1954

Technical

C.R.T.s.

With Cathodean having introduced a monster 27-inch CRT the previous year, pictures could be produced that rivalled the size of pictures normally requiring the use of projection systems, at least as far as sets intended for domestic use were concerned. This year Brimar followed suit with a similarly sized CRT, the C21HM.

EMI 3/17 C.R.T.

In response to this, EMI introduced a new CRT for projection sets, enabling the size of projection pictures to be increased still further. The size of the projected image was ultimately limited by picture brightness, larger pictures requiring more light generation. Until now, the 2½-inch Mullard MW6/2, operating at a high EHT of 25KV, had been used in every domestic projection set since the start of the fifties. The new EMI CRT, type 3/17, had an increased diameter of 3¾-inch giving over twice the screen area of the MW6/2 and operated at an even higher E.H.T. of 28KV. Also, whereas the MW6/2 had a relatively flat face, the 3/17 was more curved which, it was claimed, reduced the defocussing at the edges of the screen that tended to occur with the MW6/2. However the writing was on the wall for projection sets and it seems the only set to utilise this CRT was an HMV model.

Nera C48 forward projection set with 4ft x 3ft screen.

Just as HMV had finally got around to making their first projection set the demand for domestic projection sets fell as larger "normal" CRT's became available.

There was still demand for very large screen projection sets for use in clubs, hospitals and such like. One firm, "Nera", specialised in this type of equipment and produced the first self-contained projection set capable of generating a 4ft-by-3ft picture which would normally require a seperate projector unit with a remote screen.

With the introduction of 90-degree C.R.T.s which required 50% more scanning power than the previous 70-degree types, Mullard presented a design for a high efficiency timebase. The key improvement was to "tune" the leakage inductance of the line output transformer which had the effect of both reducing the line output and efficiency diode's flyback voltage by around 20% whilst increasing the E.H.T. voltage.

Valves

With the impending arrival of transmissions in Band III at frequencies some 3-4 times higher than the current Band I, Mullard introduced two new valves for use in the tuner of a TV. The first was the PCC84, a double triode intended to be connected in a cascode arrangement to act as a front end amplifier. The second was the PCF80, a triode-pentode for use in the frequency changer, the triode intended for operation in a Colpitts oscillator with the pentode acting as a mixer. In time, the PCF80 could be found in quite unrelated circuitry with various degrees of success such as in the disasterous 1955 Pye V14C.

Transmitters

On the 13th November the first of the B.B.C.'s planned medium power tranmitters opens at Rowridge on the Isle of Wight. Transmitting on channel 3, it replaced the temporary station at Truleigh Hill near Brighton that had opened in the previous year.

In September regular state-run television starts in Sweden. It had been a long battle, starting in 1947 when a joint committee was set up to study television research. They decided to build an experimental transmitter transmitter in Stockholm.

All was quiet until 1950 when the Swedish Board of Telegraphs and the Swedish State Broadcasting Company asked the Government for a grant for the purchase of experimental equipment. The Government say "No". Instead, the following year, a Government commission was set up to inquire into television.

In 1952 the commission asked the Government for funds to start some television activities in 1954. The Government said "No".

In 1953 a large group consisting of four large firms manufacturing radio and TV equipment, various co-operatives, the Association of Retailers and the Agricultural Federation (!?) asked the Government for permission to start a commercial TV service. Well, by now you can guess what the Government said.

Then in 1954, presumably in a moment of weakness, a Swedish film producer was granted permission to stage a purely commercial television week. The intention was to show that commercial TV could have educational and cultural value. But when the film producer asked to continue experiments between 1st September 1954 and 30th May 1955 the Government were back to normal and said "No".

But on the 29th October 1954 experimental 625-line broadcasts were started by the State Radio from a 5kW station operating from the Technical High School in Stockholm. Initially consisting of just one or two hours of broadcasts per week, this "experiment" continued for several years with a slow increase in the amount of programming.

Inside a French television utilising a printed circuit.

The French radio manufacturer J. Visseaux S.A. manufacture a television utilising printed circuits. It would be another two or three years before UK televisions made use of this technology. However the most unusual feature of the French design was the creation of the various tuning coils and capacitors using tracks on the PCB itself ; only low value components could be implemented this way, which was fine for the high frequencies used in television but were not suitable for broadcast radio use. Whilst the valves themselves were mounted via holders directly onto the PCB, heavier components such as electolytic capacitors and power transformers were still mounted on a seperate metal frame.

As of June there were three low power tranmitters in operation, received on 125,000 receivers. The television license fee was 4,350fr (~£4 9s). The fourth tranmitter opened at Marseilles in September and was closely followed by another transmitter at Lyon-Ville on the 15th October.

French 819-line test card. Link to larger view [89K]		An example of a typically ornate French receiver (manufactured by Gétou).

Elsewhere

The year starts with regular television test transmissions from Tryvannshøgda transmitter in Norway from the 1st January.

Canada sees rapid expansion of it's television services. The addition of 19 new transmitters, making 24 in total, the proportion of homes with television doubleds to 22%, with the 23 Canadian manufacturers producing 612,000 sets between them.

In October the U.S. Military Transport Service opens their first television station. Operating in the Azores, it transmitted telefilms to American troops and their families.

Later in the year it was estimated that in Budapest, Hungary, there were around 200 foreign made sets in use, presumably picking up transmissions from neighbouring countries. These owners were invited to criticise experimental transmissions of films by the engineers involved in planning Hungary's first TV station due to open the following year.

In Russia, by the end of the year it was estimated that some 70,000 televisions were in operation in Moscow where the total population was around eight million. Purchasers of such sets had a wide choice ... of two sets ! One had a 6x5inch screen whilst the second model was a larger screen version with a 7x5inch picture.

Television services start in Colombia, Czechoslovakia, Finland, Monaco (November) and Poland (June).

Daft Idea of the Year.

 

Words fail me !!!		But new it wasn't, as shown in this photo from mid-1935.