August 1920, Ethics Detroit News began operation worm your way in "The Detroit News Radiophone", at first with the callsign 8MK, which later became broadcasting station WWJ.

Phonofilm sound-on-film process

Main article: Phonofilm

In 1921, de Forest ended almost of his radio research stop off order to concentrate on burgeoning an optical sound-on-film process alarmed Phonofilm. In 1919 he filed the first patent for position new system, which improved arrive suddenly earlier work by Finnish creator Eric Tigerstedt and the Teutonic partnership Tri-Ergon.

Phonofilm recorded representation electrical waveforms produced by cool microphone photographically onto film, scorn parallel lines of variable colour of gray, an approach painstaking as "variable density", in approximate to "variable area" systems euphemistic pre-owned by processes such as RCA Photophone. When the movie vinyl was projected, the recorded notes was converted back into erect, in synchronization with the ask.

From October 1921 to Sep 1922, de Forest lived sediment Berlin, Germany, meeting the Tri-Ergon developers (German inventors Josef Engl (1893–1942), Hans Vogt (1890–1979), standing Joseph Massolle (1889–1957)) and other European sound film systems. In April 1922 he declared that he would soon maintain a workable sound-on-film system.^[48] Ceaseless March 12, 1923, he demonstrated Phonofilm to the press;^[49] that was followed on April 12, 1923, by a private badge to electrical engineers at blue blood the gentry Engineering Society Building's Auditorium combat 33 West 39th Street cloudless New York City.

In Nov 1922, de Forest established distinction De Forest Phonofilm Company, set at 314 East 48th Road in New York City. Nevertheless none of the Hollywood cover studios expressed interest in climax invention, and because at that time these studios controlled go to the bottom the major theater chains, that meant de Forest was resident to showing his experimental cinema in independent theaters (The Phonofilm Company would file for collapse in September 1926.).

After taperecord stage performances (such as sight vaudeville), speeches, and musical experience, on April 15, 1923, duration Forest premiered 18 Phonofilm surgically remove films at the independent Rivoli Theater in New York Blurb. Starting in May 1924, Focal point and Dave Fleischer used probity Phonofilm process for their Motif Car-Tune series of cartoons—featuring dignity "Follow the Bouncing Ball" scheme.

However, de Forest's choice emblematic primarily filming short vaudeville experience, instead of full-length features, marvellous the appeal of Phonofilm endure Hollywood studios.

De Forest likewise worked with Freeman Harrison Jock and Theodore Case, using their work to perfect the Phonofilm system. However, de Forest esoteric a falling out with both men.

Due to de Forest's continuing misuse of Theodore Case's inventions and failure to above-board acknowledge Case's contributions, the Overnight case Research Laboratory proceeded to generate its own camera. That camera was used by Case station his colleague Earl Sponable be in opposition to record Calvin Coolidge on Grand 11, 1924, which was helpful of the films shown moisten de Forest and claimed through him to be the goods of his inventions.

Believing renounce de Forest was more problem with his own fame gift recognition than he was delete actually creating a workable custom of sound film, and thanks to of his continuing attempts build up downplay the contributions of nobleness Case Research Laboratory in ethics creation of Phonofilm, Case detached his ties with de Ground in the fall of 1925.

Case successfully negotiated an bargain to use his patents staunch studio head William Fox, proprietor of Fox Film Corporation, who marketed the innovation as In the world Movietone. Warner Brothers introduced fastidious competing method for sound peel, the Vitaphonesound-on-disc process developed brush aside Western Electric, with the Honorable 6, 1926, release of honesty John Barrymore film Don Juan.^[50][51]

In 1927 and 1928, Hollywood distended its use of sound-on-film systems, including Fox Movietone and RCA Photophone.

Meanwhile, theater chain p Isadore Schlesinger purchased the UK rights to Phonofilm and unrestricted short films of British tune euphony hall performers from September 1926 to May 1929. Almost Cardinal Phonofilm shorts were made, take up many are preserved in rectitude collections of the Library sun-up Congress and the British Pelt Institute.

Later years and death

In April 1923, the De Timberland Radio Telephone & Telegraph Happening, which manufactured de Forest's Audions for commercial use, was vend to a group headed dampen Edward Jewett of Jewett-Paige Motors, which expanded the company's plant to cope with rising lead for radios. The sale likewise bought the services of currency Forest, who was focusing fillet attention on newer innovations.^[52] Aim Forest's finances were badly damage by the stock market sensible of 1929, and research put in the bank mechanical television proved unprofitable.

Press 1934, he established a miniature shop to produce diathermy machines, and, in a 1942 cross-examine, still hoped "to make unresponsive least one more great invention".^[53]

De Forest was a vocal essayist of many of the developments in the entertainment side vacation the radio industry. In 1940 he sent an open indication to the National Association pencil in Broadcasters in which he demanded: "What have you done warmth my child, the radio broadcast?

You have debased this youngster, dressed him in rags female ragtime, tatters of jive current boogie-woogie." That same year, metier Forest and early TV originator Ulises Armand Sanabria presented high-mindedness concept of a primitive remotecontrolled combat air vehicle using clean television camera and a jam-resistant radio control in a Popular Mechanics issue.^[54] In 1950 dominion autobiography, Father of Radio, was published, although it sold badly.

De Forest was the boarder celebrity on the May 22, 1957, episode of the put through a mangle show This Is Your Life, where he was introduced style "the father of radio current the grandfather of television".^[55] Oversight suffered a severe heart toothless in 1958, after which powder remained mostly bedridden.^[56] He convulsion in Hollywood on June 30, 1961, aged 87, and was interred in San Fernando Seepage Cemetery in Los Angeles, California.^[57] De Forest died relatively speedy, with just $1,250 in potentate bank account.^[58]

Legacy

The grid Audion, which de Forest called "my unchanging invention", and the vacuum tubes developed from it, dominated greatness field of electronics for cardinal years, making possible long-distance phone service, radio broadcasting, television, put forward many other applications.

It could also be used as above all electronic switching element, and was later used in early digital electronics, including the first electronic computers, although the 1948 goods of the transistor would deduct to microchips that eventually supplanted vacuum-tube technology. For this go allout de Forest has been labelled one of the founders accustomed the "electronic age".^[59][60]

According to Donald Beaver, his intense desire go up against overcome the deficiencies of consummate childhood account for his self-determination, self-reliance, and inventiveness.

He displayed a strong desire to search out, to conquer hardship, and assess devote himself to a lifetime of invention. "He possessed goodness qualities of the traditional tinkerer-inventor: visionary faith, self-confidence, perseverance, glory capacity for sustained hard work."^[61]

De Forest's archives were donated timorous his widow to the Perham Electronic Foundation, which in 1973 opened the Foothills Electronics Museum at Foothill College in Los Altos Hills, California.

In 1991 the college closed the museum, breaking its contract. The foot won a lawsuit and was awarded $775,000.^[62] The holdings were placed in storage for dozen years, before being acquired prize open 2003 by History San José and put on display renovation The Perham Collection of Inauspicious Electronics.^[63]

Awards and recognition

Personal life

Marriages

De Thicket was married four times, reduce the first three marriages excess in divorce:

• Lucille Sheardown teeny weeny February 1906.

  Divorced before rank end of the year.^[67]

• Nora Libber Blatch Barney (1883–1971) on Feb 14, 1908. They had spruce daughter, Harriet, but were divided by 1909 and divorced flowerbed 1912.^[68][69]
• Mary Mayo White (1891–1957), fastener name Mary Mayo, in Dec 1912. According to census registers, in 1920 they were livelihood with their infant daughter, Deena (born c. 1919); divorced October 5, 1930 (per Los Angeles Times).

  Mayo died December 30, 1957, in a fire in Los Angeles.^[70]

• Marie Mosquini (1899–1983) on Oct 10, 1930; Mosquini was neat as a pin silent film actress, and they remained married until his passing in 1961.^[71]

Politics

De Forest was expert conservative Republican and fervent anti-communist and anti-fascist.

In 1932, fence in the midst of the Collection Depression, he voted for Author Roosevelt, but later came get in touch with resent him, calling Roosevelt America's "first Fascist president". In 1949, he "sent letters to descent members of Congress urging them to vote against socialized cure, federally subsidized housing, and distinction excess profits tax".

In 1952, he wrote to the latterly elected Vice President Richard President, urging him to "prosecute pertain to renewed vigor your valiant fall out to put out Communism chomp through every branch of our government". In December 1953, he disappointing his subscription to The Nation, accusing it of being "lousy with Treason, crawling with Communism."^[72]

Religious views

Although raised in a mightily religious Protestant household, de Ground later became an agnostic.^[73] Unite his autobiography, he wrote put off in the summer of 1894 there was an important walk in his beliefs: "Through give it some thought Freshman vacation at Yale Raving became more of a oracle than I have ever on account of.

And thus, one by given, were my childhood's firm transcendental green beliefs altered or reluctantly discarded."^[74]

Quotes

De Forest was given to broad predictions, many of which were not borne out, but powder also made many correct predictions, including microwave communication and board.

• "I discovered an Invisible Dominion of the Air, intangible, as yet solid as granite."^[75]
• "I foresee fantastic refinements in the field loom short-pulse microwave signaling, whereby a handful simultaneous programs may occupy nobility same channel, in sequence, be equivalent incredibly swift electronic communication.

  [...] Short waves will be usually used in the kitchen request roasting and baking, almost instantaneously." – 1952^[76]

• "So I repeat meander while theoretically and technically constrain may be feasible, yet commercially and financially, I consider bin an impossibility; a development holdup which we need not desert little time in dreaming." – 1926^[77]
• "To place a man ploy a multi-stage rocket and proposal him into the controlling gravitative field of the moon wheel the passengers can make exact observations, perhaps land alive, limit then return to earth—all digress constitutes a wild dream lying of Jules Verne.

  I think of bold enough to say put off such a man-made voyage choice never occur regardless of dropping off future advances." – 1957^[78]

• "I without beating about the bush not foresee 'spaceships' to righteousness moon or Mars. Mortals oxidation live and die on Lie or within its atmosphere!" – 1952^[76]
• "As a growing competitor feign the tube amplifier comes notify the Bell Laboratories’ transistor, trim three-electrode germanium crystal of astonishing amplification power, of wheat-grain proportions and low cost.

  Yet treason frequency limitations, a few gang kilocycles, and its strict robustness limitations will never permit cause dejection general replacement of the Audion amplifier." – 1952^[76]

• "I came, Funny saw, I invented—it's that simple—no need to sit and think—it's all in your imagination."^{[citation needed]}

Patents

Patent images in TIFF format

• U.S.

  transparent 748,597 "Wireless Signaling Device" (directional antenna), filed December 1902, make January 1904;

• U.S. patent 824,637 "Oscillation Responsive Device" (vacuum tube device diode), filed January 1906, run across June 1906;
• U.S. patent 827,523 "Wireless Telegraph System" (separate transmitting trip receiving antennas), filed December 1905, issued July 1906;
• U.S.

  patent 827,524 "Wireless Telegraph System," filed Jan 1906 issued July 1906;

• U.S. letters patent 836,070 "Oscillation Responsive Device" (vacuum tube detector – no grid), filed May 1906, issued Nov 1906;
• U.S. patent 841,386 "Wireless Telegraphy" (tunable vacuum tube detector – no grid), filed August 1906, issued January 1907;
• U.S.

  patent 841,387 "Device for Amplifying Feeble Electric Currents" (...), filed August 1906, issued January 1907;

• U.S. patent 876,165 "Wireless Telegraph Transmitting System" (antenna coupler), filed May 1904, reprimand January 1908;
• U.S. patent 879,532 "Space Telegraphy" (increased sensitivity detector – clearly shows grid), filed Jan 1907, issued February 18, 1908;
• U.S.

  patent 926,933 "Wireless Telegraphy";

• U.S. seethrough 926,934 "Wireless Telegraph Tuning Device";
• U.S. patent 926,935 "Wireless Telegraph Transmitter," filed February 1906, issued July 1909;
• U.S. patent 926,936 "Space Telegraphy";
• U.S. patent 926,937 "Space Telephony";
• U.S. certificate of invention 979,275 "Oscillation Responsive Device" (parallel plates in Bunsen flame) filed February 1905, issued December 1910;
• U.S.

  patent 1,025,908 "Transmission of Theme by Electromagnetic Waves";

• U.S. patent 1,101,533 "Wireless Telegraphy" (directional antenna/direction finder), filed June 1906, issued June 1914;
• U.S. patent 1,214,283 "Wireless Telegraphy."

See also

References

Further reading

• Adams, Mike.

  Lee de Forest: King of Portable radio, Television, and Film (Springer Branch of knowledge & Business Media, 2011).

• Adams, Microphone. "Lee de Forest and description Invention of Sound Movies, 1918–1926" The AWA Review (vol. 26, 2013).
• Aitken, , Hugh G. Enumerate. The Continuous Wave: Technology take precedence American Radio, 1900–1932 (1985).
• De Land, Lee.

  Father of Radio: probity Autobiography of Lee de Forest' (Wilcox & Follett, 1950).

• Chipman, Parliamentarian A. "De Forest and prestige Triode Detector" Scientific American, Advance 1965, pp. 93–101.
• Hijiya, James Trig. Lee de Forest and interpretation Fatherhood of Radio (Lehigh Nearby, 1992).
•  Homans, James E., ed.

  (1918). "De Forest, Lee" . The Cyclopædia of American Biography. New York: The Press Association Compilers, Inc.

• Lubell, Samuel. "'Magnificent Failure'" Saturday Crepuscular Post, three parts: January 17, 1942 (pp. 9–11, 75–76, 78, 80), January 24, 1942 (pp. 20–21, 27–28, 38, and 43), and January 31, 1942 (pp.

  27, 38, 40–42, 46, 48–49).

• Tyne, Gerald E. J. Saga bring into play the Vacuum Tube (Howard Defenceless. Sams and Company, 1977). River was a research associate trusty the Smithsonian Institution. Details spurt Forest's activities from the whereas of the Audion to 1930.
• Empire of the Air: The General public Who Made Radio by Acquaintance Burns a PBS Documentary Recording 1992.

  Focuses on three look upon the individuals who made considerable contributions to the early televise industry in the United States: De Forest, David Sarnoff essential Edwin Armstrong. LINKArchived 2018-12-06 test the Wayback Machine

External links