Secret behind the ancient black & white Tv with magnetic ray tube that $1000s of dollars

THE BEGINNING OF THE END OF BLACK AND WHITE TV
It was not until 1954 that colour broadcasting officially began anywhere. This happened in the USA, but it was not without its troubles.

A field-sequential colour system, based on a rotating colour filter wheel, had been unceremoniously shut down by the FCC in 1951, with the American television giants CBS and RCA proceeding to battle it out for control of colour.




The second generation American colour TV set, which became available in 1954, was an RCA set with a CBS picture tube. By the late 1950s, colour TV had become established in several major US cities. However, the early American colour TV sets were extremely expensive, and required a lot of adjustment and maintenance.

Meanwhile in Britain, due to a combination of cost, caution, and lack of a clear way forward technologically, colour broadcasting would take a few more years to arrive.

In 1967, it was our own BBC who pioneered the first colour broadcasting anywhere in Europe. However, the standard selected, PAL, which stands for Phase Alternating Line, was in fact a German improvement of the mid-50s American colour system. PAL was developed at Telefunken under Walter Bruch between 1962 and 1965.

Colour broadcasts began on BBC2 in 1967, arriving on ITV and BBC1 in 1969. To support the costs, colour TV licences were introduced on 1st January 1968, costing £10—twice the price of the standard £5 black and white TV license. Today, the colour license costs £145.50—three times the price of the black and white license at £49.

BBC2 originally launched in black and white on 20th April 1964, but intrinsic in its higher bandwidth television signal (Ultra High Frequency, as opposed to BBC1’s Very High Frequency) was the ability to transmit 625 lines in black and white, and eventually, PAL colour.

THE BLACK AND WHITE TELEVISION IMAGE
Cinema retained the monopoly on colour moving images during television’s first three decades. This helped to keep audiences going to films but it also whetted the public appetite for colour on television.

However, the film industry’s monopoly of colour did not help it to survive the arrival of television unscathed. Television led to the closure of many cinemas in the 1950s, as well as having similarly negative impacts on national magazines, pubs and night clubs.

The television image was lower in resolution in those days, with the BBC1 image comprising 405 horizontal lines. As I’ve already mentioned, 625 line images arrived with BBC2 in 1964, but surprisingly little was made of the fact that this meant sharper and more watchable black and white images.

A television screen showing The Duchess of Malfi, 4 November 1949, A Tanner © Daily Herald / National Media Museum, Bradford / SSPL
A photograph of a 405 line television screen showing a production of John Webster’s play The Duchess of Malfi, 4 November 1949, A. Tanner © Science Museum Group collection

Until about 1960 the only way in which a complete programme could be recorded was on cine film, and this was rarely done because of the cost.

1964 was the same year in which Marshall McLuhan published his best-known book, Understanding Media. In the years leading up to 1964 most viewers’ experience of television, like that of McLuhan, had been via small sets which also had an image that was rather small, an image that would be called ‘blurry’ by today’s standards.

McLuhan observed how television programmes in those days called for special production techniques in terms of both image and sound.

The TV producer will point out that speech on television must not have the careful precision necessary in the theater. The TV actor does not have to project either his voice or himself. Likewise, TV acting is so extremely intimate, because of the peculiar involvement of the viewer with the completion or ‘closing’ of the TV image, that the actor must achieve a great degree of spontaneous casualness that would be irrelevant in movie and lost on stage. For the audience participates in the inner life of the TV actor as fully as in the outer life of the movie star. Technically, TV tends to be a close-up medium. The close-up that in the movie is used for shock is, on TV, a quite casual thing. And whereas a glossy photo the size of the TV screen would show a dozen faces in adequate detail, a dozen faces on the TV screen are only a blur.
Televised production of Magyar Melody at His Majesty's Theatre, 27 March 1939 © Daily Herald / National Media Museum, Bradford / SSPL. Creative Commons BY-NC-SAMagyar Melody was the first musical to be broadcast directly from a theatre and shown on television. Captions on screen introduced the television audience to the actors and actresses.
Televised production of Magyar Melody at His Majesty’s Theatre, 27 March 1939 © Science Museum Group collection

Magyar Melody was the first musical to be broadcast directly from a theatre and shown on television. Captions on screen introduced the television audience to the actors and actresses.

COLOUR COMES TO BRITAIN
In July 1967, the BBC led the way in broadcasting the first regular colour television service in Europe. The first programme was an outside broadcast of the Wimbledon Tennis Championships.

By mid-1968 almost every BBC2 programme was in colour. Six months later, colour came to BBC1.

The impact of the arrival of colour in 1967 cannot easily be isolated from that of the improved 625 line resolution of 1964. Colour and image quality cannot be made exclusive from one another having been introduced at essentially the same time, plus their effects on the viewer are already similar.

Improved picture detail and colour both mean more realism in images, and improved images mean less interpretation and involvement—less guesswork required for the viewer.

Technically, with the arrival of bigger and better colour sets, television could—very gradually—become less of the close-up medium as described by McLuhan, with screen sizes increasing, more detail in images, and less burden on the viewer to ‘fill in’ the missing colour information.

Colour made television more valuable as a medium, as the license fee would indicate. Involvement ‘work’ in decoding the image was exchanged for more desirable experience ‘play’ of the programmes themselves.

This evolution of television technology epitomises the goal of television engineers—to create a more effective illusion of reality. Similarly, an improved television image is desirable to both the TV producer and the TV viewer.

WHY KEEP A BLACK AND WHITE SET?
Perhaps the most interesting application in which a black and white television display makes sense today is for the viewing of black and white films, because colour displays can only approximate black and white images, as they do all colours, by blending red, blue and green, using the additive colour principle.

In mixing colours to produce black and white, colour displays are simply not as efficient as the old black and white sets purpose-built for showing black and white images.

The old black and white picture tube TVs have a phosphorescent coating distributed uniformly behind the glass screen. When this coating is struck by the rapidly moving electron beam (raster) generated by the electron gun at the rear of the picture tube, the screen illuminates accordingly.

Monochrome television receiver, c. 1951, His Master's Voice (HMV) © National Media Museum, Bradford / SSPL. Creative Commons BY-NC-SA
Monochrome television receiver, c. 1951, His Master’s Voice (HMV) © Science Museum Group collection

The beautifully simple way this works also means that the screen on a black and white set requires no metal grid to align sets of colour pixels (this grid is known as a shadow mask). With no shadow mask, black and white sets have no ‘screen door’ effect. In other words, the area of the screen that actually lights up, known as ‘the pixel fill rate’, is 100%. Today, our modern colour sets cannot achieve a 100% pixel fill rate, although some organic (OLED) display sets come close.

Therefore, if you are a serious black and white film and TV enthusiast, and are relatively uninterested in modern programmes, an old black and white set may be just the thing for you.

The following recording was made in the Lime Grove Studios in London on 3 January 1985. It depicts the final moments of 405 line transmission from the BBC Crystal Palace transmitter. The TV receiver is a model T-18 Baird set manufactured in 1938. The set is actually working and picking up the transmission via a VHF roof top antenna at the studio.


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