1951

April sees a suprise purchase tax increase whereby it doubled 66.7%. The excuse given by Hugh Gaitskell was that he wished to relieve the pressure on home demand, thus making easier the smooth transition to defence ; er, what ?Not suprisingly there was an outcry from the industry that had already considered 33.3% somewhat of a burden. This increase was the final nail in the coffin for Hale Electric, who used the trade name 'Etronic', as having just invested large amounts in components they found they could no longer cost effectively manufacture sets and they folded less than 12 months later.

Also in April the Postmaster General announced in the House of Commons that in view of the then current defence programme it had been decided to postpone indefinately the building of the five low-power stations at Southampton, Plymouth, Newcastle, Aberdeen and Belfast. The three high power transmitters yet to be built at Holme Moss, Kirk 'o Shotts and Wenvoe would however be completed as planned.

An extra hours worth of TV trade test transmissions begin in June, broadcast between 4 and 5pM.

The 1951 election saw the first party political broadcasts in the UK. On each one of three consecutive nights one of the three major political partys were allowed a 15 minute slot. Since, in 1951, there was only one television channel you couldn't just switch channels when these broadcasts started !

Transmitters

"Keenly interested, Miss Gracie Fields discusses the merits of Philips Projection TV Receiver, 1800A, with Mr. N. C. Pratt, Publicity Manager". Yeah, right!		Typical southerner's view of the cold north.!

In July the first low power signals radiated from Holme Moss. The first main aerial tests begin the following month, arranged so as to co-incide with the announcement that the station would be officially opened on the 12th October. With it came the potential of an additional 5 million viewers, an opertunity television manufacturers were keen to cash in on. Philips employed the northern lass herself, Gracie Fields, to promote their range of televisions for the north.

Exhibitions

National Radio Show

		At £757, this Decca set was the most expensive television of the show - wonder if they ever managed to sell one !?

This year sees the show change venue from Olympia to Earls Court.

With the imminent opening of the Holme Moss transmitter it should be no suprise that the main attraction at the show was Television. Few if any manufacturers showed models with screen sizes less than 12-inch, with many showing 15- and 16-inch models and one, H.M.V., even showing a 21" screen..

Of the 35 television manufacturers at the event nine showed projection models, including Decca who presented the most expensive television of the show.

One new name at the show was Stella, a trade name that had been introduced by Philips a few months previously.

Fesitval Of Britain

The Festival of Britain opened in May. In true British tradition, the galleries concerned with radio, television and electronics were only partially completed when the festival opened. In fact they still weren't completed in September when the Festival closed !

Technical

C.R.T.s

HMV introduce a television with an enormous 21" screen. The C.R.T. was a round metal-tube. The set, the model 1820 pictured opposite, also came with an equally enormous remote control (lower center of picture).

In around June GEC release two 12-inch CRT's, the 6705A (6.3v heater) and 6706A (10.8v heater). These were auminised and had fairly flat face plates.

Meanwhile in America a range of CRT's are introduced that were focussed electrostatically instead of the usual method of using permanent or electro- magnets. The driving force behind the development was not one of technical improvement, rather it was as part of an effort to conserve copper and cobalt for the American defence program. It was claimed that a typcial elecromagnet required around 2Lb of copper and a similar amount of magnet steel (which would contain cobalt). However the obvious financial savings from such material were counterbalanced by the significantly greater accuracy of construction required for the electron gun structure and hence it would be some years before the technique would see widespread use in Britain.

Valves

In around May or June Brimar introduced the 6CD6G line output vlve and 6U4GT efficiency ('boost') diode.

More Lines ?

The main objection to high definition TV services is the bandwidth that such services required. This was a particular problem in France with their 819-line system requireing a staggering 14MHz channel bandwidth (even today transmissions are of only 5MHz bandwidth). In light of this, Radiodiffusion Francaise began test transmission using a 4MHz bandwith 819 line system, the perhaps dubious theory being that good line definition was more important to the viewer than horizontal definition. To illustrate this, consider the following :-

In terms of bandwidth, 819 lines interlaced (i.e. 25Hz) is quivalent to ~405 lines non-interlaces (i.e. 50Hz).

For a picture that had the usual 4:3 aspect ratio, you would be looking at a (5/4)*405 i.e. resolve 505 dots horizontally.

One line of a 819-line signal has a 50uS duration. So to have ~500 dots on that line requires 50uS / 500dots i.e. 0.1uS per dot i.e. 10MHz, way above Radiodiffusion Francaise's 4MHz test.

Companies

English Electric

Although FM broadcasts were as ye years away, the BBC had already performed several trials and the subject often appeared in many electrical-orientated magazines. English Electric decided to try and steal a march by introducing an "F.M. Facility" in their top of the range combined TV/radio console model 1651. It is not clear what form the "F.M. facility" took but since the radio would not have been equipped for Band II reception on which FM filnally appeared the facility was probably never to be used.

Others

• Scophony Ltd is sold to EMI Engineering Development Ltd.
  
• In September Ekco celebrated their silver jubillee.
  

News From Abroad

France

10-inch 819-line model by Radio-Industrie			12-inch model by Ducretet-Thomson, available for 441 or 819 lines

France's first TV exhibition, "Salon de la Télévision", opened on the 28th September, running until October 10th. The exhibition featured eighteen television manufacturers and proved so successful that at the weekends the organisers, Télévision Française, had to limit the number of admissions.

Of the 81 televisions exhibited, 57 were for new 819-line transmissions (that had only begun in May), 18 for 441-line transmissions with the remaining 6 being dual standard. Around half of the televisions had 12-inch C.R.T.s with another 10% being 14-inch. The remainder covered the range 6- to 24-inch, much wider than in England. However unlike England there were very few projection models shown.

In England there was constant talk of whether or not the 405-line system should be ditched in favour of a higher definition. One reason for not doing so was that, it was claimed, was that receivers would be more expensive. This view can be supported by looking at the cheapest set at the French Show, a 6-inch model by Sonara housed in a cast aluminium cabinet. It was available as a 441-line version cost the equivalent of ~£54 whereas the 819-line version cost the equivalent of ~£70.

Elsewhere

In America towards the start of the year, RCA introduce a rectangular metal C.R.T. with a picture area of ~14.5-by-11 inches, equivalent to an 18-inch round C.R.T.

In Denmark, experimental television broadcasts had ceased. The Danish State Broadcasting argued that the resumption of TV transmissions was imperativebecause it would enable the industry to work up a substantial export trade, estimated at 5-million kroner (then ~£250,000). On the strength of this, the Danish Government authorised transmissions of 1 hour three times a week, not exactly generous given the 50kr (~£2½) TV license fee ! The transmissions began on October 1st. To ensure manufacturers concentrated on export trade they were only allowed to produce a total of 1,500 sets for the home market. These sets were not cheap, the cheapest costing around 2,000kr (~£100) plus taxes.

Whilst television broadcats in New Zealand were still years away, S.O.S. Radio of Queens Street, Auckland imported a Masteradio television which they had purchased from Altham Radio Co. of Manchester. It was displayed in S.O.S. Radio's shop window, displaying a simple pattern generated by a Taylor signal generator. Even this simple demonstration generated considerable interest in the public.

On September 3rd regular television broadcasts begin in Western Germany from its first transmitter. The station was installed in one of the wartime aircraft (flack) towers in the center of Hamuburg and used the 625-line system. The 1kW vision transmitter operated on 189.25MHz eith the 0.3kW sound transmitter operating on 195.75MHz.

On October 2nd Holland began regular television transmissions from studios at Bussom, albeit only four one-hour programmes a week. Although 2/3rds of the country's population were in range of the transmitter apparently only a few hundred people had televisions sets, despite there having been experimental broadcasts since March 1948.

In September television test transmissions begin on Channel 7 in Argentina with a public service following in November.