100 Voices that made the BBC – The Birth of TV

[Mike Watterson]

Lots of people here know this, but some might not, also most visitors will not.

BBC Says:

But the problem remained of how to break an original image into small sections so that they could be transmitted separately, though simultaneously, before being ‘reassembled’ at a distant receiver. And it was in Britain that a ‘mechanical’ approach to this problem was pursued with the most striking results. In 1924, a young Scottish engineer, John Logie Baird, developed a way of passing a beam of light through a rapidly spinning disc punched with holes, so that a simple image could be ‘scanned’, transmitted, and reconverted

It's nonsense!
It was also being done in USA.

He initially was only copying Victorian era Nipcow
https://en.wikipedia.org/wiki/Paul_Gottlieb_Nipkow
https://en.wikipedia.org/wiki/Nipkow_disk
https://en.wikipedia.org/wiki/Mechanical_television

Mechanical TV was a curiosity that could use AM transmitters after hours. Kits were sold in USA also. It wasn't a Baird invention.

Electronic Television

In 1907, Russian scientist Boris Rosing used a CRT in the receiving end of an experimental video signal to form a picture. He managed to display simple geometric shapes onto the screen, which marked the first time that CRT technology was used for what is now known as television.[20]In 1897, J. J. Thomson, an English physicist, in his three famous experiments was able to deflect cathode rays, a fundamental function of the modern Cathode Ray Tube (CRT). The earliest version of the CRT was invented by the German physicist Karl Ferdinand Braun in 1897 and is also known as the Braun tube.] It was a cold-cathode diode, a modification of the Crookes tube with a phosphor-coated screen.A cathode ray tube was successfully demonstrated as a displaying device by the German Professor Max Dieckmann in 1906, his experimental results were published by the journal Scientific American in 1909.[23] In 1908 Alan Archibald Campbell-Swinton, fellow of the Royal Society (UK), published a letter in the scientific journal Nature in which he described how "distant electric vision" could be achieved by using a cathode ray tube (or "Braun" tube) as both a transmitting and receiving device He expanded on his vision in a speech given in London in 1911 and reported in The Times[26] and the Journal of the Röntgen Society. In a letter to Nature published in October 1926, Campbell-Swinton also announced the results of some "not very successful experiments" he had conducted with G. M. Minchin and J. C. M. Stanton. They had attempted to generate an electrical signal by projecting an image onto a selenium-coated metal plate that was simultaneously scanned by a cathode ray beam. These experiments were conducted before March 1914, when Minchin died.[31] They were later repeated in 1937 by two different teams, H. Miller and J. W. Strange from EMI,[32] and H. Iams and A. Rose from RCA Both teams succeeded in transmitting "very faint" images with the original Campbell-Swinton's selenium-coated plate. Although others had experimented with using a cathode ray tube as a receiver, the concept of using one as a transmitter was novel. The first cathode ray tube to use a hot cathode was developed by John B. Johnson (who gave his name to the term Johnson noise) and Harry Weiner Weinhart of Western Electric, and became a commercial product in 1922.

https://en.wikipedia.org/wiki/History_of...television
Dutch Experimenters used Nipkow disk cameras with CRT displays when Baird was messing with disk and mirror displays.

Rosing had filed his first patent on a television system in 1907, featuring a very early cathode ray tube as a receiver, and a mechanical device as a transmitter. Its demonstration in 1911, based on an improved design, was the first world's demonstration of TV of any kind.

In 1926, Hungarian engineer Kálmán Tihanyi designed a television system utilizing fully electronic scanning and display elements and employing the principle of "charge storage" within the scanning (or "camera") tube

On December 25, 1926, Kenjiro Takayanagi demonstrated a TV system with a 40-line resolution that employed a CRT display at Hamamatsu Industrial High School in Japan.

Why didn't Baird use a CRT from the very start for the receiver? Cost cutting? Ignorance?

The USPTO was broken in 19th C, with Edison pursuing Film makers, for patents he should never have had (later invalidated). USPTO is STILL broken.
Armstrong & RCA should not have had patents for Superhet and FM, which are based on mathematics.

Vladimir Zworykin was also experimenting with the cathode ray tube to create and show images. While working for Westinghouse Electric in 1923, he began to develop an electronic camera tube. But in a 1925 demonstration, the image was dim, had low contrast and poor definition, and was stationary. Zworykin's imaging tube never got beyond the laboratory stage. But RCA, which acquired the Westinghouse patent, asserted that the patent for Farnsworth's 1927 image dissector was written so broadly that it would exclude any other electronic imaging device. Thus RCA, on the basis of Zworykin's 1923 patent application, filed a patent interference suit against Farnsworth. The U.S. Patent Office examiner disagreed in a 1935 decision, finding priority of invention for Farnsworth against Zworykin. Farnsworth claimed that Zworykin's 1923 system would be unable to produce an electrical image of the type to challenge his patent. Zworykin received a patent in 1928 for a color transmission version of his 1923 patent application,[48] he also divided his original application in 1931.[49] Zworykin was unable or unwilling to introduce evidence of a working model of his tube that was based on his 1923 patent application. In September 1939, after losing an appeal in the courts and determined to go forward with the commercial manufacturing of television equipment, RCA agreed to pay Farnsworth US$1 million over a ten-year period, in addition to license payments, to use Farnsworth's patents.[50][51]

In 1933 RCA introduced an improved camera tube that relied on Tihanyi's charge storage principle

https://en.wikipedia.org/wiki/History_of...television


https://en.wikipedia.org/wiki/Vladimir_K._Zworykin

Vladimir Kosmich Zworykin (Russian: Влади́мир Козьми́ч Зворы́кин, Vladimir Koz'mich Zvorykin; July 29 [O.S. July 17] 1888 – July 29, 1982) was a Russian inventor, engineer, and pioneer of television technology. Educated in Russia and in France, he spent most of his life in the United States. Zworykin invented a television transmitting and receiving system employing cathode ray tubes. He played a role in the practical development of television from the early thirties, including charge storage-type tubes, infrared image tubes and the electron microscope

Fax is the precursor to TV and was also transmitted on MW AM after radio programs as alternative to Nipkow / Baird systems in USA in early 1930s. It was used commercially on wires from 1856.

Facsimile transmission systems for still photographs pioneered methods of mechanical scanning of images in early 19th century. Alexander Bain introduced the facsimile machine in 1843 to 1846. Frederick Bakewell demonstrated a working laboratory version in 1851. The first practical facsimile system, working on telegraph lines, was developed and put into service by Giovanni Caselli from 1856 onward.

So how important is Baird?