AP mast (2K)


by Arthur Dungate


Demfilm: The development of television



In 1952-53 part of the Demfilm contained a reel depicting the development of television tranmitters. Here is the text of Reel 15 of the Demfilm Edition 102-3.

It is introduced by Sylvia Peters -


Sylvia Peters (4K)

Since the end of the War, the BBC has built new television transmitters to bring the main centres of population, in England, Scotland and Wales, into the television service area. At the same time new studios are being built in London, and in the film that follows we give a brief report on this work".


Naration by Macdonald Hobley -

Every age has left its landmarks on the country - the stone monolith, the cathedral spire, the Martello tower, the Victorian railway station, the television mast. In 1949 this mast was built in the Midlands, rising 750 feet above the first regional television tranmitter at Sutton Coldfield. Within two years a similar mast had been built on the Pennine ridge at Holme Moss, and from the second regional transmitter our programmes went out to the people of the north of England.

Soon afterwards the signals were passed on to Scotland by a series of linking radio stations set on the hills of Yorkshire, Durham and the border. And at Kirk o'Shotts, beside the road between Edinburgh and Glasgow, a third identical mast was built to serve the lowlands.

While this was being drawn, like a straight pencil-mark up the sky, work was already beginning on a fourth copy, and by the time you could look down on the completed station at Kirk o'Shotts, a fourth regional transmitter was being prepared at Wenvoe in south Wales, fed by a cable link from London.



At intervals along the route have been built repeater stations to boost the signal and pass it on. Through Newbury and down the Great West Road to Bristol.

From Bristol the cable runs on, under the Severn estuary into Wales.

A chain of repeater stations lies across the green landscape of Monmouthshire, tracing the cable route to Newport, and on into Glamorgan.

At Cardiff the cable is fed into the telphone repeater station, for the whole link is a GPO line installed and maintained by Post Office engineers. From here it continues westward, past the industrial suburbs, the modern civic center and the ancient castle, until, beyond the houses on the road to Barry, it reaches the Wenvoe station.

Here it ends in the BBC transmitter building. The signals it has carried from London are fed into the main transmitter and then passed as high frequency waves to the mast and up to the aerials, to radiate across south Wales and western England.

The equipment here is similar to that of the other stations, high power sound and vision transmitters in the main hall, and an alternative medium power transmitter in a separate building. Each transmitter has a control room where the engineer in charge regulates the signals passing up to the aerials and so out to the homes of viewers on both sides of the Bristol Channel.




Naration by Macdonald Hobley:

Have you ever thought what would happen if your set showed you pictures of the road outside your home? You would see some of the passing vehicles clearly enough - a Post Office van, or a service vehicle, or a railway lorry. Or the car of some thoughtful private motorist, for interference supressors have been fitted to all their engines.

But you wouldn't be able to see this car properly, because it spoils your picture as it passes, and not only your picture. As this man drives along he leaves a trail of interference at least as bad as this on all the television screens on his route.

Yet a few minutes at a garage or a radio dealers will stop this nuisance for good.



Shop assistant:   Morning Sir, can I help you?
Customer:   I want a suppressor for my car.
Assistant:   What type of distributor has your car got sir?
Customer:   I'm not sure.
Assistant:   Well if it's this type, you need this suppressor, you just fit it into the distributor head like this, and you fit the end of the main high tension lead in like that.
Customer:   I don't think my distributor's like that one, it's like the other one.
Assistant:   Oh well, in that case you want this other sort of suppressor.That fits into the high tension lead itself. I'll have it fixed for you if you'd like to wait a moment, it won't take very long.
Customer:   Thankyou, it's just outside.
Assistant picks up internal phone:   Er Mr Lloyd, could you bring through a cut-lead suppressor please and fit it to a customer's car? Thankyou.
Assistant [to customer]:   Thankyou. Thankyou very much sir, the electrician will be coming through that way.
Customer:   Thankyou, good day.



One of these suppressors should be fitted to the main ignition lead as near to the distributor as possible, and if you're in any doubt, an attendant will fit it for you. On some engines suppressors have to be fitted to the plug leads. But for most cars a simple suppressor like this one, or the screw-in type, will do the job. It can be done from about two or three shillings, and it's permanent.

If every motorist did this, literally millions of television viewers would get better reception. suppressors lengthen the life of the plugs, without detracting from the engine performance, and even helps starting in very cold weather. All new cars are now fitted with suppressors at the factory, for ignition suppression is highly important in a country widely served by television.

But what about your car? Does it mark your thoughtless progress across the screens of your neighbours' sets?

[irate viewer hurls something at his tv screen, and the old car outside blows up....]