Receiving the ITA programmes 

17 July 2017 tbs.pm/12898

FREDERICK LIDSTONE brings you the facts in an authoritative statement

From the TV Mirror published 12 March 1955 by The Amalgamated Press

Millions of viewers are looking forward to the time when the ITA programmes will be available in their area, but are very puzzled by the conflicting ideas about the range of reception, and widely varying estimates of the money they will have to spend. There are hints of “difficulties,” “limited range,” “ghost images” and all  sorts of troubles.

I thought it was high time we had an authoritative statement on the matter, so that viewers all over the country could have a clear idea of where they stand, and I can give it to you, here and now.

The man who answered all my questions — and took great pains to do so — was Mr. N. Dundas Bryce, Executive Director of Belling and Lee Ltd. Considering that this firm has made practically half the television aerials in use in this country, there cannot be much they don’t know about TV reception; nor could you find anyone more concerned with the problems of receiving the ITA. And let it be said at once that there are problems.

Naturally enough, many people are mystified by this. They can go to their radio receiving set and tune in anything up to a dozen programmes with no trouble at all, even if the aerial is little more than a piece of wire trailing along the picture rail. Why all the fuss about TV? It had to have its own specially designed aerial to receive the BBC. Another aerial will have to be added to receive the ITA. Older sets will have to be fitted with an additional tuner. Even then there are stories of “difficulties.”

As to that, there always have been difficulties.

Consider, for a start, the difference between sending sounds and pictures through the air. Sound need not be perfect — indeed, under present circumstances with stations crowding in on one another, it never is. But the average human ear is not all that fussy. It can spend the whole evening listening to imperfect sound without worrying a great deal.

But pictures — ah, that’s different. The slightest blemish just cannot be missed; interference cannot be ignored. And the trouble is that the special wireless waves which bring you those pictures are the Teddy Boys of the radio world. They’re unpredictable, erratic, sometimes lawless.

It would be nice if one could take a map of Britain and a pencil compass, draw neat circles around each TV station and say: “Everyone within that circle will receive clear, steady pictures.”

The difficulty is that our geography isn’t made up in nice neat circles. Hills bob up all over the place, and man has made a few miniature ones of his own in the shape of gasholders, steel-framed buildings, and so on. They are all, in the radio sense, like the breakwaters you see on the beach, which play havoc with those powerful waves sweeping in.

Example: A man living in a valley only a few miles from a powerful BBC transmitter may find it difficult to get any picture at all, while one living fifty miles away can see perfectly, because there are no “breakwaters” in the way.

Large objects like gasholders can cause “ghost images” on the screen because part of the incoming wireless wave bounces off them and arrives at the set like an echo a split-second later.

Mr. Bryce told me that engineers installing aerials have even found cases where an aerial attached to one chimney on a roof gave no picture at all, while another only a few feet away brought perfect reception.

A note on inflation: The cumulative UK inflation rate since 1955 is  approximately 2520%. Figures shown in this article are the original prices, with, in [square brackets], that price converted to decimal money, times by 25.2 and then rounded for convenience.

Even the aerial rule “the higher the better” has its exceptions — though they are few. There is the story of the man living on a ground floor who bought an indoor aerial for his TV set and in order to find the ideal position, walked about with it while his wife watched the screen for best results.

Nowhere seemed very satisfactory until, out in the hall, he opened a door and fell down the cellar steps, still clutching the aerial. As he sat there rubbing his bruises his wife called out: “The picture’s perfect now.” The aerial was fixed … in the cellar.

We can complete our “Teddy Boy” analogy by saying that when one of these young malcontents is brought into Court the defence is: “He wanted to go straight, but came under influences which made him misbehave.” That’s true, too, of the TV wave. It wants to go straight, but there are all sorts of influences which prevent it from doing so.

So far we have been talking entirely of experiences gained in connection with the BBC transmissions sent out on a set of wavelengths known as Band I. The ITA transmissions are to use a set of waves called Band III — and it may be they will prove to be even more of a problem.

I can hear you saying: “Why ‘may be’ ? Don’t the experts know?”

Tests will start soon

The answer is that they don’t, for sure. Says Mr. Bryce: “Nowhere in the world is television being transmitted in exactly the same way as the ITA programmes will be, so it wasn’t possible for engineers to go abroad and study results. They have had to start from scratch. And the only test is to put a television picture on the air.

“That is why we have asked and obtained permission to erect, at once, a low-power vision transmitter on the actual site of the London ITA station. It will only send out a test pattern — similar to the BBC Test Card C — and transmission is scheduled to begin on April 1st.

“Then, over a wide area, reception tests will be carried out to see how the picture comes in. Within a week we shall have all the information we require.”

Top priority will be given to the question: “Are ghost images worse on Band III than on Band I?” There is a chance that on the ITA wavelength much smaller objects than gasholders might cause them.

Point No. 2 is that the rods of aerials for receiving the ITA are shorter than the BBC ones, and the amount of energy they pick up and pass to the set will be smaller. This means that with some receivers it may be difficult to make up the difference at ITA wavelengths, and only a more sensitive aerial can help. That is why so many Band III aerials will have a lot of rods, or elements.

Well, the whole television story is one of triumph over difficulty, and, says Mr. Bryce, speaking for the roof-top men: “We believe that we have the answers to even the most intricate problems.”

Now let us talk about you as a potential viewer of ITA programmes and give you some idea what it is likely to cost.

Obviously if your set is one of the “single programme’’ type you will have to have it fitted with a converter so that you can switch from one programme to another. This will cost you an average of £6 [£151].

On the question of the second aerial needed for ITA it is easy to visualise the Suspicious Viewer, looking a little like one of Al Read’s characters, saying “‘Ave yer done? Think I’m made o’ money? Why should I need another aerial? Go on, tell me. TELL ME !’”

The trouble is that it is difficult to do so without indulging in technicalities. I asked Mr. Bryce how he thought it could best be explained. He put it this way: Imagine that you have two pianos in the same room. Strike a note — say middle C — on one and immediately the middle C string on the other piano vibrates in sympathy and gives out the same note. Strike a higher note and the same thing happens to the appropriate — and shorter — wire on the second piano.

Regard the two notes struck as being transmissions from the BBC and the IT A, and the two wires in the other piano as the aerials on your roof, and you get something of the idea. The rods of the ITA aerial will, as has been said, be shorter than the BBC one.

Question: Can the second aerial be attached to your present one ?

Answer: It all depends. Your present aerial points in the direction of the BBC station from which you take your picture. If — as may happen — your ITA station will be on the same site as the BBC one or near, then your aerial can be adapted to take both sets of rods. The same applies if a line drawn between your house, the ITA and the BBC is a fairly straight one.


 

But if the two stations are in entirely different directions, then there is nothing for it but two separate aerials, correctly pointed, or “orientated.”

Adapters, so far as this firm is concerned, will cost between 4s. 6d. [£5.70] and 36s. [£45] according to your distance from the station and the aerial you have in use at the moment.

Entirely separate aerials start at 31s. [£39] and there is an attic one suitable for use within about seven miles of the transmitter. There is a whole range of outdoor aerials for use according to circumstances, and prices here start at £2 11s. [£64]. An average would probably be about four guineas [£106], but for fringe area reception it may go to £7 10s. [£190] or more. Add to these prices a charge for installation, which will be in the region of £2 [£50] to £3 [£76].

For all viewers who will need separate aerials — and for some whose BBC aerial can also take the ITA one — another gadget is necessary. This is a little box affair called a diplexer, and costs 12s. 6d. [£16]. In simple terms it helps the receiver to cope with the programmes coming in at the same time from both aerials.

So as soon as you know where your ITA station will be situated you can do a little arithmetic, with the help of your dealer, and budget for the new programmes.

Final word from Mr. Bryce is this: If you want to receive the ITA programmes as soon as they come to your area, get busy as quickly as you can. Your set will have to be taken away to have the converter fitted, and as for putting up the aerial, do it early and avoid the rush.

In some areas — London, for example — viewers will be able to get the job done during the summer months. Within a short while now it will be known which of the ITA transmissions will be coming from the same direction as those from the BBC, so other areas will be able to get busy.

Regard the question of aerial erection as an expert job, which it is, and see that you get the best man available to do it.

Test card C from Moel-y-Parc in the 1960s

 

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