Sarnoff vs Farnsworth: The Battle for the Tube.

The future of television would be defined by its outcome.


Sarnoff, the president of the Radio Corporation of America (RCA) had spent his entire adult life rising up through the ranks of the American Marconi wireless telegraph company. David was a Russian immigrant who started as a mere office boy in 1906 at the age of 15, learning about electronics and wireless communications on-the-job. He served at Marconi radiotelegraph stations on ships and on shore, soon becoming a manager of the telegraphers, then chief inspector and contract manager. However, David wasn’t merely content to ride the radio wave of the present – rather, he was always looking toward the future, even then.

So was an Idaho farmboy named Philo T. Farnsworth.

David Sarnoff had already had some pretty big ideas.

The utility of the “wireless” had, to that point, been commonly seen as a point-to-point, two-way technology – you talked to the remote station, and they talked back. You had a conversation, and when you were done, others took your place, like a telephone. But there were the occasional “broadcast” messages, like weather reports, and that combined with news of voice transmission tests piqued Sarnoff’s interest. He wondered if new radio technologies could transmit music with any clarity, and so in 1915 he did a demonstration of his own, from a station in New York, broadcasting music to anyone who could – and wanted to – listen.

David wrote a memo to his superiors proposing the idea of a receiver-only radio set, one that would allow an owner to listen to music broadcasts passively, but his superiors scoffed at the idea and ignored him. Why would they congest the airwaves with rubbish like that, wasting valuable space that could be used for two-way communication? The radio, after all, was going to eventually replace the telephone, wasn’t it? Time went on. After World War I ended, General Electric bought American Marconi, and Sarnoff revived his idea, which once again was discounted. Why would anyone want to listen to an arbitrary sequence of songs over the radio when they could play whatever recordings they wanted? They could go to the music hall for that sort of thing. And newspapers did news – that’s what they were for! David’s “receiver” would never catch on. Going down that road would just waste the company’s time and money.

But Sarnoff was undeterred. In 1921 he helped to privately organise a “live” broadcast of a heavyweight boxing match between Georges Carpentier and Jack Dempsey and afterward, the public demand for radio receivers was palpable. Having adequately demonstrated an application of radio – live event coverage – that was unavailable to any other medium, David’s bosses at RCA had no choice but to journey with Sarnoff down his rabbit-hole, and in 1925 RCA purchased its first radio station in New York, launching the National Broadcasting Company (NBC) and placing Sarnoff at its helm. He would guide and grow the world’s first radio network for four years, before becoming the president of RCA. However Sarnoff wasn’t content.

David was aware of recent experiments regarding the transmission of moving images. Scottish inventor John Logie Baird had demonstrated the first working “television” (the term coined in 1900 by Russian engineer Konstantin Perskiy – vision meaning “to see” and tele signifying “over a distance”) in 1926, and Sarnoff deduced quite accurately that if the public had gone crazy over being able to hear a boxing match, they would go completely insane if they could actually see it. To say television was on Sarnoff’s radar would be a gross understatement indeed. But Baird’s system was mechanical, low definition and hard to see, and Sarnoff didn’t think it was practical. But eventually it would improve and then he would pounce, using RCA’s might to shut Baird out of the North American market, appropriating the Scotsman’s technology for itself, and taking all the credit (and the profits).

And so, when Sarnoff looked at his newspaper and saw that an American couple, Philo and Pem Farnsworth, had demonstrated not only a working television system but an all-electronic television system using the cathode-ray tube on both the transmission and receiving sides, and without the annoyances of its mechanical cousin – it was quieter, and the screen was brighter and larger – he quickly realised he had a problem. His first instinct was to buy the Farnsworths out, but he soon discovered they had investors – bankers that reportedly owned 60% of their company, and who weren’t going to sell cheaply. RCA hadn’t made its fortunes by being generous to others – in fact, Sarnoff was often accused of being a robber baron, and if he couldn’t get what he wanted one way, he would get it another.

Philo Farnsworth hadn’t had much of a choice. He needed money in order to pursue his invention, and that was the only offer on the table. Investing in television would seem like a no-brainer today, but at its birth it was considered an extremely risky investment – not only had inventors been chasing the dream (and spending money) for over two decades, but they still hadn’t adequately answered the question of whether anyone really wanted it enough to pay for it. But Farnsworth was convinced of television’s revolutionary potential, and had been ever since 1921, when he was fifteen and had drawn sketches of a proposed fully-electronic television system for his high school science teacher.

But Philo Farnsworth hadn’t had much of a choice. He needed money in order to pursue his invention, and that was the only offer on the table. Investing in television would seem like a no-brainer today, but at its birth it was considered an extremely risky investment – not only had inventors been chasing the dream (and spending money) for over two decades, but they still hadn’t adequately answered the question of whether anyone really wanted it enough to pay for it. But Farnsworth was convinced of television’s revolutionary potential, and had been ever since 1921, when he was fifteen and had drawn sketches of a proposed fully-electronic television system for his high school science teacher.

Born in 1906 in Utah, Philo T. Farnsworth moved to Rigby Idaho with his family in 1918 on to a relative’s 240-acre ranch. The farmhouse had an electric generator, and Philo soon found a cache of technology-related magazines in the attic. He was a quick study, learning how to perform repairs on the generator and fix burnt-out electric motors. But his young mind soon turned to larger problems. Philo began to contemplate the idea of all-electronic television, reportedly having an epiphany regarding the raster scanning (scanning sequentially in rows) process of an image using cathode rays while gazing upon the impressions left in a harvested Idaho wheat field, but the bulk of his proposed system was likely influenced by the work of Scottish engineer Alan Campbell-Swinton, whose extremely similar theoretical system of television Campbell-Swinton had first described in a letter to the British journal Nature in 1908, titled “Distant Electric Vision”, in which he described a system of two cathode-ray tubes.

Cathode rays were discovered in 1869 by German physicist Johann Hittorf. He had been experimenting with Crookes tubes, a glass bulb enclosing a partial vacuum, with two metal electrodes, one inserted at one end and the other suspended in the tube toward the other. When high-voltage was applied to the first electrode (the cathode), a stream of particles (later named electrons) would bridge across the vacuum to the other electrode (the anode), but more importantly, many would overshoot and “sparkle” as they hit the glass wall of the tube. A bit of fluorescent paint applied to the end of the tube showed that the electrons were travelling in straight lines, and hence the streams were called “cathode rays”. After British physicist William Crookes (the inventor of the Crookes tube) demonstrated that the direction of cathode rays could be controlled by magnetic fields (a concept improved upon by Campbell-Swinton), German Ferdinand Braun built the first proper cathode-ray tube in 1897, containing a phosphor-coated screen which he used to build the first oscilloscope, a device for visualising frequencies.

However, the number of electrons striking the screen in the Braun tube were few, and the light output was dim. An American physicist, John B. Johnson, developed a “hot cathode” tube, where the cathode is heated to increase the number of electrons emitted (this heating process is why older CRT-based televisions can sometimes take a few seconds to show a screen), and his tube entered commercial production in 1922, one year after Farnsworth’s presentation to his teacher. All-electronic television was now possible, someone only had to work out the details and build it.

Campbell-Swinton’s theoretical television system was featured in a 1915 issue of the popular American magazine Electrical Experimenter. It is much more likely a young Philo Farnsworth had encountered that article (maybe even in his attic), given the similarities between his system and Campbell-Swinton’s, and gained most of his initial inspiration there rather than inventing an entire television process in an Idaho wheat-field on his own, but regardless of where Farnsworth obtained his ideas, he was American; he was first to make it actually work (a remarkable achievement); and, worst of all, he was someone else’s property – making David Sarnoff’s only remaining advantage the wealth of RCA, which he could leverage with great abandon…and would.

The race was on.

Sarnoff met with Vladimir Zworykin, an engineer at American manufacturing company Westinghouse, who had studied in Russia under Boris Rosing, a Saint Petersburg scientist who had been working on television since 1902. Rosing demonstrated the first television of any kind in 1911, and Zworykin graduated the following year in 1912. He moved to the United States toward the end of the Russian Civil War and found work at Westinghouse engaging in television experiments, filing patents in 1923 and 1925.

Zworykin’s initial system was similar to Campbell-Swinton’s; it used the cathode-ray tube in both the transmitter and the receiver. Zworykin developed and patented a prototype receiver in 1929 he named the kinescope, and soon after spoke about it at a convention of the Institute of Radio Engineers. This garnered Sarnoff’s attention. He hired Zworykin away from Westinghouse in 1930, promising him virtually unlimited funds. Sarnoff didn’t care how Zworykin made television work, only that he did – and soon, before a competitor could upset RCA’s supremacy over the airwaves. But displaying the image was far less of a problem than capturing it. Zworykin was still using a mechanical device for that half of the television process and it wasn’t working out. He had toured Farnsworth’s laboratory toward the end of his time at Westinghouse and had been impressed by Farnsworth’s all-electronic “image dissector”, and believed a much better solution could be found there.

Two years after Philo’s impromptu presentation to his science teacher, he and his family had moved back to Utah, where he studied electronics at Brigham Young university. During this time he met his wife Elma Gardner, who went by the name Pem. After a brief foray into a radio repair business with Pem’s brother which failed, Farnsworth became acquainted with a pair of San Fransisco-based philanthropists who agreed to fund further research into his television ideas, and set up a laboratory for him in Los Angeles. Philo married Pem and they relocated to California, eager to begin their work.

Television experimentation to that point had employed a spinning mechanical disc to direct a “flying spot” of light systematically over the subject to be transmitted, using an electronic sensor to gauge the intensity of the light reflected back, and sending an electrical signal portraying that varying intensity to the receiver which could then reproduce it either using a variable light bulb and another spinning disc or using a cathode-ray tube (see Gadget Graveyard). This method was extremely restrictive – flying spot scanners were fixed in place and needed complete darkness. While improvements and variations in the method were developed, Farnsworth felt that capturing a television image should be as easy and straightforward as using a film camera, with all of the functionality they provided. And so, he developed a cathode-ray tube similar to the one Campbell-Swinton proposed.

Farnsworth’s image dissector tube contained a photocathode plate (a plate coated with a photosensitive material that emits negatively-charged electrons proportional to the amount of light it is exposed to) on one end. Lenses outside of the tube focussed an image on to the plate, and electrons were then released as a result, attracted to a positively-charged electrode (the anode) at the opposite end of the tube. However, an aperture (or small hole) only allowed a section of the electrons through, which would then hit the anode and create an electrical signal, measuring the light hitting the associated area on the plate. Rather than physically moving the aperture around in order to “scan” the complete image, magnetic fields were used to shift the flow of electrons from the plate, obtaining the same result with no moving parts.

It worked! In 1927 Farnsworth transmitted a simple straight line captured with the dissector, in 1928 he held his first demonstration for the press (where the first image transmitted was a dollar sign, a dig at his investors who “wanted to see money from this thing”), and by 1929 he was able to transmit a live image of Pem. But as most of the electrons released by the photocathode plate were blocked by the aperture the signal from the anode was weak, and it required an extreme amount of light to be cast on its subjects – the associated heat was unbearable, and as a result Pem’s eyes were closed when she became the dissector’s first human subject. Zworykin discounted the image dissector tube as ultimately impractical, and looked for another solution.

Zworykin had previously designed his own camera tube, which he had called the “Iconoscope”, and had filed a patent for it in 1925. It used an “image plate” made of aluminum oxide with an array of photo-sensitive potassium globules on one side and a metal mesh on the other, and a cathode-ray tube to scan it (we will describe this further in a moment.) But, while it worked, the resulting picture had poor resolution. Zworykin would abandon the Iconoscope and move on to other projects.

But now that he was at RCA, work on his camera tube began again in earnest. A breakthrough came in 1931 when one of Zworykin’s underlings, Sanford Essig, left one of the revised plates, made of mica rather than aluminium and coated in silver instead of potassium, baking in an oven too long. Upon examination, he noticed the silver layer had shattered into a large number of tiny silver globules, far more than they had been able to produce by manually placing each one. This would improve the resolution of the captured image substantially, creating the first practical picture.

The revised design worked by using a mica plate covered with an array of “cells” made up of photosensitive material, each of which had a grain of silver at its centre. A layer of silver was also applied to the back of the plate, causing each one of the cells to become a capacitor, able to store a charge, but never release it. Each one of those cells was like a pixel on a computer screen. A cathode-ray electron gun “charges up” the plate by scanning it. Then, a period of time passes while the photosensitive material coating each cell releases electrons depending on the amount of light hitting them from a lens-focussed image. The more light, the more electrons are released, and the more charge is dissipated.

The cathode-ray gun scans the plate again, and any electrons the cells cannot absorb are reflected back to a ring of metal around the sides of the tube. These collected electrons create an electronic representation of the image, a signal that can then be amplified and inverted, and then used to reconstruct the image using a cathode-ray “picture” tube. Zworykin rushed to patent the new design, late in 1931.

However, Farnsworth had patented many elements of his “camera tube” and that was going to eventually prove problematic for Sarnoff. In 1931 he offered to buy Farnsworth’s patents for US$100,000 but only if he went to work for RCA.

Despite investment having dried up in the wake of the 1929 stock market crash, Philo refused, and instead joined the Philco company in Philadelphia, Pennsylvania, moving there with Pem and their two children. Sarnoff retaliated by filing a patent-interference lawsuit against Farnsworth, claiming that Zworykin’s 1925 patent took precedence. To make matters worse, Sarnoff threatened to stop licensing RCA’s radio patents to Philco, and in 1933 it severed its relationship with Farnsworth. Things looked bleak for Philo, but his old high-school teacher had kept copies of some of his early diagrams, and he won the patent case. But Sarnoff threw his army of lawyers at Farnsworth, filing a number of appeals and injunctions.

By 1935 Philo had formed a new company, and he demonstrates a fully-functional television system in the summer of that year, but because of his patent fight with RCA nobody invests. At the invitation of John Logie Baird, Philo travels to Europe, not just to demonstrate his working system, but also in a quest to find funding for it, and he finds some success, licensing his image dissector tube to a German company, which used it to broadcast the 1936 Olympic Games in Berlin.

After Farnsworth returned to the US, he began experimental broadcasts, and invented a process for sterilising milk using radio waves, and a fog-penetrating beam for ships and airplanes. RCA, meanwhile, was perfecting its technology, including the invention of a “photomultiplier” tube that enhanced the Iconoscope’s signal, with an aim to launch electronic television at the 1939 World’s Fair in New York. Farnsworth had managed to outlast Sarnoff, and RCA was forced to pay US$1 million in royalties to settle the patent dispute in order to move ahead with their launch, where Sarnoff would effectively declare himself the father of television. When Farnsworth heard Sarnoff had taken the credit, he remarked to a reporter, “The baby has been born with a beard.” Sarnoff would ignore Farnsworth’s contribution, but at least Philo was set to reap the profits of his invention – or so he thought.

Unfortunately, World War II broke out soon after, and manufacturing facilities in the US were appropriated for the war effort. Television was put on hold, and Farnsworth’s patents would expire in the meantime. By the time post-war television started to gear up, Farnsworth was broke, and in 1951 he sold his company to International Telephone and Telegraph, where he worked on a number of inventions, including the forerunner to modern air-traffic control systems. Philo had done much for the invention of television, but saw little reward for it. RCA, on the other hand, moved its National Broadcasting Company into television with gusto, establishing a country-wide network of stations and a slate of television programming that would make it the number one broadcaster for decades.

Sarnoff had won.

…Or had he?

Without Philo T. Farnsworth to provoke him, Sarnoff may have not put as much (if any) effort into his pursuit of television. After all, he wasn’t so much interested in forging a brave new world as he was afraid of losing control over a new medium – or, in today’s lingo, he had FOMO. Farnsworth, meanwhile, may never have solved the problems with his image dissector, and without Sarnoff on his back, Zworykin may have never perfected the Iconoscope – Sanford Essig may have never over-baked his mica plate. Innovation needs competition, and so we declare this race a tie, for without all of the competitors, it is arguable the finish line might never have been crossed.

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